title: Nakam

text: About 30 former Nakam operatives boarded the ship "Biriya" on 23 June 1946 and arrived by the end of July following brief detention by the British authorities. They received a warm welcome at Kovner's kibbutz, Ein HaHoresh, from leading members of the Haganah and the Israeli Labor Party, and were invited to travel through the country. Although Kovner, and the majority of the operatives, considered that the time for revenge had passed, a small group led by Bolek Ben-Ya'akov returned to Europe to continue the mission. Nine other Nakam operatives broke away in the spring of 1947 and returned to Europe the following year, helped by Labor Party politician Abba Hushi.


title: Nakam

text: The breakaway groups faced mounting challenges, both logistical and financial, and the foundation of the Federal Republic of Germany in 1949 made illegal operations even more difficult. Many of the members turned to a life of crime to support themselves, and then tried to escape from German jails with the help of former French Resistance members. Most returned to Israel between 1950 and 1952. Ben-Ya'akov said in an interview that he "could not have looked at himself in the mirror" if he had not tried to get revenge, and that he still deeply regretted that it did not succeed. After coming to Israel, former Nakam members refused to speak about their experiences for several decades, only beginning to discuss the issue in the 1980s. Porat writes that Kovner "committed political suicide" by participating in Nakam; she describes its failure as a "miracle". Members of the group showed no remorse, said that the Germans "deserved it", and wanted recognition, rather than forgiveness, for their actions.


title: Nakam

text: In 1999, Harmatz and Distel appeared in a documentary and discussed their role in Nakam. Distel maintained that Nakam's actions were moral and that the Jews "had a right to revenge against the Germans". German prosecutors opened an investigation against them for attempted murder, but halted the preliminary investigation in 2000 because of the "unusual circumstances". , four members of the group are reported to be still alive.


title: Nakam

text: An early journalistic account of Nakam's mission is in Michael Bar-Zohar's 1969 book "The Avengers". The story was given a fictionalized treatment in "Forged in Fire" by Michael Elkins in 1971. Jonathan Freedland's novel "The Final Reckoning" is based on the story. The story of Nakam has also entered German popular culture. In 2009, Daniel Kahn & the Painted Bird, a Germany-based klezmer band, recorded a song called "Six Million Germans (Nakam)". Based on tapes Kovner made on his deathbed describing his activities in Nakam, a television documentary was produced by Channel 4 for its "Secret History" series titled "Holocaust – The Revenge Plot", which was first broadcast on Holocaust Memorial Day, 27 January 2018.


title: Nakam

text: According to Israeli terrorism experts Ehud Sprinzak and Idith Zertal, Nakam's worldview was similar to messianic groups or cults because of its belief that the world was so evil as to deserve large-scale catastrophe. Unlike most terrorist organizations which commit violence for political reasons and hope for a new, better future through terror, Nakam wanted to kill indiscriminately. The Nakam operatives came from "heavily brutalized communities" which, according to Sprinzak and Zertal, sometimes consider catastrophic violence.


title: Nakam

text: Dina Porat is the first academic historian to systematically study the group, meeting with many of the survivors and gaining access to their private documents. She hypothesizes that the failure of the attack may have been deliberate, as Kovner and other leaders began to realize that it could have greatly harmed the Jewish people. She struggled to reconcile the personalities of Nakam's members with the actions that they tried to carry out. When asked how he could plan an attack in which many innocent people would have been killed, one survivor explained that "[i]f you had been there with me, at the end of the war, you wouldn't talk that way". Porat's 2019 book on Nakam is titled "Vengeance and Retribution Are Mine" (), a phrase from the Psalms which expresses her belief that the Jewish people are best to leave vengeance in the hands of the God of Israel.


title: Nakam

text: In 2021, the movie "Plan A", directed and produced by Doron Paz and Yoav Paz, adapted the plot for cinema.


title: Evan Stone

text: In 2011, Stone became the third actor in history to receive the AVN Award for Male Performer of the Year three times. That same year, he was listed by CNBC as one of the twelve most popular stars in porn, being the only man to make the list. Stone has also been inducted into the AVN and XRCO Halls of Fame.


title: Evan Stone

text: Stone was born in Ames, Iowa. He was raised by his adoptive father, who worked as a firefighter, in Dallas, Texas. Stone is a 1982 graduate of Gobles High School in Gobles, Michigan. He played college football in the position of defensive lineman for the Western Michigan Broncos, a NCAA Division I team, but had to retire after suffering an injury. To make a living, he worked as a forklift driver, gas station attendant, dinner theatre performer, mechanic, and slaughterman at JBS.


title: Evan Stone

text: Stone entered the sex industry as an exotic dancer, which he did for ten years. In 1997, he began performing in adult films. Stone appeared as the monster in the 2001 parody film "Hung Wankenstein". On January 1, 2001, he received the award for Male Performer of the Year at the 18th AVN Awards.


title: Evan Stone

text: In February 2005, Stone replaced Julian as host of the cable television program "Spice Hotel" on Friday, Saturday, and Sunday evenings on Spice Live. The program focused on porn star couples. At the 25th AVN Awards, Stone received the honor of Male Performer of the Year for a second time.


title: Evan Stone

text: On February 1, 2009, a 37-second clip of actress Tristan Kingsley performing oral sex on Stone, from the 2008 adult film "Wild Cherries 5", was broadcast during Super Bowl XLIII to various Comcast subscribers in Tucson, Arizona. Comcast reported a significant economic loss due to the incident, and issued a monetary credit to approximately 80,000 subscribers. Following the incident, Stone reported that his website started averaging 20,000 hits daily.


title: Evan Stone

text: In 2011, he was named by CNBC as one of the twelve most popular stars in porn, being the only man on the list. That same year, he received his third win for Male Performer of the Year at the 28th AVN Awards, becoming only the third performer in history to do so, after Lexington Steele and Manuel Ferrara, respectively. Months later, he made his directorial debut with the Hustler film "TSA - Your Ass Is in Our Hands".


title: Interstate 70

text: Interstate 70 (I-70) is a major east–west Interstate Highway in the United States that runs from I-15 near Cove Fort, Utah, to a park and ride lot just east of I-695 in Baltimore, Maryland, and is the fifth-longest Interstate in the country. I-70 approximately traces the path of U.S. Route 40 (US 40, the old National Road) east of the Rocky Mountains. West of the Rockies, the route of I-70 was derived from multiple sources. The Interstate runs through or near many major cities, including Denver, Topeka, Kansas City, St. Louis, Indianapolis, Columbus, Pittsburgh, and Baltimore. The sections of the Interstate in Missouri and Kansas have laid claim to be the first Interstate in the United States. The Federal Highway Administration (FHWA) has claimed the section of I-70 through Glenwood Canyon, Colorado, completed in 1992, to be the last piece of the Interstate Highway System, as originally planned, to open to traffic. The construction of I-70 in Colorado and Utah is considered an engineering marvel, as the route passes through the Eisenhower Tunnel, Glenwood Canyon, and the San Rafael Swell. The Eisenhower Tunnel is the highest point along the Interstate Highway System, with an elevation of .


title: Interstate 70

text: I-70 begins at an interchange with I-15 near Cove Fort. Heading east, I-70 crosses between the Tushar and Pahvant ranges via Clear Creek Canyon and descends into the Sevier Valley, where I-70 serves Richfield, the only town of more than a few hundred people along I-70's path in Utah. Upon leaving the valley near Salina, I-70 crosses the Salina Summit and then crosses a large geologic formation called the San Rafael Swell.


title: Interstate 70

text: Prior to the construction of I-70, the swell was inaccessible via paved roads and relatively undiscovered. Once this section was opened to traffic in 1970, it became the longest stretch of Interstate Highway with no services and the first highway in the US built over a completely new route since the Alaska Highway. It also became the longest piece of Interstate Highway to be opened at one time. Although opened in 1970, this section was not formally complete until 1990, when a second steel arch bridge spanning Eagle Canyon was opened to traffic.


title: Interstate 70

text: Since I-70's construction, the swell has been noted for its desolate beauty. The swell has since been nominated for national park or national monument status on multiple occasions. If the swell is granted this status, it arguably would be the first time a national park owes its existence to an Interstate Highway. Most of the exits in this span are rest areas, brake check areas, and runaway truck ramps with few traditional freeway exits.


title: Interstate 70

text: I-70 exits the swell near Green River. From Green River to the Colorado state line, I-70 follows the southern edge of the Book Cliffs.


title: Interstate 70

text: Entering from Utah, I-70 descends into the Grand Valley, where it meets the Colorado River, which provides its path up the western slope of the Rocky Mountains. Here I-70 serves the Grand Junction metro area before traversing more mountainous terrain.


title: Interstate 70

text: The last section of I-70 to be completed was the Glenwood Canyon. This stretch was completed in 1992 and was an engineering marvel, due to the extremely difficult terrain and narrow space in the canyon, which requires corners that are sharper than normal Interstate standards. Construction was delayed for many years due to environmental concerns. The difficulties in building the road in the canyon were compounded by the fact the Denver & Rio Grande Western Railroad occupied the south bank, and many temporary construction projects took place to keep US 6 open, at the time the only east–west road in the area. Much of the highway is elevated above the Colorado River. The speed limit in this section is , due to the limited sight distance and sharp corners.


title: Interstate 70

text: The Eisenhower–Johnson Memorial Tunnel, the highest vehicular tunnel in North America and the longest tunnel built under the Interstate program, passes through the Continental Divide.


title: Interstate 70

text: Descending through the eastern foothills of the Rocky Mountains, one can see the Denver skyline on a clear day. This can fool truckers and other unsuspecting drivers, because one must still traverse of steep grade road before reaching the city. A series of signs warns truckers of the steep grade. As I-70 leaves the foothills, it goes through Denver and intersects I-25, serving as the central east–west artery through the city. Leaving Denver, I-70 levels out and traverses the wide plains through eastern Colorado. East of Denver, I-70 makes a broad turn to the south-southeast for before reaching Limon and resuming its eastward journey toward Kansas.


title: Interstate 70

text: Coming from Colorado, I-70 enters the prairie, farmlands, and rolling hills of Kansas. This portion of I-70 was the first segment to start being paved and to be completed in the Interstate Highway System. It is given the nickname "Main Street of Kansas", as the Interstate extends from the western border to the eastern border of the state, covering and passing through most of the state's principal cities in the process.


title: Interstate 70

text: In Salina, I-70 intersects with I-135, the longest "spur" route in the Interstate System, forming the latter's northern terminus.


title: Interstate 70

text: In Topeka, I-70 intersects I-470, twice. At the eastern intersection, the Kansas Turnpike merges, with I-70 becoming a toll road. This is one of only two sections of I-70 that are tolled. (The other is part of the Pennsylvania Turnpike.) I-70 carries this designation from Topeka to Kansas City, the eastern terminus of the turnpike. About halfway between Topeka and Kansas City, Kansas, I-70 passes through Lawrence (home to the University of Kansas). The tolled portion of the turnpike ends near Bonner Springs, just west of Kansas City. There is also a third child route in Topeka, I-335, which runs from I-470 south to meet up with I-35 in the Flint Hills town of Emporia. Just past the Bonner Springs Toll Plaza I-70 crosses I-435 for the first time, which allows travelers to bypass the downtown traffic via I-435, which encircles the Kansas City metropolitan area. Further down the highway in Kansas City, Kansas, approximately before the 18th Street Expressway, I-70 is intersected again by another child route. This route, I-635, runs from I-35 at its southern terminus up to I-29, just about across the Missouri River, at its northern terminus. From I-635 to just past the 7th Street (US 169) exit, I-70 runs adjacent Union Pacific's Armourdale Yard. Here I-670 (also designated "Alternate 70" on some signs) diverges, providing a more direct route that rejoins I-70 proper a few miles east in Missouri. The highway passes over the former stockyards and railyard when it crosses the Kansas River on the Lewis and Clark Viaduct into Downtown Kansas City, Missouri.


title: Interstate 70

text: After crossing the Lewis and Clark Viaduct, I-70 enters Missouri. It encounters a loop of freeways, called the Alphabet Loop, which contains I-70 as well as I-35, I-670, US 24, US 40, US 71, and US 169. In the southern part of this loop, I-670 cuts directly through the downtown while I-70 bypasses the taller buildings a few blocks north near the Missouri River. Westbound I-670 is also designated Alternate I-70. Most of the Interstates in this loop are in their second mile, so all exits (no matter which Interstate carries the road) are numbered 2 and suffixed with every letter of the alphabet except for I, O, and Z.


title: Interstate 70

text: The section of I-70 in Downtown Kansas City is approximately the southern city limits of "City of Kansas" when it was incorporated in 1853. The first two auto bridges in Missouri mark the city's original boundaries with the Buck O'Neil Bridge (US 169) being the west boundary while the Heart of America Bridge (Route 9) is the east boundary. Another intersection of note is the second traverse of I-435. This is primarily notable because it immediately precedes the Truman Sports Complex (home of both Arrowhead Stadium and Kauffman Stadium) and also because the entrance ramps from I-435 northbound onto I-70 eastbound also serve as the exit ramps from I-70 into the Truman Sports Complex parking lots. This section of the Interstate is marked as the "George Brett Super Highway", named after the Kansas City Royals third baseman who played the entirety of his career (1973–1993) at the K. The last Interstate intersection in the immediate Kansas City metro area is with I-470 in Independence.


title: Interstate 70

text: After passing Kansas City, I-70 traverses the length of Missouri, west to east. It passes through the largest city between Kansas City and St. Louis, Columbia, which is about halfway between the two major cities, and the home of the University of Missouri. The terrain is rolling with some hills and bluffs near rivers. I-70 also crosses the Missouri River twice (as did the original US 40)—at Rocheport, about west of Columbia, and at St. Charles, about northwest of St. Louis. Most of the highway on this stretch is four-lane. Various proposals have been made to widen it (at an estimated cost of $3.5 billion) including turning it into a toll road. I-70 eventually gets into Greater St. Louis and US 40 splits to the south, along with US 61, which does not have a concurrency with I-70. In late 2009, the intersecting road was upgraded to Interstate standards along with the completion of the overhaul of I-64. After this interchange, I-70 intersects two child routes, I-270 and I-170. After passing several bedroom communities in north St. Louis County, I-70 enters the city limits of St. Louis. It turns east to cross the Mississippi River on the Stan Musial Veterans Memorial Bridge, connecting with an extension of I-44, which takes the former I-70 route through Downtown St. Louis to meet I-55 at its connection to the Poplar Street Bridge.


title: Interstate 70

text: The 1985 World Series between the Kansas City Royals and St. Louis Cardinals was nicknamed the "I-70 Series" because St. Louis and Kansas City are the two endpoints of I-70 in Missouri, and the highway passes within sight of both the Royals' Kauffman Stadium and, at the time, the Cardinals' Busch Stadium.


title: Interstate 70

text: After crossing the Stan Musial Veterans Memorial Bridge, I-70 merges with I-55, while I-64 splits off I-55. When the routes intersect I-270, I-55 stays on its own pavement using the mileposts from the Poplar Street Bridge, while I-70 heads east on I-270's pavement using I-270's mileposts. Because of this, when I-55/I-70 intersects I-270 from the southeast, the exit number is 20 and, in the opposite direction, it is exit 15.


title: Interstate 70

text: I-70 was rerouted from the Poplar Street Bridge to the Stan Musial Veterans Memorial Bridge north of Downtown St. Louis, which opened in February 2014.


title: Interstate 70

text: I-70 passes through numerous county seats in Illinois, among them Vandalia, the state capital from 1818 to 1839. It runs concurrently with I-57 around Effingham, then proceeds east toward Indiana.


title: Interstate 70

text: I-70 enters Indiana just to the west of Terre Haute and then crosses the Wabash River before skirting the city's south side. After passing through miles of gently rolling terrain in rural west-central Indiana, the freeway approaches the major metropolitan area of Indianapolis.


title: Interstate 70

text: The main entrance to Indianapolis International Airport was relocated to I-70's exit 68 on November 11, 2008. Upon nearing the central business district of Indiana's capital city, the visages of Lucas Oil Stadium and the newly constructed (in 2011) JW Marriott Indianapolis hotel, with the city's skyline as their backdrop, now dominate the view to the north from the freeway. After passing just to the south of the world headquarters for Eli Lilly and Company, I-70 and I-65 have a brief concurrency through the eastern side of Downtown Indianapolis. The junction points of these two major routes are known locally as the "South Split" and "North Split", respectively.


title: Interstate 70

text: It is also noteworthy the other two-digit Interstates serving Indianapolis do not reach the city's core. As a result, I-70 motorists must use the I-465 beltway in order to reach I-69 without leaving the Interstate System, while those similarly bound for I-74 access that route via its concurrency around the southern portion of the I-465 loop.


title: Interstate 70

text: After passing through much of the near northeast side of Indianapolis, I-70 again encounters the I-465 beltway (which carries a multitude of unsigned U.S. Routes and Indiana state highways). I-70 continues on nearly due east from this point, first traveling through suburban Indianapolis, then transitioning into rural east central Indiana, where it passes just to the south of New Castle. Upon reaching the Richmond area, US 35 joins I-70 just before both routes leave the Hoosier State together and enter Ohio.


title: Interstate 70

text: I-70 enters Ohio just east of the interchange with US 40 at Richmond, Indiana. Immediately to the east of this border, travelers notice a unique teal-blue arch that spans the width of the freeway, with a "Welcome to Ohio" greeting sign above the eastbound lanes. A sign thanking travelers for visiting Ohio is mounted on the other side of the arch for westbound travelers. Continuing eastbound, I-70 intersects I-75 north of Dayton, followed by I-675 on the east side of Dayton. Springfield is the next city, site of Buck Creek State Park.


title: Interstate 70

text: I-70 then encounters Columbus. Columbus is bounded by I-270, and is roughly centered on the intersection of I-70 and I-71, which share the same asphalt through a notoriously congested stretch locally known as the "South Innerbelt" or, more commonly, "The Split". This stretch has I-71 concurrent with I-70, where I-71 enters and exits from opposite sides of I-70, causing traffic getting on I-70 from I-71 northbound to have to cross four lanes of I-70 traffic to continue on I-71. A similar issue is present for southbound I-71 traffic as well. The Split will be reconstructed within the next few years. I-670 connects John Glenn Columbus International Airport with I-270, I-71, and I-70. East of Columbus, I-70 passes through Zanesville and on to Cambridge, where it intersects I-77. Continuing on toward West Virginia, I-70 intersects I-470 just east of St. Clairsville. I-470 is primarily used for through traffic and to avoid The Festival of Lights traffic during the Christmas season. In March 1995, a hole (from a former coal mine) opened up on the eastbound side of I-70 in Guernsey County near Old Washington and caused traffic to be rerouted onto US 40 between Old Washington and Cambridge for several months.


title: Interstate 70

text: The portion of I-70 in West Virginia crosses the Ohio River at Wheeling and runs through the Wheeling Tunnel. I-70 has only one throughlane in each direction at the tunnel. A major interchange was planned but never completed on the east side of the Wheeling Tunnel. Upon merging with I-470, I-70 goes uphill toward Dallas Pike, West Virginia, This part of the road is called "Two Mile Hill", which is known locally for the many accidents at the bottom of the hill. I-70 has brought major development in Ohio County, the only county the route passes through in West Virginia, in the past few years. On the north side of the highway, a former strip mine was developed into a retail area called The Highlands. This stretch of I-70 is the shortest that I-70 is in any state, traveling only from the Ohio River to the Pennsylvania border.


title: Interstate 70

text: I-70 was initially envisioned to go through Downtown Pittsburgh but now goes south of it. Its originally planned route was later incorporated into I-376, as well as parts of I-76 and I-79. I-70 also overlaps I-79 near the Pittsburgh suburb of Washington for .


title: Interstate 70

text: The of I-70 between Washington and New Stanton is a substandard section of the highway. This section of I-70 used to be Pennsylvania Route 71 (PA 71). It is characterized by sharp curves, limited sight distance, narrow shoulders, and lack of merge lanes at interchanges. Traffic on cloverleaf ramps must weave in the right throughlane of traffic due to the lack of a third lane for entering and exiting traffic. Other on- and offramps effectively function as right-in/right-out interchanges, forcing vehicles to weave in and out of the exit lane. The speed limit on this stretch is .


title: Interstate 70

text: From New Stanton to Breezewood, I-70 overlaps I-76 and the Pennsylvania Turnpike. This is one of only two tolled sections of I-70 (the other is in Kansas, where the portion of the Kansas Turnpike east of Topeka is signed I-70).


title: Interstate 70

text: Drivers on I-70 near Breezewood have to leave the freeway and travel a few blocks on US 30 past several traffic-lights before returning to the freeway. This stretch of I-70 is one of the few gaps on the Interstate Highway System.


title: Interstate 70

text: I-70 continues on almost due south to the Maryland border after leaving I-76 (Pennsylvania Turnpike) at Breezewood. This section is posted at and is heavily patrolled. After the border, it meets I-68's eastern end and turns east toward Baltimore and Washington, D.C.


title: Interstate 70

text: In Maryland, I-70 runs from the Pennsylvania state line near Hancock east across the central portion of the state toward Baltimore, following the route of the National Road, now known as US 40. It is a major east–west highway in the state, serving the cities of Hagerstown and Frederick and bypassing Ellicott City. East of Frederick, the route was originally designated Interstate 70N (I-70N). The highway serves Washington, D.C., via I-270, which was once designated Interstate 70S (I-70S) Uniquely, I-70 indirectly serves a branch of the Washington Metro at Shady Grove via I-370, which only connects to I-270.


title: Interstate 70

text: I-70 was planned to end at I-95 in Baltimore, but due to local opposition, it was only built to Maryland Route 122 (MD 122).


title: Interstate 70

text: Besides being the first Interstate to receive a contract for pavement, other oddities happened with I-70 as well.


title: Interstate 70

text: As first proposed, the western terminus of I-70 was to be Denver. However, Utah and Colorado pressured the federal government to extend the planned freeway farther west, arguing a direct link between Denver and Salt Lake City was vital for an effective highway system. The proposal was to follow what is now US 6 west and connect to I-15 at Spanish Fork, Utah. Federal planners (influenced by the military) agreed to extend the proposed route of I-70, but not to serve Salt Lake City; the military wanted to better connect Southern California with the Northeast. This led to I-70's constructed route through the San Rafael Swell terminating at Cove Fort. Many motorists include I-70 as part of their cross-country drives between New York City and Los Angeles (which are accessible to I-70 via other Interstates).


title: Interstate 70

text: As a result of freeway revolts in the Baltimore area, I-70 was not completed east of MD 122 to its planned terminus at I-95 within the city of Baltimore, and it now ends at a four-way symmetrical stack interchange with I-695, the Baltimore Beltway. Until November 2014, I-70 ended at a park and ride lot at MD 122 as the freeway enters the city of Baltimore at exit 94. Commuters park on the pavement where high-speed freeway lanes were to be. The former freeway from I-695 to MD 122 is being converted into a two-lane parkway to be renamed Cooks Boulevard, maintained by the Maryland State Highway Administration.


title: Interstate 70

text: The highway gave its name to the I-70 killer, a serial killer who committed a string of murders within a few miles of it in several Midwestern states in the early 1990s. No suspect has ever been apprehended despite the widespread publicity the murders generated, including their being featured several times on the television show "America's Most Wanted" and "Unsolved Mysteries".


title: Interstate 70

text: John Allen Muhammad and Lee Boyd Malvo, the duo responsible for the D.C. sniper attacks, were apprehended at a rest stop on I-70 near Myersville, Maryland, in 2002.


title: Interstate 70

text: The 1985 World Series was a contest between the St. Louis Cardinals and the Kansas City Royals and won by the Royals. As these cities are primarily connected by I-70, the media often called series the I-70 Series.


title: Interstate 70

text: I-70 has one of the closest distances between two distinct child Interstates with the same child Interstate number. I-470 near Topeka, Kansas, and I-470 on the east side of Kansas City, Missouri, are approximately apart. This record is surpassed by I-291 around Hartford, Connecticut, and I-291 near Springfield, Massachusetts, which are unrelated but are apart.


title: Sand tiger shark

text: The sand tiger shark (Carcharias taurus), gray nurse shark, spotted ragged-tooth shark or blue-nurse sand tiger, is a species of shark that inhabits subtropical and temperate waters worldwide. It inhabits the continental shelf, from sandy shorelines (hence the name sand tiger shark) and submerged reefs to a depth of around . They dwell in the waters of Japan, Australia, South Africa, and the east coasts of North and South America. The sand tiger shark also inhabited the Mediterranean, however it was last seen there in 2003 and is presumed extinct in the region. Despite its common names, it is not closely related to either the tiger shark ("Galeocerdo cuvier") or the nurse shark ("Ginglymostoma cirratum").


title: Sand tiger shark

text: Despite its fearsome appearance and strong swimming ability, it is a relatively placid and slow-moving shark with no confirmed human fatalities. This species has a sharp, pointy head, and a bulky body. The sand tiger's length can reach but is normally 2.2–2.5 m in length. They are grey with reddish-brown spots on their backs. Shivers (groups) have been observed to hunt large schools of fish. Their diet consists of bony fish, crustaceans, squid, skates and other sharks. Unlike other sharks, the sand tiger can gulp air from the surface, allowing it to be suspended in the water column with minimal effort. During pregnancy, the most developed embryo will feed on its siblings, a reproductive strategy known as intrauterine cannibalism i.e. "embryophagy" or, more colorfully, adelphophagy—literally "eating one's brother". The sand tiger is categorized as critically endangered on the International Union for Conservation of Nature Red List. It is the most widely kept large shark in public aquariums owing to its tolerance for captivity.


title: Sand tiger shark

text: The sand tiger shark's description as "Carcharias taurus" by Constantine Rafinesque came from a specimen caught off the coast of Sicily. "Carcharias taurus" means "bull shark". This taxonomic classification has been long disputed. Twenty-seven years after Rafinesque's original description the German biologists Müller and Henle changed the genus name from "C. taurus" to "Triglochis taurus". The following year, Swiss-American naturalist Jean Louis Rodolphe Agassiz reclassified the shark as "Odontaspis cuspidata" based on examples of fossilized teeth. Agassiz's name was used until 1961 when three palaeontologists and ichthyologists, W. Tucker, E. I. White, and N. B. Marshall, requested that the shark be returned to the genus "Carcharias". This request was rejected and "Odontaspis" was approved by the International Code of Zoological Nomenclature (ICZN). When experts concluded that "taurus" belongs after "Odontaspis", the name was changed to "Odontaspis taurus". In 1977, Compagno and Follet challenged the "Odontaspis taurus" name and substituted "Eugomphodus", a somewhat unknown classification, for "Odontaspis". Many taxonomists questioned his change, arguing that there was no significant difference between "Odontaspis" and "Carcharias". After changing the name to "Eugomphodus taurus", Compagno successfully advocated in establishing the shark's current scientific name as "Carcharias taurus". The ICZN approved this name, and today it is used among biologists.


title: Sand tiger shark

text: Because the sand tiger shark is worldwide in distribution, it has many common names. The term "sand tiger shark" actually refers to four different sand tiger shark species in the family Odontaspididae. Furthermore, the name creates confusion with the unrelated tiger shark "Galeocerdo cuvier". The "grey nurse shark", the name used in Australia, is the second-most used name for the shark, and in India it is known as "blue-nurse sand tiger". However, there are unrelated nurse sharks in the family Ginglymostomatidae. The most unambiguous and descriptive English name is probably the South African one, "spotted ragged-tooth shark".


title: Sand tiger shark

text: The most likely problem when identifying the sand tiger shark is when in the presence of either of the two species of "Odontaspis". Firstly, the sand tiger is usually spotted, especially on the hind half of the body. However, there are several other differences that are probably more reliable:


title: Sand tiger shark

text: Adult sand tigers range from to in length with most specimens reaching a length of around 2.2–2.5 m and to in weight. The head is pointy, as opposed to round, while the snout is flattened with a conical shape. Its body is stout and bulky and its mouth extends beyond the eyes. The eyes of the sand tiger shark are small, lacking eyelids. A sand tiger usually swims with its mouth open displaying three rows of protruding, smooth-edged, sharp-pointed teeth. The males have grey claspers with white tips located on the underside of their body. The caudal fin is elongated with a long upper lobe (i.e. strongly heterocercal). They have two large, broad-based grey dorsal fins set back beyond the pectoral fins. The sand tiger shark has a grey-brown back and pale underside. Adults tend to have reddish-brown spots scattered, mostly on the hind part of the body. In August 2007, an albino specimen was photographed off South West Rocks, Australia. The teeth of these sharks have no transverse serrations (as have many other sharks) but they have a large, smooth main cusp with a tiny cusplet on each side of the main cusp. The upper front teeth are separated from the teeth on the side of the mouth by small intermediate teeth.


title: Sand tiger shark

text: Sand tiger sharks roam the epipelagic and mesopelagic regions of the ocean, sandy coastal waters, estuaries, shallow bays, and rocky or tropical reefs, at depths of up to .


title: Sand tiger shark

text: The sand tiger shark can be found in the Atlantic, Pacific and Indian Oceans, and in the Adriatic Seas. In the Western Atlantic Ocean, it is found in coastal waters around from the Gulf of Maine to Florida, in the northern Gulf of Mexico, around the Bahamas and Bermuda, and from southern Brazil to northern Argentina. It is also found in the eastern Atlantic Ocean from the Mediterranean Sea to the Canary Islands, at the Cape Verde islands, along the coasts of Senegal and Ghana, and from southern Nigeria to Cameroon. In the western Indian Ocean, the shark ranges from South Africa to southern Mozambique, but excluding Madagascar. The sand tiger shark has also been sighted in the Red Sea and may be found as far east as India. In the western Pacific, it has been sighted in the waters around the coasts of Japan and Australia, but not around New Zealand.


title: Sand tiger shark

text: Sand tigers in South Africa and Australia undertake an annual migration that may cover more than . They pup during the summer in relatively cold water (temperature ca. ). After parturition, they swim northwards toward sites where there are suitable rocks or caves, often at a water depth ca. , where they mate during and just after the winter. Mating normally takes place at night. After mating, they swim further north to even warmer water where gestation takes place. In the Autumn they return southwards to give birth in cooler water. This round trip may encompass as much as . The young sharks do not take part in this migration, but they are absent from the normal birth grounds during winter: it is thought that they move deeper into the ocean. At Cape Cod (USA), juveniles move away from coastal areas when water temperatures decreases below 16 °C and day length decreases to less than 12 h. Juveniles, however, return to their usual summer haunts and as they become mature they start larger migratory movements.


title: Sand tiger shark

text: The sand tiger shark is a nocturnal feeder. During the day, they take shelter near rocks, overhangs, caves and reefs often at relatively shallow depths (<20 m). This is the typical environment where divers encounter sand tigers, hovering just above the bottom in large sandy gutters and caves. However, at night they leave the shelter and hunt over the ocean bottom, often ranging far from their shelter. Sand tigers hunt by stealth. It is the only shark known to gulp air and store it in the stomach, allowing the shark to maintain near-neutral buoyancy which helps it to hunt motionlessly and quietly. Aquarium observations indicate that when it comes close enough to a prey item, it grabs with a quick sideways snap of the prey. The sand tiger shark has been observed to gather in hunting groups when preying upon large schools of fish.


title: Sand tiger shark

text: The majority of prey items of sand tigers are demersal (i.e. from the sea bottom), suggesting that they hunt extensively on the sea bottom as far out as the continental shelf. Bony fish (teleosts) form about 60% of sand tigers' food, the remaining prey comprising sharks, skates, other rays, lobsters, crabs and squid. In Argentina, the prey includes mostly demersal fishes, e.g. the striped weakfish ("Cynoscion guatucupa") and whitemouth croaker ("Micropogonias furnieri"). The most important elasmobranch prey is the bottom-living narrownose smooth-hound shark ("Mustelus schmitti."). Benthic (i.e. free-swimming) rays and skates are also taken, including fanskates, eagle rays and the angular angel shark, with larger individuals feeding on a higher number of benthic elasmobranchs than smaller individuals. Stomach content analysis indicates that smaller sand tigers mainly focus on the sea bottom and as they grow larger they start to take more benthic prey. This perspective of the diet of sand tigers is consistent with similar observations in the north west Atlantic and in South Africa where large sand tigers capture a wider range of shark and skate species as prey, from the surf zone to the continental shelf, indicating the opportunistic nature of sand tiger feeding. Off South Africa, sand tigers less than in length prey on fish about a quarter of their own length; however, large sand tigers capture prey up to about half of their own length. The prey items are usually swallowed as three or four chunks.


title: Sand tiger shark

text: in the northern hemisphere and during August–October in the southern hemisphere. The courtship and mating of sand tigers has been best documented from observations in large aquaria. In Oceanworld, Sydney, the females tended to hover just above the sandy bottom ("shielding") when they were receptive. This prevented males from approaching from underneath towards their cloaca. Often there is more than one male close by with the dominant one remaining close to the female, intimidating others with an aggressive display in which the dominant shark closely follows the tail of the subordinate, forcing the subordinate to accelerate and swim away. The dominant male snaps at smaller fish of other species. The male approaches the female and the two sharks protect the sandy bottom over which they interact. Strong interest of the male is indicated by superficial bites in the anal and pectoral fin areas of the female. The female responds with superficial biting of the male. This behaviour continues for several days during which the male patrols the area around the female. The male regularly approaches the female in "nosing" behaviour to "smell" the cloaca of the female. If she is ready, she swims off with the male, while both partners contort their bodies so that the right clasper of the male enters the cloaca of the female. The male bites the base of her right pectoral fin, leaving scars that are easily visible afterwards. After one or two minutes, mating is complete and the two separate. Females often mate with more than one male. Females mate only every second or third year. After mating, the females remain behind, while the males move off to seek other areas to feed, resulting in many observations of sand tiger populations comprising almost exclusively females.


title: Sand tiger shark

text: The reproductive pattern is similar to that of many of the Lamnidae, the shark family to which sand tigers belong. Female sand tigers have two uterine horns that, during early embryonic development, may have as many as 50 embryos that obtain nutrients from their yolk sacs and possibly consume uterine fluids. When one of the embryos reaches some in length, it eats all the smaller embryos so that only one large embryo remains in each uterine horn, a process called intrauterine cannibalism i.e. "embryophagy" or, more colorfully, adelphophagy—literally "eating one's brother." While multiple male sand tigers commonly fertilize a single female, adelphophagy sometimes excludes all but one of them from gaining offspring. These surviving embryos continue to feed on a steady supply of unfertilised eggs. After a lengthy labour, the female gives birth to long, fully independent offspring. The gestation period is approximately eight to twelve months. These sharks give birth only every second or third year, resulting in an overall mean reproductive rate of less than one pup per year, one of the lowest reproductive rates for sharks.


title: Sand tiger shark

text: In the north Atlantic, sand tiger sharks are born about 1 m in length. During the first year, they grow about 27 cm to reach 1.3 m. After that, the growth rate decreases by about 2.5 cm each year until it stabilises at about 7 cm/y. Males reach sexual maturity at an age of five to seven years and approximately in length. Females reach maturity when approximately long at about seven to ten years of age. They are normally not expected to reach lengths over 3 m and lengths around 2.2–2.5 is more common. In the informal media, such as YouTube, there have been several reports of sand tigers around 5 m long, but none of these have been verified scientifically.


title: Sand tiger shark

text: The sand tiger is often wrongly associated with being vicious or deadly, due to its relatively large size and sharp, protruding teeth that point outward from its jaws; however, these sharks are quite docile, and are not a threat to humans. Their mouths are not large enough to cause a human fatality. Sand tigers roam the surf, sometimes in close proximity to humans, and there have been only a few instances of unprovoked sand tiger shark attacks on humans, usually associated with spear fishing, line fishing, or shark feeding. As of 2013, the database of Shark Attack Survivors does not list any fatalities due to sand tiger sharks. When the sharks become aggressive, they tend to steal fish or bait from fishing lines rather than attack humans. Owing to its large size and docile temperament, the sand tiger is commonly displayed in aquariums around the world.


title: Sand tiger shark

text: In Australia and South Africa, one of the common practices in beach holiday areas is to erect shark nets around the beaches frequently used by swimmers. These nets are erected some from the shore and act as gill nets that trap incoming sharks: this was the norm until about 2005. In South Africa, the mortality of sand tiger sharks caused a significant decrease in the length of these animals and it was concluded that the shark nets pose a significant threat to this species with its very low reproductive rate Before 2000, these nets snagged about 200 sand tiger sharks per year in South Africa, of which only about 40% survived and were released alive. The efficiency of shark nets for the prevention of unprovoked shark attacks on bathers has been questioned, and since 2000 there has been a reduced use of these nets and alternative approaches are being developed.


title: Sand tiger shark

text: In Argentina, the prey items of sand tigers largely coincided with important commercial fisheries targets. Humans affect sand tiger food availability and the sharks, in turn, compete with humans for food that, in turn, has already been heavily exploited by the fisheries industry. The same applies to the bottom-living sea catfish ("Galeichthys feliceps"), a fisheries resource off the South African coast.


title: Sand tiger shark

text: Sand tiger sharks are often the targets of scuba divers who wish to observe or photograph these animals. A study near Sydney in Australia found that the behaviour of the sharks is affected by the proximity of scuba divers. Diver activity affects the aggregation, swimming and respiratory behaviour of sharks, but only at short time scales. The group size of scuba divers was less important in affecting sand tiger behaviour than the distance within which they approached the sharks. Divers approaching to within 3 m of sharks affected their behaviour but after the divers had retreated, the sharks resumed normal behaviour. Other studies indicate sand tiger sharks can be indifferent to divers. Scuba divers are normally compliant with Australian shark-diving regulations.


title: Sand tiger shark

text: Its large and menacing appearance, combined with its relative placidity, has made the sand tiger shark among the most popular shark species to be displayed in public aquaria. However, as with all large sharks, keeping them in captivity is not without its difficulties. Sand tiger sharks have been found to be highly susceptible to developing spinal deformities, with as many as one in every three captive sharks being affected, giving them a hunched appearance. These deformities have been hypothesized to be correlated to both the size and shape of their tank. If the tank is too small, the sharks have to spend more time actively swimming than they would in the wild, where they have space to glide. Also, sharks in small, circular tanks often spend most of their time circling along the edges in only one direction, causing asymmetrical stress on their bodies.


title: Sand tiger shark

text: There are several factors contributing to the decline in the population of the sand tigers. Sand tigers reproduce at an unusually low rate, due to the fact that they do not have more than two pups at a time and because they breed only every second or third year. This shark is a highly prized food item in the western northern Pacific, off Ghana and off India and Pakistan where they are caught by fishing trawlers, although they are more commonly caught with a fishing line. Sand tigers' fins are a popular trade item in Japan. Off North America, it is fished for its hide and fins. Shark liver oil is a popular product in cosmetic products such as lipstick. It is sought by anglers in fishing competitions in South Africa and some other countries. In Australia it has been reduced in numbers by spear fishers using poison and where it is now protected. It is also prized as an aquarium exhibit in the United States, Europe, Australia and South Africa because of its docile and hardy nature. Thus, overfishing is a major contributor to the population decline. All indications show that the world population in sand tigers has been reduced significantly in size since 1980. Many sand tigers are caught in shark nets, and then either strangled or taken by fishermen. Estuaries along the United States of America's eastern Atlantic coast houses many of the young sand tiger sharks. These estuaries are susceptible to non-point source pollution that is harmful to the pups. In Eastern Australia, the breeding population was estimated to be fewer than 400 reproductively mature animals, a number believed to be too small to sustain a healthy population.


title: Sand tiger shark

text: This species is therefore listed as Critically Endangered on the International Union for Conservation of Nature Red List, and as "endangered" under Queensland's Nature Conservation Act 1992. It is a U.S. National Marine Fisheries Service "[Species of Concern]", which are those species that the U.S. Government's National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NMFS), has some concerns regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the U.S. Endangered Species Act. According to the National Marine Fisheries Service, any shark caught must be released immediately with minimal harm, and is considered a prohibited species, making it illegal to harvest any part of the sand tiger shark on the United States' Atlantic coast.


title: Sand tiger shark

text: A recent report from the Pew Charitable Trusts suggests that a new management approach used for large mammals that have suffered population declines could hold promise for sharks. Because of the life-history characteristics of sharks, conventional fisheries management approaches, such as reaching maximum sustainable yield, may not be sufficient to rebuild depleted shark populations. Some of the more stringent approaches used to reverse declines in large mammals may be appropriate for sharks, including prohibitions on the retention of the most vulnerable species and regulation of international trade.


title: Microtubule

text: Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 and 15 nm. They are formed by the polymerization of a dimer of two globular proteins, alpha and beta tubulin into protofilaments that can then associate laterally to form a hollow tube, the microtubule. The most common form of a microtubule consists of 13 protofilaments in the tubular arrangement.


title: Microtubule

text: Microtubules play an important role in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organelles, and intracellular macromolecular assemblies. They are also involved in cell division (by mitosis and meiosis) and are the main constituents of mitotic spindles, which are used to pull eukaryotic chromosomes apart.


title: Microtubule

text: Microtubules are nucleated and organized by microtubule-organizing centres, such as the centrosome found in the center of many animal cells or the basal bodies of cilia and flagella, or the spindle pole bodies found in most fungi.


title: Microtubule

text: There are many proteins that bind to microtubules, including the motor proteins dynein and kinesin, microtubule-severing proteins like katanin, and other proteins important for regulating microtubule dynamics. Recently an actin-like protein has been found in the gram-positive bacterium "Bacillus thuringiensis", which forms a microtubule-like structure called a nanotubule, involved in plasmid segregation. Other bacterial microtubules have a ring of five protofilaments.


title: Microtubule

text: Tubulin and microtubule-mediated processes, like cell locomotion, were seen by early microscopists, like Leeuwenhoek (1677). However, the fibrous nature of flagella and other structures were discovered two centuries later, with improved light microscopes, and confirmed in the 20th century with the electron microscope and biochemical studies.


title: Microtubule

text: "In vitro" assays for microtubule motor proteins such as dynein and kinesin are researched by fluorescently tagging a microtubule and fixing either the microtubule or motor proteins to a microscope slide, then visualizing the slide with video-enhanced microscopy to record the travel of the motor proteins. This allows the movement of the motor proteins along the microtubule or the microtubule moving across the motor proteins. Consequently, some microtubule processes can be determined by kymograph.


title: Microtubule

text: In eukaryotes, microtubules are long, hollow cylinders made up of polymerised α- and β-tubulin dimers. The inner space of the hollow microtubule cylinders is referred to as the lumen. The α and β-tubulin subunits are ~50% identical at the amino acid level, and both have a molecular weight of approximately 50 kDa.


title: Microtubule

text: These α/β-tubulin dimers polymerize end-to-end into linear protofilaments that associate laterally to form a single microtubule, which can then be extended by the addition of more α/β-tubulin dimers. Typically, microtubules are formed by the parallel association of thirteen protofilaments, although microtubules composed of fewer or more protofilaments have been observed in various species  as well as "in vitro".


title: Microtubule

text: Microtubules have a distinct polarity that is critical for their biological function. Tubulin polymerizes end to end, with the β-subunits of one tubulin dimer contacting the α-subunits of the next dimer. Therefore, in a protofilament, one end will have the α-subunits exposed while the other end will have the β-subunits exposed. These ends are designated the (−) and (+) ends, respectively. The protofilaments bundle parallel to one another with the same polarity, so, in a microtubule, there is one end, the (+) end, with only β-subunits exposed, while the other end, the (−) end, has only α-subunits exposed. While microtubule elongation can occur at both the (+) and (−) ends, it is significantly more rapid at the (+) end.


title: Microtubule

text: The lateral association of the protofilaments generates a pseudo-helical structure, with one turn of the helix containing 13 tubulin dimers, each from a different protofilament. In the most common "13-3" architecture, the 13th tubulin dimer interacts with the next tubulin dimer with a vertical offset of 3 tubulin monomers due to the helicity of the turn. There are other alternative architectures, such as 11-3, 12-3, 14-3, 15-4, or 16-4, that have been detected at a much lower occurrence. Microtubules can also morph into other forms such as helical filaments, which are observed in protist organisms like foraminifera. There are two distinct types of interactions that can occur between the subunits of lateral protofilaments within the microtubule called the A-type and B-type lattices. In the A-type lattice, the lateral associations of protofilaments occur between adjacent α and β-tubulin subunits (i.e. an α-tubulin subunit from one protofilament interacts with a β-tubulin subunit from an adjacent protofilament). In the B-type lattice, the α and β-tubulin subunits from one protofilament interact with the α and β-tubulin subunits from an adjacent protofilament, respectively. Experimental studies have shown that the B-type lattice is the primary arrangement within microtubules. However, in most microtubules there is a seam in which tubulin subunits interact α-β.


title: Microtubule

text: The sequence and exact composition of molecules during microtubule formation can thus be summarised as follows: A β-tubulin connects in the context of a non-existent covalent bond with an α-tubulin, which in connected form are a heterodimer, since they consist of two different polypeptides (β-tubulin and α-tubulin). So after the heterodimers are formed, they join together to form long chains that rise figuratively in one direction (e.g. upwards). These heterodimers, which are connected in a certain direction, form protofilaments. These long chains (protofilaments) now gradually accumulate next to each other so that a tube-like structure is formed, which has a lumen typical of a tube. Accordingly, mostly 13 protofilaments form the outer wall of the microtubules. It is also important to note that the heterodimers consist of a positive and negative end, with alpha-tubulin forming the negative end and beta-tubulin the positive end. Due to the fact that the heterodimers are stacked on top of each other, there is always a negative and positive end. Microtubules grow by an addition of heterodimers at the plus end.


title: Microtubule

text: Some species of "Prosthecobacter" also contain microtubules. The structure of these bacterial microtubules is similar to that of eukaryotic microtubules, consisting of a hollow tube of protofilaments assembled from heterodimers of bacterial tubulin A (BtubA) and bacterial tubulin B (BtubB). Both BtubA and BtubB share features of both α- and β-tubulin. Unlike eukaryotic microtubules, bacterial microtubules do not require chaperones to fold. In contrast to the 13 protofilaments of eukaryotic microtubules, bacterial microtubules comprise only five.


title: Microtubule

text: Microtubules are part of the cytoskeleton, a structural network within the cell's cytoplasm. The roles of the microtubule cytoskeleton include mechanical support, organization of the cytoplasm, transport, motility and chromosome segregation. In developing neurons microtubules are known as neurotubules, and they can modulate the dynamics of actin, another component of the cytoskeleton. A microtubule is capable of growing and shrinking in order to generate force, and there are motor proteins that allow organelles and other cellular components to be carried along a microtubule. This combination of roles makes microtubules important for organizing and moving intracellular constituents.


title: Microtubule

text: The organization of microtubules in the cell is cell-type specific. In epithelia, the minus-ends of the microtubule polymer are anchored near the site of cell-cell contact and organized along the apical-basal axis. After nucleation, the minus-ends are released and then re-anchored in the periphery by factors such as ninein and PLEKHA7. In this manner, they can facilitate the transport of proteins, vesicles and organelles along the apical-basal axis of the cell. In fibroblasts and other mesenchymal cell-types, microtubules are anchored at the centrosome and radiate with their plus-ends outwards towards the cell periphery (as shown in the first figure). In these cells, the microtubules play important roles in cell migration. Moreover, the polarity of microtubules is acted upon by motor proteins, which organize many components of the cell, including the endoplasmic reticulum and the Golgi apparatus.


title: Microtubule

text: Nucleation is the event that initiates the formation of microtubules from the tubulin dimer. Microtubules are typically nucleated and organized by organelles called microtubule-organizing centres (MTOCs). Contained within the MTOC is another type of tubulin, γ-tubulin, which is distinct from the α- and β-subunits of the microtubules themselves. The γ-tubulin combines with several other associated proteins to form a lock washer-like structure known as the "γ-tubulin ring complex" (γ-TuRC). This complex acts as a template for α/β-tubulin dimers to begin polymerization; it acts as a cap of the (−) end while microtubule growth continues away from the MTOC in the (+) direction.


title: Microtubule

text: The centrosome is the primary MTOC of most cell types. However, microtubules can be nucleated from other sites as well. For example, cilia and flagella have MTOCs at their base termed basal bodies. In addition, work from the Kaverina group at Vanderbilt, as well as others, suggests that the Golgi apparatus can serve as an important platform for the nucleation of microtubules. Because nucleation from the centrosome is inherently symmetrical, Golgi-associated microtubule nucleation may allow the cell to establish asymmetry in the microtubule network. In recent studies, the Vale group at UCSF identified the protein complex augmin as a critical factor for centrosome-dependent, spindle-based microtubule generation. It that has been shown to interact with γ-TuRC and increase microtubule density around the mitotic spindle origin.


title: Microtubule

text: Some cell types, such as plant cells, do not contain well defined MTOCs. In these cells, microtubules are nucleated from discrete sites in the cytoplasm. Other cell types, such as trypanosomatid parasites, have a MTOC but it is permanently found at the base of a flagellum. Here, nucleation of microtubules for structural roles and for generation of the mitotic spindle is not from a canonical centriole-like MTOC.


title: Microtubule

text: Following the initial nucleation event, tubulin monomers must be added to the growing polymer. The process of adding or removing monomers depends on the concentration of αβ-tubulin dimers in solution in relation to the critical concentration, which is the steady state concentration of dimers at which there is no longer any net assembly or disassembly at the end of the microtubule. If the dimer concentration is greater than the critical concentration, the microtubule will polymerize and grow. If the concentration is less than the critical concentration, the length of the microtubule will decrease.


title: Microtubule

text: Dynamic instability refers to the coexistence of assembly and disassembly at the ends of a microtubule. The microtubule can dynamically switch between growing and shrinking phases in this region. Tubulin dimers can bind two molecules of GTP, one of which can be hydrolyzed subsequent to assembly. During polymerization, the tubulin dimers are in the GTP-bound state. The GTP bound to α-tubulin is stable and it plays a structural function in this bound state. However, the GTP bound to β-tubulin may be hydrolyzed to GDP shortly after assembly. The assembly properties of GDP-tubulin are different from those of GTP-tubulin, as GDP-tubulin is more prone to depolymerization. A GDP-bound tubulin subunit at the tip of a microtubule will tend to fall off, although a GDP-bound tubulin in the middle of a microtubule cannot spontaneously pop out of the polymer. Since tubulin adds onto the end of the microtubule in the GTP-bound state, a cap of GTP-bound tubulin is proposed to exist at the tip of the microtubule, protecting it from disassembly. When hydrolysis catches up to the tip of the microtubule, it begins a rapid depolymerization and shrinkage. This switch from growth to shrinking is called a catastrophe. GTP-bound tubulin can begin adding to the tip of the microtubule again, providing a new cap and protecting the microtubule from shrinking. This is referred to as "rescue".


title: Microtubule

text: In 1986, Marc Kirschner and Tim Mitchison proposed that microtubules use their dynamic properties of growth and shrinkage at their plus ends to probe the three dimensional space of the cell. Plus ends that encounter kinetochores or sites of polarity become captured and no longer display growth or shrinkage. In contrast to normal dynamic microtubules, which have a half-life of 5–10 minutes, the captured microtubules can last for hours. This idea is commonly known as the "search and capture" model. Indeed, work since then has largely validated this idea. At the kinetochore, a variety of complexes have been shown to capture microtubule (+)-ends. Moreover, a (+)-end capping activity for interphase microtubules has also been described. This later activity is mediated by formins, the adenomatous polyposis coli protein, and EB1, a protein that tracks along the growing plus ends of microtubules.


title: Microtubule

text: Although most microtubules have a half-life of 5–10 minutes, certain microtubules can remain stable for hours. These stabilized microtubules accumulate post-translational modifications on their tubulin subunits by the action of microtubule-bound enzymes. However, once the microtubule depolymerizes, most of these modifications are rapidly reversed by soluble enzymes. Since most modification reactions are slow while their reverse reactions are rapid, modified tubulin is only detected on long-lived stable microtubules. Most of these modifications occur on the C-terminal region of alpha-tubulin. This region, which is rich in negatively charged glutamate, forms relatively unstructured tails that project out from the microtubule and form contacts with motors. Thus, it is believed that tubulin modifications regulate the interaction of motors with the microtubule. Since these stable modified microtubules are typically oriented towards the site of cell polarity in interphase cells, this subset of modified microtubules provide a specialized route that helps deliver vesicles to these polarized zones. These modifications include:


title: Microtubule

text: A wide variety of drugs are able to bind to tubulin and modify its assembly properties. These drugs can have an effect at intracellular concentrations much lower than that of tubulin. This interference with microtubule dynamics can have the effect of stopping a cell's cell cycle and can lead to programmed cell death or apoptosis. However, there are data to suggest that interference of microtubule dynamics is insufficient to block the cells undergoing mitosis. These studies have demonstrated that suppression of dynamics occurs at concentrations lower than those needed to block mitosis. Suppression of microtubule dynamics by tubulin mutations or by drug treatment have been shown to inhibit cell migration. Both microtubule stabilizers and destabilizers can suppress microtubule dynamics.


title: Microtubule

text: Taxanes (alone or in combination with platinum derivatives (carboplatine) or gemcitabine) are used against breast and gynecological malignancies, squamous-cell carcinomas (head-and-neck cancers, some lung cancers), etc.


title: Microtubule

text: Expression of β3-tubulin has been reported to alter cellular responses to drug-induced suppression of microtubule dynamics. In general the dynamics are normally suppressed by low, subtoxic concentrations of microtubule drugs that also inhibit cell migration. However, incorporating β3-tubulin into microtubules increases the concentration of drug that is needed to suppress dynamics and inhibit cell migration. Thus, tumors that express β3-tubulin are not only resistant to the cytotoxic effects of microtubule targeted drugs, but also to their ability to suppress tumor metastasis. Moreover, expression of β3-tubulin also counteracts the ability of these drugs to inhibit angiogenesis which is normally another important facet of their action.


title: Microtubule

text: Microtubule polymers are extremely sensitive to various environmental effects. Very low levels of free calcium can destabilize microtubules and this prevented early researchers from studying the polymer in vitro. Cold temperatures also cause rapid depolymerization of microtubules. In contrast, heavy water promotes microtubule polymer stability.


title: Microtubule

text: MAPs have been shown to play a crucial role in the regulation of microtubule dynamics "in-vivo". The rates of microtubule polymerization, depolymerization, and catastrophe vary depending on which microtubule-associated proteins (MAPs) are present. The originally identified MAPs from brain tissue can be classified into two groups based on their molecular weight. This first class comprises MAPs with a molecular weight below 55-62 kDa, and are called τ (tau) proteins. "In-vitro", tau proteins have been shown to directly bind microtubules, promote nucleation and prevent disassembly, and to induce the formation of parallel arrays. Additionally, tau proteins have also been shown to stabilize microtubules in axons and have been implicated in Alzheimer's disease. The second class is composed of MAPs with a molecular weight of 200-1000 kDa, of which there are four known types: MAP-1, MAP-2, MAP-3 and MAP-4. MAP-1 proteins consists of a set of three different proteins: A, B and C. The C protein plays an important role in the retrograde transport of vesicles and is also known as cytoplasmic dynein. MAP-2 proteins are located in the dendrites and in the body of neurons, where they bind with other cytoskeletal filaments. The MAP-4 proteins are found in the majority of cells and stabilize microtubules. In addition to MAPs that have a stabilizing effect on microtubule structure, other MAPs can have a destabilizing effect either by cleaving or by inducing depolymerization of microtubules. Three proteins called katanin, spastin, and fidgetin have been observed to regulate the number and length of microtubules via their destabilizing activities. Furthermore, KIAA1211L is predicted to be localized to the microtubules.


title: Microtubule

text: Plus end tracking proteins are MAP proteins which bind to the tips of growing microtubules and play an important role in regulating microtubule dynamics. For example, +TIPs have been observed to participate in the interactions of microtubules with chromosomes during mitosis. The first MAP to be identified as a +TIP was CLIP170 (cytoplasmic linker protein), which has been shown to play a role in microtubule depolymerization rescue events. Additional examples of +TIPs include EB1, EB2, EB3, p150Glued, Dynamitin, Lis1, CLIP115, CLASP1, and CLASP2.


title: Microtubule

text: Microtubules can act as substrates for motor proteins that are involved in important cellular functions such as vesicle trafficking and cell division. Unlike other microtubule-associated proteins, motor proteins utilize the energy from ATP hydrolysis to generate mechanical work that moves the protein along the substrate. The major motor proteins that interact with microtubules are kinesin, which usually moves toward the (+) end of the microtubule, and dynein, which moves toward the (−) end.


title: Microtubule

text: Some viruses (including retroviruses, herpesviruses, parvoviruses, and adenoviruses) that require access to the nucleus to replicate their genomes attach to motor proteins.


title: Microtubule

text: The centrosome is the main MTOC (microtubule organizing center) of the cell during mitosis. Each centrosome is made up of two cylinders called centrioles, oriented at right angles to each other. The centriole is formed from 9 main microtubules, each having two partial microtubules attached to it. Each centriole is approximately 400 nm long and around 200 nm in circumference.


title: Microtubule

text: The centrosome is critical to mitosis as most microtubules involved in the process originate from the centrosome. The minus ends of each microtubule begin at the centrosome, while the plus ends radiate out in all directions. Thus the centrosome is also important in maintaining the polarity of microtubules during mitosis.


title: Microtubule

text: Most cells only have one centrosome for most of their cell cycle, however, right before mitosis, the centrosome duplicates, and the cell contains two centrosomes. Some of the microtubules that radiate from the centrosome grow directly away from the sister centrosome. These microtubules are called astral microtubules. With the help of these astral microtubules the centrosomes move away from each other towards opposite sides of the cell. Once there, other types of microtubules necessary for mitosis, including interpolar microtubules and K-fibers can begin to form.


title: Microtubule

text: A final important note about the centrosomes and microtubules during mitosis is that while the centrosome is the MTOC for the microtubules necessary for mitosis, research has shown that once the microtubules themselves are formed and in the correct place the centrosomes themselves are not needed for mitosis to occur.


title: Microtubule

text: Astral microtubules are a subclass of microtubules which only exist during and around mitosis. They originate from the centrosome, but do not interact with the chromosomes, kinetochores, or with the microtubules originating from the other centrosome. Instead their microtubules radiate towards the cell membrane. Once there they interact with specific motor proteins which create force that pull the microtubules, and thus the entire centrosome towards the cell membrane. As stated above, this helps the centrosomes orient themselves away from each other in the cell. However these astral microtubules do not interact with the mitotic spindle itself. Experiments have shown that without these astral microtubules, the mitotic spindle can form, however its orientation in the cell is not always correct and thus mitosis does not occur as effectively. Another key function of the astral microtubules is to aid in cytokinesis. Astral microtubules interact with motor proteins at the cell membrane to pull the spindle and the entire cell apart once the chromosomes have been replicated.


title: Microtubule

text: Interpolar/Polar microtubules are a class of microtubules which also radiate out from the centrosome during mitosis. These microtubules radiate towards the mitotic spindle, unlike astral microtubules. Interpolar microtubules are both the most abundant and dynamic subclass of microtubules during mitosis. Around 95 percent of microtubules in the mitotic spindle can be characterized as interpolar. Furthermore, the half life of these microtubules is extremely short as it is less than one minute. Interpolar microtubules that do not attach to the kinetochores can aid in chromosome congregation through lateral interaction with the kinetochores.


title: Microtubule

text: K fibers/Kinetochore microtubules are the third important subclass of mitotic microtubules. These microtubules form direct connections with the kinetochores in the mitotic spindle. Each K fiber is composed of 20–40 parallel microtubules, forming a strong tube which is attached at one end to the centrosome and on the other to the kinetochore, located in the center of each chromosome. Since each centrosome has a K fiber connecting to each pair of chromosomes, the chromosomes become tethered in the middle of the mitotic spindle by the K fibers. K fibers have a much longer half life than interpolar microtubules, at between 4 and 8 minutes. During the end of mitoses, the microtubules forming each K fiber begin to disassociate, thus shorting the K fibers. As the K fibers shorten the pair chromosomes are pulled apart right before cytokinesis. Previously, some researchers believed that K fibers form at their minus end originating from the centrosome just like other microtubules, however, new research has pointed to a different mechanism. In this new mechanism, the K fibers are initially stabilized at their plus end by the kinetochores and grow out from there. The minus end of these K fibers eventually connect to an existing Interpolar microtubule and are eventually connected to the centrosome in this way.


title: Microtubule

text: Most of the microtubules that form the mitotic spindle originate from the centrosome. Originally it was thought that all of these microtubules originated from the centrosome via a method called search and capture, described in more detail in a section above, however new research has shown that there are addition means of microtubule nucleation during mitosis. One of the most important of these additional means of microtubule nucleation is the RAN-GTP pathway. RAN-GTP associates with chromatin during mitosis to create a gradient that allows for local nucleation of microtubules near the chromosomes. Furthermore, a second pathway known as the augmin/HAUS complex (some organisms use the more studied augmin complex, while others such as humans use an analogous complex called HAUS) acts an additional means of microtubule nucleation in the mitotic spindle.


title: Microtubule

text: Microtubule plus ends are often localized to particular structures. In polarized interphase cells, microtubules are disproportionately oriented from the MTOC toward the site of polarity, such as the leading edge of migrating fibroblasts. This configuration is thought to help deliver microtubule-bound vesicles from the Golgi to the site of polarity.


title: Microtubule

text: Dynamic instability of microtubules is also required for the migration of most mammalian cells that crawl. Dynamic microtubules regulate the levels of key G-proteins such as RhoA and Rac1, which regulate cell contractility and cell spreading. Dynamic microtubules are also required to trigger focal adhesion disassembly, which is necessary for migration. It has been found that microtubules act as “struts” that counteract the contractile forces that are needed for trailing edge retraction during cell movement. When microtubules in the trailing edge of cell are dynamic, they are able to remodel to allow retraction. When dynamics are suppressed, microtubules cannot remodel and, therefore, oppose the contractile forces. The morphology of cells with suppressed microtubule dynamics indicate that cells can extend the front edge (polarized in the direction of movement), but have difficulty retracting their trailing edge. On the other hand, high drug concentrations, or microtubule mutations that depolymerize the microtubules, can restore cell migration but there is a loss of directionality. It can be concluded that microtubules act both to restrain cell movement and to establish directionality.


title: Microtubule

text: Microtubules have a major structural role in eukaryotic cilia and flagella. Cilia and flagella always extend directly from a MTOC, in this case termed the basal body. The action of the dynein motor proteins on the various microtubule strands that run along a cilium or flagellum allows the organelle to bend and generate force for swimming, moving extracellular material, and other roles. Prokaryotes possess tubulin-like proteins including FtsZ. However, prokaryotic flagella are entirely different in structure from eukaryotic flagella and do not contain microtubule-based structures.


title: Microtubule

text: The cytoskeleton formed by microtubules is essential to the morphogenetic process of an organism's development. For example, a network of polarized microtubules is required within the oocyte of "Drosophila melanogaster" during its embryogenesis in order to establish the axis of the egg. Signals sent between the follicular cells and the oocyte (such as factors similar to epidermal growth factor) cause the reorganization of the microtubules so that their (-) ends are located in the lower part of the oocyte, polarizing the structure and leading to the appearance of an anterior-posterior axis. This involvement in the body's architecture is also seen in mammals.


title: Microtubule

text: Another area where microtubules are essential is the development of the nervous system in higher vertebrates, where tubulin's dynamics and those of the associated proteins (such as the microtubule-associated proteins) are finely controlled during the development of the nervous system.


title: Microtubule

text: The cellular cytoskeleton is a dynamic system that functions on many different levels: In addition to giving the cell a particular form and supporting the transport of vesicles and organelles, it can also influence gene expression. The signal transduction mechanisms involved in this communication are little understood. However, the relationship between the drug-mediated depolymerization of microtubules, and the specific expression of transcription factors has been described, which has provided information on the differential expression of the genes depending on the presence of these factors. This communication between the cytoskeleton and the regulation of the cellular response is also related to the action of growth factors: for example, this relation exists for connective tissue growth factor.


title: Eilean Donan

text: Eilean Donan () is a small tidal island situated at the confluence of three sea lochs (Loch Duich, Loch Long and Loch Alsh) in the western Highlands of Scotland, about from the village of Dornie. It is connected to the mainland by a footbridge that was installed early in the 20th century and is dominated by a picturesque castle that frequently appears in photographs, film and television. The island's original castle was built in the thirteenth century; it became a stronghold of the Clan Mackenzie and their allies, the Clan MacRae. However, in response to the Mackenzies' involvement in the Jacobite rebellions early in the 18th century, government ships destroyed the castle in 1719. The present-day castle is Lieutenant-Colonel John Macrae-Gilstrap's 20th-century reconstruction of the old castle.


title: Eilean Donan

text: Eilean Donan is part of the Kintail National Scenic Area, one of 40 in Scotland. In 2001, the island had a recorded population of just one person, but there were no "usual residents" at the time of the 2011 census.


title: Eilean Donan

text: Eilean Donan, which means simply "island of Donnán", is named after Donnán of Eigg, a Celtic saint who was martyred in 617. Donnán is said to have established a church on the island, though no trace of this remains.


title: Eilean Donan

text: It is possible that an early Christian monastic cell was founded on the island in the 6th or 7th century, and that it was dedicated to Donnán of Eigg, an Irish saint who was martyred on Eigg in April 617. No remains of any Christian buildings survive, though fragments of vitrified stone (stone that has been subjected to very high temperatures) have been discovered, indicating that there was an Iron Age or early medieval fortification on the island.


title: Eilean Donan

text: In the earlier thirteenth century, during the reign of Alexander II (ruled 1214–1249), a large curtain-wall castle (wall of enceinte) was constructed; it enclosed much of the island. At this time, the area around the island was at the boundary of the Norse-Celtic Lordship of the Isles and the Earldom of Ross: Eilean Donan provided a strong defensive position against Norse expeditions. A founding legend has it that the son of a chief of the Mathesons acquired the power to communicate with birds; as a result of this power, and after many adventures overseas, he gained wealth, power, and the respect of Alexander II, who asked him to build the castle to defend his realm.


title: Eilean Donan

text: At a later date, the island became a stronghold of the Mackenzies of Kintail, originally vassals of William I, Earl of Ross. At this early stage, the castle is said to have been garrisoned by Macraes and Maclennans, both clans that were later closely associated with the Mackenzies. Traditional Mackenzie clan histories relate that Earl William sought advantage from the Treaty of Perth of 1266, by which King Magnus VI of Norway ceded the Hebrides to Scotland, and demanded that his kinsman Kenneth Mackenzie return the castle to allow his expansion into the islands. Mackenzie refused, and Earl William led an assault against Eilean Donan that the Mackenzies and their allies repulsed.


title: Eilean Donan

text: The Mackenzie clan histories also claim (with little, if any, supporting contemporary evidence), that Robert the Bruce sheltered at Eilean Donan during the winter of 1306 to 1307; the castle escaped any other involvement in the Wars of Scottish Independence. In 1331 Thomas Randolph, Earl of Moray, sent an officer to Eilean Donan to warn the occupants of his forthcoming visit. In preparation 50 wrongdoers were rounded up and executed, their heads being displayed on the castle walls to Moray's approval. By the middle of the 14th century the Mackenzies are said to have been on the losing side in the ongoing feuding with the Earls of Ross. William III, Earl of Ross granted Kintail to Raghnall Mac Ruaidhrí in 1342. With the assistance of Leod Macgilleandrais, the Earl allegedly apprehended Kenneth Mackenzie, 3rd of Kintail, and had him executed in 1346 at Inverness. Through this period Eilean Donan is said to have been held by Duncan Macaulay for the Mackenzies, against the Earl and his allies. Kenneth's young son Murdo Mackenzie supposedly evaded the Earl's attempts to eliminate him, and on the return of David II from exile Murdo Mackenzie was allegedly confirmed in the lands of Kintail and Eilean Donan by a charter of 1362 (of which, however, no trace survives to the present day). At some point in the earlier 14th century it is thought that the Clan Macrae began to settle in Kintail as a body, having migrated from the Beauly Firth, and there gained the trust of the Mackenzie lairds through possible kinship and an advantageous marriage. The Macraes began to act as Mackenzie's bodyguards, acquiring the soubriquet "Mackenzie's shirt of mail".


title: Eilean Donan

text: James I, determined to pacify the Highlands, journeyed to Inverness in 1427 and invited the principal chiefs to meet him there. Allegedly among them was the young Alexander Mackenzie, 6th Earl of Kintail. James then arrested him, along with the other chiefs, on their arrival. Mackenzie clan histories relate that, although several chiefs were executed or imprisoned, Alexander, due to his youth, was instead sent to Perth to attend school. Alexander's uncles attempted to seize control of Kintail, but the constable Duncan Macaulay continued to hold Eilean Donan on his behalf. Fionnla Dubh mac Gillechriosd, considered by clan historians to be the founder of the Clan Macrae in Kintail, was dispatched to fetch the young laird back. During his lairdship Alexander appears to have supported the monarchy against the MacDonald Lords of the Isles and was allegedly rewarded by another charter of Kintail in 1463. Alexander died in about 1488 at a great age, and was succeeded by Kenneth Mackenzie, 7th of Kintail who won the Battle of Blar Na Pairce against the MacDonalds. Kenneth died a few years later and was succeeded first by his eldest son, then on his death in 1497 by his second son, John of Killin, who was still a minor. His uncle, Hector Roy Mackenzie, attempted to usurp the Mackenzie lands and installed his own constable in Eilean Donan, Malcolm Mac Ian Charrich Macrae. Hector's lawless activities caused the Mackenzies to be branded rebels, and in 1503 the Earl of Huntly offered to deliver Eilean Donan to the king, and to hold it on his behalf. James IV supplied a ship to support the enterprise. Eventually, John compelled his uncle to relinquish his claim, and Hector agreed to hand over Eilean Donan. The constable refused however, and John's supporters laid siege. Malcolm Mac Ian Charrich was eventually persuaded by Hector to relinquish the castle, after which he was dismissed as constable and Christopher Macrae (Gillechriosd Mac Fionnlagh Mhic Rath) was appointed in his place in around 1511. John of Killin obtained a further charter of Kintail and Eilean Donan in 1509.


title: Eilean Donan

text: In 1539, Donald Gorm Macdonald of Sleat ravaged the lands of MacLeod of Dunvegan on Skye and then attacked the Mackenzie lands of Kinlochewe, where Miles (Maolmure), brother of Christopher Macrae, was killed. After a series of retaliatory raids, Donald Gorm learned that Eilean Donan was weakly garrisoned and launched a surprise attack. In fact, only two people were in the castle: the recently appointed constable Iain Dubh Matheson and the warden. Duncan MacGillechriosd of the Clan Macrae, son of the former constable, arrived at the start of the attack and killed several MacDonalds at the postern gate. Arrows launched by the attackers killed Matheson and the warden, but MacGillechriosd managed to hit Donald Gorm with his last arrow, fatally wounding Gorm, and the Macdonalds retreated. Duncan MacGillechriosd expected to be appointed as the new constable but was considered too headstrong: the local clergyman John MacMhurchaidh Dhuibh (John Murchison) was appointed as a compromise between rival Macrae and Maclennan interests. Furious at this treatment, MacGillechriosd left Kintail and joined the service of Lord Lovat, though he eventually returned to settle at Inverinate. Meanwhile, an aggrieved Maclennan apparently shot MacMhurchaidh in the buttocks with an arrow.


title: Eilean Donan

text: MacGillechriosd's son Christopher Macrae became constable of Eilean Donan in turn, and held the castle during yet another clan feud, this time between the Mackenzies and the MacDonalds of Glengarry. Feuding broke out in 1580 and continued for almost 25 years. In around 1602 Eilean Donan was the base for a sea skirmish at the narrows of Kyle Rhea led by Christopher's son Duncan. During the action the MacDonalds were driven on to the Cailleach Rock at the eastern tip of Skye and Angus, son of MacDonald of Glengarry, was killed. Christopher was succeeded as constable by the Rev. Murdoch Murchison, minister of Kintail.


title: Eilean Donan

text: The Rev. Farquhar Macrae, son of Christopher Macrae, was born at the castle in 1580. After attending Edinburgh University and taking holy orders, in 1618 he was appointed constable of the castle and minister of Kintail on the death of Murdoch Murchison. Colin Mackenzie of Kintail was created Earl of Seaforth in 1623. He lived mainly at Chanonry of Ross in Fortrose, but made regular visits to Eilean Donan where the constable was required to entertain him and his retinue of between 300 and 500 retainers, as well as the neighbouring lairds. In 1635 George Mackenzie, 2nd Earl of Seaforth, appointed Farquhar as tutor to his six-year-old son Kenneth, who was subsequently raised at Eilean Donan.


title: Eilean Donan

text: In the civil wars of the mid 17th century, the Earl of Seaforth sided with Charles I. In 1650, after the king's execution, the Parliament of Scotland ordered a garrison to Eilean Donan. The local people did not welcome the garrison. When a party of 30 soldiers came out from the castle to request provisions from the local people, a band of 10 men who opposed their demands met the occupiers. An argument broke out, which led to the garrison men being driven off with several casualties. Shortly thereafter the garrison departed. The following year the Earl's brother, Simon Mackenzie of Lochslin, gathered troops for the royalist cause around Eilean Donan. For reasons unrecorded, he fell out with Farquhar Macrae and demanded his removal from the castle. Farquhar initially resisted, and despite interventions by the young Kenneth, had to be marched out by Lochslin and George Mackenzie (later Earl of Cromartie). He was finally persuaded to leave without violence, stating that he was too old to dwell in the cold castle. Farquhar was thus the last constable to dwell in Eilean Donan until its reconstruction, although he retained the ministry of Kintail until his death in 1662, at the age of 82.


title: Eilean Donan

text: After this time, the castle was briefly occupied by the Earl of Balcarres and his wife, who were in the Highlands in support of the Earl of Glencairn's royalist uprising, although Balcarres later disagreed with Glencairn and departed. In June 1654 General Monck, Oliver Cromwell's military governor in Scotland, marched through Kintail while suppressing the uprising. His troops destroyed much property, and stole 360 of Farquhar Macrae's cattle, though only one man was killed.


title: Eilean Donan

text: In 1689, King James VII of the House of Stuart was declared to have to forfeit the throne, and the crown was offered to William of Orange, in the so-called "Glorious Revolution". The revolution also established Presbyterianism in Scotland, although the Highlands generally remained Roman Catholic and loyal to the Stuarts. A series of Jacobite risings followed, leading to an increased military presence in Scotland as government forces attempted to penetrate and subdue the Highlands. In 1714 while surveying fortifications for the government, the military engineer Lewis Petit made the only surviving drawing of Eilean Donan. The sketch-elevation and carefully drawn plan show a dilapidated castle, largely roofless but for a small building by the entrance.


title: Eilean Donan

text: A major Jacobite uprising took place in 1715. Led by the Earl of Mar, it was an attempt to restore the exiled James Stuart, the "Old Pretender", to the throne. William Mackenzie, 5th Earl of Seaforth, joined the Jacobite army, leading out men of the Clan Mackenzie and Clan Macrae. The Macraes mustered at Eilean Donan, and are said to have danced on the roof of the castle before setting out to the Battle of Sheriffmuir where 58 Macraes were among the Jacobite dead. The battle was indecisive and the rising collapsed soon after.


title: Eilean Donan

text: Following the failure of the rising of 1715, the Jacobites found new support from Spain, now opposing both Britain and France in the War of the Quadruple Alliance. The Duke of Ormonde led the main invasion fleet from Spain, while an advance party of 300 Spanish soldiers under George Keith, 10th Earl Marischal, arrived in Loch Duich in April 1719, and occupied Eilean Donan Castle. The expected uprising of Highlanders did not occur, and the main Spanish invasion force never arrived. At the beginning of May, the Royal Navy sent ships to the area. Early in the morning on Sunday 10 May 1719 , and anchored off Eilean Donan and sent a boat ashore under a flag of truce to negotiate. When the Spanish soldiers in the castle fired at the boat, it was recalled and all three frigates opened fire on the castle for an hour or more. The next day the bombardment continued while a landing party was prepared. In the evening under the cover of an intense cannonade, a detachment went ashore in the ships' boats and captured the castle against little resistance. According to "Worcester"s log, in the castle were "an Irishman, a captain, a Spanish lieutenant, a serjeant, one Scottish rebel and 39 Spanish soldiers, 343 barrels of powder and 52 barrels of musquet shot." The naval force spent the next two days in the castle and landed 27 barrels of gunpowder. The frigates' official logs are curiously worded, perhaps to conceal the reputed fact that the Macraes succeeded in destroying the castle although in naval hands, in order to prevent the English from garrisoning it: at all events, the castle was demolished by the gunpowder exploding. "Flamborough" then took the Spanish prisoners to Edinburgh. The remaining Spanish troops were defeated on 10 June at the Battle of Glen Shiel.


title: Eilean Donan

text: Between 1919 and 1932, the castle was rebuilt by Lt. Col. John MacRae-Gilstrap. The restoration included the construction of an arched bridge to give easier access to the island. Macrae-Gilstrap also established a war memorial dedicated to the men of the MacRae clan who died in the First World War. The memorial is adorned with lines from John McCrae's poem "In Flanders Fields", and is flanked by grey field guns from the war. Eilean Donan was opened to the public in 1955, and has since become a popular attraction: over 314,000 people visited in 2009, making it the third-most-visited castle in Scotland. In 1983 ownership of the castle was transferred to the Conchra Charitable Trust, established by the Macrae family to maintain and restore the castle, and a purpose-built visitor centre was opened on the landward side of the bridge in 1998.


title: Eilean Donan

text: The castle is regularly described as one of the most photographed monuments in Scotland, and is a recognised Scottish icon, frequently appearing on packaging and advertising for shortbread, whisky and other products. Eilean Donan has made several appearances in films, beginning with "Bonnie Prince Charlie" in 1948 and "The Master of Ballantrae" in 1953. The castle was the setting for the 1980 short film Black Angel, filmed to accompany screenings of "The Empire Strikes Back" in cinemas. In 1984, Scottish singer and composer Jesse Rae filmed his music video "Over The Sea" at the location. It featured prominently in "Highlander" (1986) as the home of Clan MacLeod. It was the backdrop to a dance scene in the Bollywood movie "Kuch Kuch Hota Hai" in 1998. In 1999, it served as the Scottish headquarters of MI6 in "The World Is Not Enough". In 2007, Eilean Donan stood in for Fotheringhay Castle in England in "". In the movie "Made of Honor" Eilean Donan can be seen as home of the groom's family. The Tamil song "Kandukondain Kandukondain" from the movie of the same name was filmed in this location.


title: Eilean Donan

text: Eilean Donan Castle went through several phases of development from the earliest fortifications of the 13th century through to its destruction in 1719, and the subsequent reconstruction in the 20th century. The first phase comprised a curtain wall enclosing much of the island with a tower house added in the 14th century. In the 14th or 15th century the outer wall was abandoned and a smaller enclosure built around the tower house. More development within this courtyard took place in the 16th century, as well as the addition of defences on the eastern side. The castle was almost totally destroyed in 1719, after which almost 200 years passed before reconstruction began. Although some archaeological evidence has been recovered from the island, much material was lost during the reconstruction works making it difficult to build a clear picture of the early castle. Very little historical evidence survives. Mapmaker Timothy Pont (c. 1565–1614) left a description:


title: Eilean Donan

text: The only drawing of the castle prior to its destruction was made in 1714 by Lewis Petit (c. 1665–1720), a military engineer with the Board of Ordnance who came to Scotland in 1714 to survey Fort William and other defences in the area. Among the drawings he produced are a plan and elevation of Eilean Donan, which clearly show that the castle was largely derelict by this time, with only a building at the southeast corner being roofed.


title: Eilean Donan

text: In the 13th century, a curtain wall or wall of "enceinte" was constructed around the island, enclosing most of the area above the high tide line. Scant remains of these walls can be traced on the ground, running around the northern end of the island. The eastern and southern segments of this wall are largely obscured by later development, although the enclosure is assumed to have contained an area of around . At the northern point of the wall the foundations of a large tower survive, measuring around and the remains of foundations suggest further towers at the north-east and southwest corners of the enclosure. The enclosure was accessed via a sea-gate in the north-west curtain wall, where a small beach would have allowed boats to be drawn up. Another beach to the southwest may have formed a second access. Archaeological excavations in 2008 and 2009 confirmed the presence of these walls, and also found evidence that metalworking was taking place in the northern part of the castle. A tower house or keep was built against the curtain wall at the high point of the island, probably in the 14th century. The tower measured , with walls thick. The vaulted ground floor was originally divided in two, with a stair in the north wall giving access to the first-floor hall. Above this were probably another two storeys, including a garret. The tower, according to Petit's later drawing, was topped by crowstep gables, and surrounded by a walkway and bartizans (small turrets) at the corners.