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...