Dan Pelle/The Spokesman-Review/AP
A child looks through a Tyrannosaurus rex interactive exhibit, as his younger sister peeks through the head of a Triceratops at the Mobius Science Center in downtown Spokane, Wash., last month.

Did T. rex play with its food?

Patterns of bite marks on bones chomped on by tyrannosaurids are consistent with play behavior exhibited by modern animals, says one paleontologist.

Tyrannosaurus rex, the seven-ton, dagger-toothed, Cretaceous-period killing machine, may have had a playful side, according to a University of Kansas paleontologist.

Professor Bruce Rothschild says that the 40-foot predator engaged in play, or at least exhibited behavior consistent with play seen in modern-day animals.

But T. rex didn't fetch sticks or chase Frisbees. Rothschild says that, like a huge kitten, T. rex played with its food – in this case, the carcasses of six-ton ceratopsians, a group of dinosaurs that includes the Triceratops. These terrifying, yet strangely adorable, findings come from Rothschild's examination of fossilized bones found both at feeding sites and in isolation.

Rothschild analyzed a previous study and examined fossils from museum collections, including one at the University of Kansas in Lawrence.

The bones from feeding sites came from the parts of the animals that would have had the most meat. They had the type of tooth marks and broken bones consistent with T. rex's feeding habits. And this dinosaur had a legendary bite: Able to chomp down with nearly 13,000 lbs. of pressure and tear off 500 lbs. of meat with one snap, T. rex had the strongest bite of any land animal.

But the bones found in other, more isolated areas were different. They were from body parts that deliver less nutrition, many of them from ball-shaped bones at the back of the skull called occipital condyles. The bite marks themselves are different as well.

In a paper published in the journal Ethics, Ecology & Evolution Rothschild writes that the pattern of bite marks on these isolated bones are “incompatible with feeding activities, but it characteristic of that found with play by contemporary animals.”

By learning more about how prehistoric animals lived, scientists hope to discover more about how modern animals evolved and how they interact with today's environment.

“Deductive reasoning leads to an alternative explanation,” Rothschild wrote, “Tyrannosaurids played with those bones.”

But not everyone accepts the playful dinosaur hypothesis.

“It's not inconceivable,” says Thomas Holtz, University of Maryland paleontologist, “and in fact we do know that the old warm-blooded biases of biologists who thought birds and mammals played but reptiles didn't is just plain wrong.”

“So there's no reason not to think that any given dinosaur, including T. rex might have played.”

“That said, to then say these  … tooth marks necessarily point to or even suggest play behavior rather than anything else is fairly difficult.”

In a phone interview, Dr. Holtz said there are other reasonable explanations for the bite marks.

“It depends on how much of the animal they were eating. Other people have suggested that these tooth marks were not on the parts of the body the T. rex was eating, but as the result of the T. rex. dismembering the animal to get to the tastier parts.”

You've read  of  free articles. Subscribe to continue.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to Did T. rex play with its food?
Read this article in
QR Code to Subscription page
Start your subscription today