animal navigation animal navigation ability animals find way accurately maps instruments birds arctic insects monarch butterfly fish salmon regularly migrate thousands miles breeding grounds species navigate effectively shorter distances dead navigating known position information speed direction suggested possible mechanism 20th century showed honey bees navigate sun pattern blue sky earth magnetic field rely sun possible showed similarly use range navigational cues including sun earth magnetic field vision demonstrated species small orient fly home speed released far home provided sun stars visible species animal integrate cues different types orient navigate effectively insects birds able combine learned landmarks direction earth magnetic field sky identify navigate internal maps formed vision senses including ability wild animals navigate adversely affected products human activity example evidence interfere bee navigation lights harm turtle navigation early research wrote letter nature magazine arguing animals including man ability navigate dead magnetic compass sense ability navigate stars present regard question means animals find way home long distance striking account relation man found english translation expedition north siberia describes wonderful manner natives kept true course particular spot whilst passing long distance ice changes direction guide heavens frozen sea states quote memory years standing experienced surveyor compass failed easily effected suppose possessed special sense absent bear mind compass north star sign guide man particular spot intricate country ice straight course inevitable allowed sort dead kept men able greater degree natives siberia apparently wonderful extent probably unconscious manner effected chiefly doubt partly sense muscular movement manner man eyes blinded proceed men better short distance nearly straight line turn right angles manner sense direction suddenly old persons feeling strong distress know experienced persons suddenly found proceeding wholly unexpected wrong direction leads suspicion brain specialised function direction later replied darwin writing nature description murphy believed animals carried dead called navigation ball freely suspended roof railway carriage receive shock sufficient carriage set motion magnitude direction shock depend magnitude direction force carriage begins change motion carriage shock corresponding magnitude direction ball possible mechanism hoped machine constructed registering magnitude direction time occurred data position carriage calculated moment studied european honey bee demonstrating bees recognize desired compass direction different ways sun pattern blue sky earth magnetic field showed sun preferred main compass mechanisms cloudy skies inside dark studied showing able navigate earth magnetic field sun visual cues studied bats demonstrating possible bats mechanism detect track prey navigate world studies birds books pioneered science bird migration year study living remote island small longest bird kilometres return exact nesting year year behaviour led question mechanisms began book animal navigation words animals find way apparently country forests seas course visible compass chart mechanisms proposed animal navigation evidence number investigators forced simplest example animals navigate dark cloudy night landmarks cues like sun moon stars visible major mechanisms known described turn remembered landmarks animals including mammals birds insects bees capable learning landmarks environment navigation orientation sun animals navigate cues position sun sun moves sky navigation means requires internal clock animals depend clock maintain rhythm animals use sun compass orientation fish birds sea turtles butterflies bees reptiles ants taken beach easily find way sea shown simply moving downhill sight sound sea group day night cycle artificial lighting timing gradually changed hours phase natural cycle placed beach natural sunlight moved away sea beach experiment implied use sun internal clock determine heading learnt actual direction sea particular beach experiments showed released clear sky far nests oriented flew correct direction sky overcast time release flew circles monarch butterflies use sun compass guide southwesterly autumn migration canada mexico orientation night sky pioneering experiment showed placed showing night sky oriented south sky slowly rotated birds maintained orientation respect displayed stars observes navigate stars birds need built ability read patterns stars navigate requires accurate time day clock african beetle shown navigate patterns making animal known use orientation shown beetles navigate way clusters bright stars visible making beetles insects known orient galaxy orientation light animals notably insects honey bee sensitive light honey bees use light overcast days estimate position sun sky relative compass direction intend travel work established bees accurately identify direction range food source typically patch bearing flowers worker bee returns signals workers range direction relative sun food source means dance observing bees able locate food flying implied distance given direction questioned necessarily simply stimulated search food bees certainly able remember location food navigate accurately weather sunny case navigation sun remembered visual landmarks largely overcast light animals including mammals blind mole rats birds sensitive earth magnetic field use magnetic field information navigational cues pioneering researcher showed time shifted orient correctly clear sunny day overcast day suggesting birds prefer rely direction sun switch magnetic field cue sun visible confirmed experiments orient correctly overcast day magnetic field disrupted navigation suggested possible mechanism mosaic model argues build remember mental map area recognizing local gradient model argues steady large scale gradient remains stable long periods different directions locate dimensions clear stable exist find evidence unable detect able orient navigate normal important navigation clear cues cues important salmon known return exact river hatched reports experimental evidence fish accurately tell difference waters different rivers salmon use magnetic sense navigate reach river use identify river close range senses considered senses contribute animal navigation marine animals seals capable reception enabling track catch prey fish sensing disturbances passage leaves water marine mammals species bat capable use detecting prey orientation sensing environment path integration dead animals usually known path integration means putting cues different sensory sources body reference visual external landmarks estimate position relative known starting point continuously travelling path necessarily straight seen problem geometry task starting point adding leg journey point darwin quoted path integration shown important navigation animals including ants birds vision use remembered landmarks available animals navigating cloudy night open ocean relatively areas sandy path integration rely cues body studies desert demonstrate effective path integration determine directional heading light sun position distance monitoring leg movement optical flow path integration mammals makes use organs detect dimensions motor motor system tells rest brain movements commanded flow visual system signals fast visual world moves past eyes information senses integrated certain animals brain linear angular motion relative position space states carefully controlled experiments demonstrated path integration mammals consequence integrating internal cues signals motor copy effects human activity ability bees navigate bees exposed low levels likely return colony extent sufficient compromise colony survival light pollution attracts animals follow light example sea turtles follow bright light particularly bluish light altering navigation disrupted navigation easily observed bright lamps summer nights insects gather lamps high instead navigating naturally
Animal navigation