Of gomphotheres, early American Indians, the Lazarus effect and the end of the world

Sometime during 2007, a rancher in the northern Mexican state of Sonora took a visitor to see large bones he had found in an arroyo, or creek bed. The visitor was Guadalupe Sanchez, who works for Mexico’s INAH (Instituto Nacional de Antropología e Historia). It turns out that the bones were not the only item that piqued Guadalupe’s interest; several stone implements were found in association with them. What makes this discovery so very special and highly interesting is the kind of animal the bones belonged to and the nature of the stone tools.

After two years of hushed up investigations, the scientists recently announced that these bones represent two juvenile gomphotheres and the tools belong to the so-called Clovis tradition, a topic which has been the subject of earlier blog entries . The focus here is not on who came first, Clovis or others (that argument has been settled anyway), but rather on the implications of the find of the Gomphothere bones together with Paleoindian tools like those of the Clovis tradition. That is what is drawing the attention of a lot of North American archaeologists these days. In a nutshell, what we have here is described as “the first documentation that there was some sort of human interaction with gomphotheres in North America.”

What in the world is a gomphothere?

WPHubeiPlatybeladonThink of gomphotheres as a type of early elephant, but a strange looking one.
Imagine an elephant-sized animal, with a trunk and tusks pointing straight forward. Then add to that picture a lower jaw with two protruding teeth and voilà, you have a pretty good idea of what our gomphothere looks like.

When were they supposed to have been around?

Considered to have been the most successful and diverse group of Elephants or Proboscideans, these animals thrived during the late Miocene (9 – 8  million years ago) and the Pliocene (5.3 – 1.8 million years ago). The traditional wisdom – up until recently – was that their North American representatives survived the longest in Florida.

Lazarus effect

With dates like these, it would appear then that the jolly pachyderms disappeared about 1.788 million years (give or take a few thousand years) before the earliest humans started walking around in North America. The recent discoveries made at “El fin del Mundo” upended this conventional wisdom. Animals considered long gone by the time of the arrival of the first Americans, now seems to have survived until that point in time. Resurrected from the dead, as one scientist intimated.

The site got its foreboding name because of its very remote location on a ranch in the Rio Sonora watershed. However, being remote is a relative term. Once the news breaks, it is no longer a secret and people will find their way to the site. That is why scientists waited for two years to announce their discovery. This gave them ample time to get a good start on the work that needs to be done.

According to Dr. Vance Holliday, a University of Arizona anthropologist, this is the first time gomphothere fossils were found together with implements made by Clovis people and because of this association, this find has major implications.

Saber-tooth Cat Skull
Creative Commons License photo credit: Ryan Somma

Instead of completely disappearing 1.8 million years ago, some Gomphotheres seem to have survived until relatively recently. Our mental image of early man in the Americas encountering and hunting mammoths and mastodon now has to include Gomphotheres as well. In addition to giant hyenas and sabertooth cats, humans also developed a taste for these creatures.

Are all the gomphotheres gone now?

Even though they survived much longer than originally suggested, gompotheres are no longer with us. However, these lumbering leviathans have been immortalized in a number of outdoor statues, as you can see here, here and here.

Lucy’s Great Mystery: Part 2

Big Cats Everywhere:
Fast Cats,  Semi-Saber Cats, Super-Fast Cats. Not to Mention the Super-Hyenas!

In Part One we learned the frightening facts: Lucy was surrounded by formidable felines. She was too slow to run away and she didn’t have weapons to repel 150 pound leopards or 500 pound  homothere saber-tooths.

Actually – we left some facts out. The predator situation was even worse then what we discussed in the last article.  Lucy’s world had even more kinds of meat-eaters to fear:

Cheetahs
These speedsters have greyhound-like limbs, very long and tipped with nails, not claws. Cheetahs sacrifice climbing ability for acceleration and velocity on the ground. Living cheetahs are leopard size – 120 lbs average. But in Lucy’s time cheetahs were as big as modern lions.

Semi-Saber Tooths – Dinofelis
These felids had the slinky bodies of leopards with an enlarged upper fang. Their saber teeth weren’t as long or as sharp as a Sword Tooth cat but were far larger than in any modern cat.

Sword-Tooth Saber Cats – Smilodonts
These are the chunkiest, most heavily muscled saber-tooths.  In Lucy’s time, smilodonts grew to jaguar size, were heavier than a leopard, but had even more massive forearms and paws. Climbing would be excellent but speed on the ground was slower than a lion’s.  The upper fangs were much longer than those in a Dagger-Tooth homothere.

Lucy would have had to deal with Hyenas too……

The feline situation looked bad enough. The hyenas made it much, much worse.

s-cats-hyenColorRSmallLucy’s time saw the maximum diversity among the African  Hyena clan. Today, the most advanced pack hunter is none other than the Spotted Hyena, Crocuta crocuta. This is a matriarchal hunter. The biggest males don’t rule. Mom does. The alpha female is bigger, smarter and scarier than the males and she makes most of the decisions. Her sisters are next in charge. The Spotted Hyena has a close-knit social structure, and the dominant females are needed to keep order. It works to the kids’ advantage. If  Mom-Hyenas dies, her sisters will help raise the orphans. Hyena clans fan out and go after zebra and antelope, even water-buffalo and young rhinos. The Hyenas run and run and run. They’ve got great stamina.

Super-Crusher Hyena
Lucy had to watch out for Pachycrocuta, what I like to call the Super-Crusher-Hyena. This monster was a close kin of today’s Spotted Hyena but weighed almost as much as a lion – 300 pounds. And the Super-Crusher had jaws with even greater bone-smashing power than in the Spotted Hyena.

A clan of Super-Crusher-Hyenas would have instilled fear even in the biggest Saber-Tooth Cat.

Wolf-Hyena
In Lucy’s time there was a Hyena menace we don’t have today. It was Chasmaporthetes, the Wolf-Hyena. A Wolf-Hyena, seen from a hundred yards away, would look like big-headed Timber Wolf – long-legged, fast, and graceful. Up close, you’d see the Hyena family design. The paws were more compact than a wolf’s and the jaws had meat-cutting teeth were longer and sharper. And there weren’t any big molars in the rear of the mouth. Wolves and coyotes use those rear molars to crunch berries and fruit and other vegetable food. The Wolf-Hyena was more of a pure carnivore.

The Wolf-Hyenas must have been the nightmare of mid-sized hoofed stock, and primates of all sizes, including our Lucy.

Can’t Bite Back.   What defenses Did Lucy Have?

IMG_0876.JPG
Creative Commons License photo credit: rdicker

Chimps and baboons can bite back. They have big canine teeth, especially large in the males. A 90 pound baboon or ape is a nasty close-in fighter. Leopards and hyenas can get terrible wounds from ape and monkey teeth.

But not Lucy.  When australopithecines evolved from apes, the canine teeth got small. Lucy had much poorer dental weapons than what her ape ancestors had.

Final Conclusion:

Let’s roll-play again…..,you’re Lucy or her mate. You weigh 60 to 90 pounds. What do you do when a pack of Wolf Hyenas come over the hill? You can’t out-run them. You might be able to fight off just one Wolf-Hyena, but not a pack of a dozen.

Let’s say by some miracle you get away from the Wolf Hyena clan – then a Giant Cheetah comes at you at 55 mph.

Or you’re resting and a Semi-Saber Tooth Cat attacks. Or a smilodont?

You haven’t a chance….

Old Theories Are Missing Something.

BUT….Lucy and her family did get away, again and again and again. They lived long enough to mate and raise kids and evolve.

How did they do it?

What do you think?

Your Dino Mummy Questions, Answered

Ed. Note: Leonardo has only been on display in Dinosaur Mummy CSI: Cretaceous Science Investigation for a few weeks – but we’ve already gotten a ton of fascinating questions from visitors. In this post, Dr. Bakker  answers them. If you have a question about Leonardo – or anything on exhibit at the Houston Museum of Natural Science – send it to blogadmin@hmns.org and we’ll post the answer here.

Dinosaur Mummy CSI presents scans of Leonardo that show gut contents and even a possible heart. Does Leonardo have lungs preserved?

There are some curious iron concretions revealed by the x-rays here but nothing definite.

Duck-bill dinosaurs do not have hollowed-out bones of the sort we see in birds and raptors and tyrannosaurs. Therefore we don’t expect that they had the very small lungs and big air chambers in the body cavity characteristic of modern birds.

The lungs would be tucked up high in the chest, covered by rib numbers 3,4,5,6 – if the lungs were like those of birds and crocodiles.

The drawings of Leonardo in the exhibit are very colorful – how do you know what colors dinosaurs had on their skin?

…theoretical stripes.

Think “Okapi.” That’s the giraffe-like thing in wet woodlands today.

Dinosaurs had bird-style eyes, so camouflage had to match habitat colors. Dull browns and greys were not good enough to fool an eagle-eyed gorgosaur.

Early Judithian environs had wet forests with big conifer trees and, in the rainy season, thick underbrush. Dry season would bring browns & rust colors.

So……..Mike Berglund (a dinosaur illustrator) has made a testable theory with his partially banded Brachy. Breaking the profile by having the tail a different color would help flummox predators, who would have a more difficult time seeing the whole body and tail shape. The thick verticals would help the beast blend in among the tree trunks.

How can we test color ideas?  More paleo-environmental research. More thinking about fossil pollen, turtles, crocodiles & salamanders….all witnesses to rainfall, groundwater, and floral geometry.

What animals alive today would be most like Leonardo?

Eland
Creative Commons License photo credit: The Anti-ZIM

The Antelope Family – most diverse family of medium-large planteaters on land today. The Antelope Family includes cows and buffalo, gazelles and oryx, funny-faced hartebeest and gnu, cute duikers and stately eland. Muskoxen and sheep and goats. Antelope supply most of the prey for lions, leopards, cheetah and hyenas.

The Duckbill Family is the most diverse, big-ish plant-eaters in the last part of the dinosaurian age, the Late Cretaceous. The Duckbill Family includes our HMNS Edmontosaurus, and the Trombone Dinosaur, Parasaurolophus (kids’ favorite). And the “Good-Mother” Maiasaura, who left us fossil eggs and nests. Leo’s species, Brachylophosaurus, is a duckbill too. Duckbills supplied most of the prey for all the tyrannosaur meateaters, such as Gorgosaurus, Daspletosaurusand the famous Tyrannosaurus rex.

The technical name for the Antelope Family is Family Bovidae, or “bovids” for short.

The technical name for the Duck Bill Family is Family Hadrosauridae, or “hadrosaurs” for short.*

Want to learn more about Leonardo and other dinosaurs?
See how we moved the 6-ton fossil into the museum.
See David Temple repairing and gluing a fossil back together.
Draw a dinosaur with Dr. Bakker.