Tag Archives: scavenger

It’s settled – Tyrannosaurus Rex hunted for live prey

The king of all predators, the godfather of his time, la creme de la creme – Tyrannosaurus Rex (T. Rex) was the ultimate predator… or was he? When Jurassic Park came out, even though the cinema crowd went wild as T. Rex smashed and ate velociraptors (and the occasional human), at the time, there was no compelling proof that the dinosaur actually hunted – some teams actually claimed that he was a scavenger.

trex

In 2011, a team from the Zoological Society of London reaffirmed T. Rex as the mean green killing machine we all know:

“It is effectively impossible for Tyrannosaurus rex to have fed solely or almost completely on carcasses of dead animals. T. rex lived in an ecosystem with a large number of smaller-bodied carnivorous dinosaur species and it couldn’t have relied on carcasses for its diet,” said Sam Turvey, a co-author of the study published in Proceedings of the Royal Society B.

It seemed obvious that T. Rex was a hunter. But few doubts still remained. Now, another study seems to pin the final nail in the scavenger theory.

The researchers found a T. rex tooth stuck between vertebrae in the tail of a herbivorous duck-billed hadrosaur. The fossils came from a famous area in South Dakota – the Hell Creek Formation.

This CT scan of a duck-billed hadrosaur's vertebra shows an embedded T. rex tooth crown with bone tissue that regrew around it.

This CT scan of a duck-billed hadrosaur’s vertebra shows an embedded T. rex tooth crown with bone tissue that regrew around it.

The finding is very significant because the T. rex tooth is surrounded by bone that clearly grew after the tooth became lodged there. This could only happen if the predator bit the herbivore’s tail, lost its tooth there, as well as the prey.

“It’s a smoking gun. We finally have Tyrannosaurus rex caught in the act,” says Bruce Rothschild, a palaeopathologist at the University of Kansas in Lawrence and a co-author of the paper. “We’ve seen plenty of re-healed bite marks attributed to Tyrannosaurus rex, but it’s hard to confirm identity with those,” says Thomas Holtz, a vertebrate palaeontologist from the University of Maryland in College Park. “Actually having the broken tooth makes it easy to determine who was doing the hunting here,”

But even with this, some are hard to convince.

“I’ve long argued that Tyrannosaurus rex was an opportunist like a hyena, sometimes hunting and sometimes scavenging. This provides no evidence to the contrary,” says Jack Horner, a palaeontologist at the Museum of the Rockies in Bozeman, Montana, who served as scientific adviser on the Jurassic Park films.

But even as a few argue that he wasn’t a pure predator, and more argue that he in fact was, even a larger group is just fed up by this debate.

“Great galloping lizards!” exclaims John Hutchinson, an evolutionary physiologist at the Royal Veterinary College in London. “It is so frustrating to see provocative half-baked ideas about celebrity species like Tyrannosaurus rex drawing the public’s attention when there is so much more interesting palaeontology to be talking about.”

Via Nature

T-Rex’s reputation is restored – he was a hunter

The fascination with T. Rex goes back a really long time, and whether you’re a world class paleontologist, or some average Joe who loved Jurassic Park, T. Rex was definitely on your mind at some point. The biggest and most fierce hunter there was… or was he ? Scientists have been debating his diet for half a century, with one side claiming it fed by scavenging, while the other one is defending the dinosaur as a fearsome hunter.

Tyrannosaurus Rex – a rightful king?

Recently, the debate seemed to shift to one direction, as more and more arguments seemed to disapprove the fact that T. Rex was a scavenger. His honour is also at stake, but mostly it’s all about understanding the eating habits of probably the most known dinosaur ever to walk the Earth. In the scavenger camp, one of the members was Jack Horner at the Museum of the Rockies in Montana, who served as technical adviser on the Jurassic Park movies. He claims that despite his razor sharp teeth, huge head and muscular build, he would have been a dreadful hunter, due to the pathetic forearms and apparently poor eyesight.

But latest studies, including the one performed recently by the Zoological Society of London reaffirm T. Rex as the mean green killing machine most people know him as.

“It is effectively impossible for Tyrannosaurus rex to have fed solely or almost completely on carcasses of dead animals. T. rex lived in an ecosystem with a large number of smaller-bodied carnivorous dinosaur species and it couldn’t have relied on carcasses for its diet,” said Sam Turvey, a co-author of the study published in Proceedings of the Royal Society B.

Instead of focusing just on the dinosaur, they tried to put together a picture of T. Rex’s ecosystem, and found out that through sheer force of numbers, other dinosaurs were 14 to 60 times more likely to encounter carcasses of dead dinosaurs than an adult T. Rex; even if the big dinosaur were to encounter a carcass, there would probably be little left for it to eat.

“If T. rex chanced upon a carcass it would have been able to keep others away and eat it, but it wouldn’t have been able to find carcasses regularly enough to survive, given competition from these other species,” Turvey added.