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Paleontologists Stunning Conclusion: 2.5 Billion T. Rexes Roamed North America Over the Cretaceous Period TOPICS:DinosaursEvolutionPaleontologyPopularTyrannosaurus RexUC BerkeleyBy University of California - Berkeley April 15, 2021Analysis of what’s known about the dinosaur leads to conclusion there were 2.5 billion over time.How many Tyrannosaurus rexes roamed North America during the Cretaceous period?That’s a question Charles Marshall pestered his paleontologist colleagues with for years until he finally teamed up with his students to find an answer.What the team found, to be published this week in the journal Science, is that about 20,000 adult T. rexes probably lived at any one time, give or...

The newly named tyrannosauroid dinosaur, Suskityrannus hazelae, stood around 3 feet tall at the hip and was about 9 feet long, according to Virginia Tech. “My discovery of a partial skeleton of Suskityrannus put me onto a scientific journey that has framed my career,” said Nesbitt, the lead author of the study in the journal “Nature Ecology and Evolution.” But for about two decades, scientists weren’t certain what it was, until other small cousins of T. rex were discovered. “The small group of tyrannosauroid dinosaurs would give rise to some of the biggest predators that we’ve ever seen,” Nesbitt said....

Tyrannosaurus rex: Scavenger or Predator? by Tim Clarey, Ph.D. * Tyrannosaurus rex looms in recent history as likely the most famous dinosaur that ever lived. The Jurassic Park movies pumped new life into its image as a savage predator. But how much of this is Hollywood hype and how much reflects science? Looking at the numbers, an adult T. rex weighed in at over five tons. If it were endothermic (i.e., warm-blooded), it would need to eat the equivalent of a full-grown, three-ton hadrosaur each week. If it were ectothermic (i.e., cold-blooded), it would only require a fifth to a...

Youth was easy for big predatory dinosaurs – but adulthood and old age much harder to survive, a mass graveyard of tyrannosaur fossils suggests. This first study of dinosaur population distributions shows that most juvenile tyrannosaurs survived to reach sexual maturity, but then their death rate increased sharply in adulthood. This life-pattern is similar to those of long-lived birds and mammals. *SNIP Biologists study population distributions of modern animals by counting individuals and keeping track of deaths. This is not possible for extinct creatures, and fossilised remains are also scant for many dinosaurs. But Erickson turned to the tyrannosaur family...

In the 1993 movie Jurassic Park, one human character tells another that a Tyrannosaurus rex can't see them if they don't move, even though the beast is right in front of them. Now, a scientist reports that T. rex had some of the best vision in animal history. This sensory prowess strengthens arguments for T. rex's role as predator instead of scavenger. Scientists had some evidence from measurements of T. rex skulls that the animal could see well. Recently, Kent A. Stevens of the University of Oregon in Eugene went further. He used facial models of seven types of dinosaurs...

WASHINGTON — For more than a century, the study of dinosaurs has been limited to fossilized bones. Now, researchers have recovered 70-million-year-old soft tissue, including what may be blood vessels and cells, from a Tyrannosaurus rex. If scientists can isolate proteins from the material, they may be able to learn new details of how dinosaurs lived, said lead researcher Mary Higby Schweitzer of North Carolina State University. "We're doing a lot of stuff in the lab right now that looks promising,'' she said in a telephone interview. But, she said, she does not know yet if scientists will be able...

<p>"But now a 70-million-year-old Tyrannosaurus rex discovered in Montana has apparently yielded the improbable, scientists reported yesterday: soft tissues, including blood vessels and possibly cells lining them, that "retain some of their original flexibility, elasticity and resilience."</p> <p>Moreover, an examination with a scanning electron microscope showed the dinosaur's blood vessels to be "virtually indistinguishable" from those recovered from ostrich bones. The ostrich is today's largest bird, and many paleontologists think birds are living descendants of some dinosaurs."</p>

Papers have been flapping with new headlines about the latest in a long line of alleged dinosaur ancestors of birds. This one is claimed to be a sensational dinosaur with feathers on its hind legs, thus four ‘wings’.1 This was named Microraptor gui—the name is derived from words meaning ‘little plunderer of Gu’ after the paleontologist Gu Zhiwei. Like so many of the alleged feathered dinosaurs, it comes from Liaoning province of northeastern China. It was about 3 feet (1 meter) long from its head to the tip of its long tail, but its body was only about the size...