A New “Lady” in Town, Part II: Priscilla the loner mastodon was meatier than a mammoth, but he was no meathead

And now, back to our Priscilla.

Priscilla the Mastodon

The American mastodon starred in the opening chapters of American science. Thomas Jefferson got some mastodon bones from Kentucky and put them on display in the White House in the 1790s.

In the 1790s Wistar, one of the nation's great medical anatomists, had become fascinated with the ancient bones of exotic species. At the White House, to which he had been invited by President Thomas Jefferson, Wistar examined the bones of a mastodon that George Rogers Clark unearthed in 1807 at Bone Lick, Kentucky. Wistar then wrote the detailed description pictured next to the bone.

Jefferson was sure that wild mastodons still roamed the unexplored land west of the Mississippi, so he instructed explorers Lewis and Clark to find them. By 1860, dozens of skeletons adorned the halls of museums in North America.

Despite their early fame, American mastodons were overshadowed by mammoths. The average bull Columbian mammoth is noticeably taller. The big fossil halls in New York City, Denver and Los Angeles exhibit both, and there’s no doubt who is the heavyweight.

However, during the Ice Age in Florida, Nature produced some extremes. Priscilla was an old, old bull. He had arthritis in his lower back, and some stiffness in the shoulders. But he wasn’t crippled by any means — despite his great age, he shows healthy leg joints. Elephant bulls today continue growing throughout their lives, if their diet is healthy. Priscilla must have chosen his food well over 50 or 60 years. He grew an extraordinarily wide pelvis and set of ribs — he’s well over six feet, side to side, across the hips. His leg bone shafts match the length in most mammoths, but Priscilla’s legs are far thicker and stronger.

Priscilla was buff. We know that because fossil leg bones show the size and strength of muscles during life. Where powerful muscles attached to the bone, the surface is roughened and ridged. Priscilla’s limbs are outstanding in the development of muscle-attachment marks. So he was not only unbelievably wide, he was Schwartzeneggerian in muscularity.

Priscilla the Mastodon

Priscilla is especially massive in the forequarters and the low shoulders make him look like a proboscidean fullback, ready to make a first down in a short yardage situation. The gigantic power in the elbow joint means he could thrust forward with the acceleration of a out-sized rhino. Once he decided to charge, few objects — plants or animals — could stand in his way. If he wanted a path through the woods, he just smashed the trees down.

Priscilla was buried in a Florida stream about 13,000 years ago, a time when human hunters were skulking through the continent. Did Priscilla meet a human? No spear point was found with him and his bones show no evidence of being cut by stone knives after death. Spear points and butcher-cuts document human hunting of mammoth at many sites across the continent. But only a few mastodon skeletons carry the CSI evidence of human attack.

What do we know about Priscilla’s social life? Was he solitary? There are hints that mammoths traveled in herds led by wise old matriarchs, just as modern day elephants do. Cave paintings in Europe show many mammoths together. In North America, several mammoth digs came up with multiple specimens, including moms and calves — maybe the result of a herd dying together. The Waco Mammoth museum displays such a site.

More evidence for matriarchal mammoths comes from where male mammoths are buried. At Hot Springs Mammoth trap in South Dakota, nearly 50 Columbian mammoths sank into loose sand and died over a long span of time. All were male, mostly young adults.

In the modern elephant herd structure, matriarchs drive the males away after the boys go through puberty. Then the young fellows live alone or in bachelor groups. And like bachelors of many species, the male elephants are inquisitive, aggressive and do really stupid things. Like plunge into soft sand without thinking.

Mastodons seem to be way different. Multiple skeletons are rarely piled up in single sites. Bachelor groups are unknown. Most mastodon sites contain just a single skeleton. And so, perhaps we should envision Priscilla as being unsociable, like the giant forest-living rhinos today in Asia and Africa. With a hair-trigger temper and distrust of everyone, the mastodon bull might well have been just too frightening for human hunters to pursue.

I imagine being an Ice Age hunter standing at the edge of a Florida forest. I can hear deep tummy rumbles and coarse trumpeting 200 yards in. I can see birch trees flattened. Tree trunks a yard wide splintered.

“Are we going in?” My companion asks.

“Are we nuts?” I reply.

Don’t answer that.

A New “Lady” in Town, Part I: Why Priscilla the mastodon isn’t a mammoth at all

“It’s the biggest gosh darn mastodon I ever saw! Wowzah!

Yes, that’s a direct quote.

It wouldn’t be a lie to say it’s hard to surprise our esteemed Dr. Bob Bakker, Curator of Paleontology. (That would be me.) But Priscilla did it.

“It’s H-U-G-E ! You could fit a Diplodocus torso inside this rib cage!”

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I was standing under the capacious hips of our new cast Mammut americanum, better known as “the American Mastodon.” The stupendous backbone and legs were being hoisted up on cables so the Black Hills Institute staff could attach the head. Mind you, we at HMNS are no strangers to the mastodon — we’ve had a fine cast of a bull on display in our old hall. Big, formidable.

But Priscilla is way off the scale — in life, twice as heavy as the average bull Mammut. And far more massive than our new Columbian mammoth who will co-star in the new fossil hall.

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I’m getting ahead of myself, so let’s back up for a second.

What exactly is a mastodon? And how’s it different from a mammoth (because it is, you know)?


North America has two fossil mammoths. The famous woolly mammoth, star of the Ice Age movies, lived in the far north, close to the glaciers. The Columbian mammoths were taller and even heavier and stayed further south, away from the frigid realms. For two million years, Columbian mammoth clans and mastodon were neighbors. They’re found together in many Texas Ice Age sites, at the famous La Brea Tar Pits, and scores of other excavations from Florida to Oregon as well.

Sure, from a distance, the mammoth and mastodon do seem similar. Both have big bodies, bulgy bellies, straight legs, short necks and compact skulls with a hole in the forehead where the long trunk attached in life. The tusks are long and curved and there is just one well developed pair in the upper jaw. (Mastodons might have tiny tusk vestiges in the lower jaw too.)

When they were alive, both would run with long strides with their weight supported by wide five-toed paws embedded in thick, cushiony pads. Both would move their limbs in that unusual gait employed by modern elephants — right fore and hind swung back together and forward together, while the left fore and hind went forward when the right limbs went back. And vice versa.


But the mastodon clan and the mammoth clan separated some 25 million years ago. The short skulls, long upper tusks and well-developed trunks are mostly evolved in parallel from an ancestor who had long jaws and four long tusks — two in the upper jaw, two in the lower.

All mammoths really are genuine elephants, very close kin of the Asian elephant you see in zoos — that’s why scientists trying to clone a woolly mammoth from frozen specimens in Siberia hope to use the egg from a female Asian elephant.

All mammoths have elephant-style molars. Each tooth crown is a gigantic vegetable processor, with many vertical plates of enamel set in a mass of dentine and cement. (Clever system.) As the uppers and lowers grind against each other, the cement and dentine wear away faster than the enamel. So, the enamel ridges stick up a bit more, guaranteeing that the tooth still has multi-edged cutting/chopping/mincing action until the tooth is totally worn out.

Now look into the mouth of our American mastodon and you’ll see the outstanding difference. The teeth are much smaller and simpler and have nothing like the food-processing power of a mammoth’s grinder. Each mastodon tooth is like a human molar or a pig molar. There are four or six main cusps in two rows, one inside and one outside. The total volume of one molar is one-twentieth that of a mammoth of the same body size. And when the enamel outer covering wore away in a mastodon, there were no vertical ridges of enamel left to cut and chop.

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Clearly mastodons had to be more persnickety about their food choices than did the mammoths. Fossil stomach contents show that mammoths had an elephant-like diet: rushes, sedges, grass, branches, clumps of broad-leafed tree leaves. Stomach remnants and food bits caught between molars tell us that mastodons sought out soft bark from birch trees, soft branches, soft leaves, fallen fruit and nuts with just a wee bit of grass as a garnish.

After analyzing the dental differences, you’d predict that mastodons stayed in wetter, more wooded environments, rich in bushes and young trees. Mammoths would, on the contrary, penetrate far across the open meadows, grasslands and even deserts.

The census of fossil sites confirm your prediction.

Mastodon remains are abundant in bogs and swamps and sandbars from rivers flowing though forests. Mammoths, on the other hand, left many skeletons in sand dunes and rivers that flowed through open terrain. Occasionally both do occur in one spot, but usually one or the other dominates.

Stay tuned for Part II, where you’ll get to know Priscilla like you’ve never known a mastodon before.



(You can’t make this stuff up.)

Priscilla in Black Hills


Says Associate Curator of Paleontology David Temple:



Priscilla in Black Hills



