People have searched for the truth about dinosaurs for centuries. While previous generations may have considered them dragon remnants or fossils placed into the ground by God to test humanity's faith, the real picture has become clearer with each new dinosaur discovery. Research has also illuminated the similarities between dinosaurs and birds - namely, dinosaurs had feathers, among other bird-like traits.
Several of the most important questions, like learning how dinosaurs behaved or what they looked and sounded like, have ambiguous answers at best. Dino researchers have dug up fossils and examined them for generations, but now some question the validity of a few widely believed conclusions. This is happening across the field, with new archaeological discoveries constantly challenging our long-held notions about the ancient, and prehistoric, world.
Along with the discovery of many new dinosaur species, our knowledge about dinosaurs has completely changed. Check out the most shocking facts about these giants.
The Reaper Of Death Is The First New Tyrannosaur Discovered In Canada In 50 Years
Introducing the first new species of tyrannosaur discovered in Canada in 50 years. Meet Thanatotheristes degrootorum, the ‘reaper of death’! Read all about it on our blog: https://t.co/hIQZkxdACk #Thanatotheristes #ReaperOfDeath #RTMPResearch pic.twitter.com/WYNmsMuUFY— Royal Tyrrell Museum of Palaeontology (@RoyalTyrrell) February 10, 2020
Researchers with the University of Calgary and the Royal Tyrrell Museum revealed what they claim to be the first new tyrannosaur species discovered in Canada in 50 years, called the Thanatotheristes degrootorum - which combines the Greek translation for "reaper of death" with the name of the couple who found the fossils, the DeGroots. Jared Voris, a PhD student, found the skull fragments at the Royal Tyrrell Museum, and he concluded they did not match any known species of tyrannosaur, in part because of unique "vertical ridges along the upper jaw line."
The fragments Voris discovered were found near the Bow River by in 2010. Voris' thesis advisor, Darla Zelenitsky, said the new species predates the T. rex by 12 million years, and is therefore the "oldest known tyrannosaur discovered in Canada."
This Thanatotheristes appears to be its own distinct species, rather than an ancestor to the T. rex, and Voris speculates it could have been "8 meters long with an 80-centimeter skull."
The T. Rex Had A Major Growth Spurt As A Teenager
A study released in Science Advances magazine January 1, 2020, alleges the T. rex grew into its full size during adolescence, rendering the existence of the Nanotyrannus, or pygmy tyrannosaur, invalid. Scientists have previously proposed a smaller T. rex lived alongside the giant predators after examining two tyrannosaur skeletons from the Cretaceous period with a similar body structure. The new research, which used osteohistology (the study of bones) to analyze the same samples, studied their growth curves to identify their age, revealing they were "immature individuals 13 to 15 years of age, exhibiting growth rates similar to extant birds and mammals, and that annual growth was dependent on resource abundance."
Paleontologist Steve Brusatte, who reviewed the study, said most scientists are unfamiliar with the growth rates of the T. rex aside from the fact that they "had to grow fast to go from... hatching" out of an egg to approximately 19,000 pounds. Because the two fossils examined by researchers previously thought to be an entirely new species of pygmy dinosaurs are actually adolescent in age, it is likely the T. rex began to grow more rapidly during its teenage years depending on the available food sources.
A Well-Preserved Fossil Provides New Information About The Evolution Between Dinosaurs And Modern Birds
Paleontologist Takuya Imai and colleagues discovered the well-preserved fossil of an Early Cretaceous bird in Japan in 2013. The skeleton, called the Fukuipteryx prima, or F. prima, is the first modern bird recorded outside northeastern China, according to a study published in Nature in November 2019. The study further suggests finding a modern bird skeleton outside China "increases our understanding about the complex morphological evolution in early birds with the presence of particularly primitive features in young individuals," given the animal's assumed age of about 1 year.
Imai told Smithsonian magazine researchers "were not expecting to find such good material from a fossil bird." Similar fossils discovered in China were often squished and incomplete, whereas this one was three-dimensionally preserved. And though the F. prima skeleton is assumed to be nearly 120 million years old, it looks similar to birds that evolved 30 million years earlier in the Jurassic period.
One of the most important features of the F. prima fossil might be its tailbone, also seen seen in birds today and thought to be a marker of birds' evolution from dinosaurs.
Dinosaurs Might Have Been Warm-BloodedPhoto: RJPalmerArt / Wikimedia Commons
For much of paleontological history, many have associated dinosaurs with reptiles - thus, concluding dinos were cold-blooded. However, the evolutionary connections between dinosaurs and birds, along with the revelation most dinosaurs likely had feathers, has led scientists to reevaluate this conclusion.
Since dinosaurs didn't use feathers for flight, it's more likely they were for insulation, which would suggest warm blood. It remains unclear whether all or only some dinosaurs were warm-blooded, but it is possible the trait was universal. In 2020, palentologists published a study that confirmed Ornithischia, Sauropodomorpha, and Theropoda were warm-blooded dinosaurs.
The study, published in Science Advances, tested the temperature of fossilized eggshells to measure the body temperature of certain dinosaurs.