Fascinating Facts About the Tyrannosaurus Rex, Ancestors

SCIENCE PHOTO LIBRARY

Image caption T. rex  lived during the Cretaceous Period

I'm in the process of reading and enjoying an amazing science book called "The Rise and Fall of the Dinosaurs" by paleontologist Steve Brusatte. It's a NY Times Best seller, and that's totally understandable. Once I finish it, I'll review the book, but I wanted to take time and point out a big highlight for the "world's most popular dinosaur."

T-REX ANCESTORS -   I've learned that since I was a kid in the 1970s,paleontologists have been finding and cataloging what can be referred to as the T-Rex family of ancestors. Originally, millions of years before them, T-Rex ancestors were about 150 pounds, standing on 2 feet. As time went on they grew larger and more fierce. During the Jurassic Period, one relative called Allosaurus, was known as the "Butcher dinosaur."You've seen them depicted in the film "Jurassic Park." They grew as long as 33 feet long from head to tip of the tail and were vicious meat-eaters. There were quite a few tyrannosaurs ancestors, like the Yutyrannus,  Qianzhousaurus and Chilantisaurus, to name a few. The T-Rex's ancestor came from China.


WHAT WAS THE CRETACEOUS PERIOD? - Cretaceous Period, in geologic time, the last of the three periods of the Mesozoic Era. The Cretaceous began 145.0 million years ago and ended 66 million years ago; - it was identified by temperature and sea-level changes. It followed the Jurassic Period and was succeeded by the Paleogene Period (the first of the two periods into which the Tertiary Period was divided).

The Rise and Fall of the Dinosaurs

ABOUT THE "KING OF DINOSAURS"- Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), Full grown, they were up to 42 feet long and weighed up to 7 or 8 tons. They typically lived 30 years and were vicious high-consuming meat-eaters. The T-Rex had tiny arms and pretty useless hands. All the T-Rex's power was its head, that spanned about 5 feet from snout to ear! That's as big as an average person!! It had eyes the size of grapefruits, and bony structures around the eyes. Paleontologists have more T-Rex fossils than any other, according to author Steve Brusatte. That's helped them determine T-Rex's had scaly skin with feather-like filaments sticking out of them!  (Of course, later, some dinosaurs developed into birds and those feathers became what they are today).


WHEN WERE T-REX'S PREVALENT ? From 68 to 66 million years ago and they lived in North America. They developed from their ancestors after Pangea (all the current continents previously sandwiched together) broke up. 

WHY DID THEY DISAPPEAR at 66 MILLION YEARS AGO?  That's when the giant asteroid hit the Earth and drastically changed the atmosphere, temperature, etc. The author says all but the flying dinosaurs were driven to extinction by that event and the mammals survived to thrive in cooler temperatures caused by the impact.

Hope you've enjoyed learning these snippets... I will write more, but encourage you
to buy and read the book.