HOW MANY T. REX EVER LIVED? BILLIONS
Counting the iconic carnivores that roamed the Earth. Palaeontologists have crunched the numbers to estimate just how many Tyrannosaurus rex lived and died – and the answer could be in the billions.
This new study, published in Science, estimates that about 20,000 adult T. rex lived at any one time and that the species persisted for about 127,000 generations – meaning 2.5 billion walked the Earth in total.
Lead author of the study, Charles Marshall, says the project started off as a “lark”.
“When I hold a fossil in my hand, I can’t help wondering at the improbability that this very beast was alive millions of years ago, and here I am holding part of its skeleton,” says Marshall, a professor at UC Berkeley, US.
Large uncertainties about population at any given time mean that the real number could be as low as 140 million or as high as 42 billion.
Though these calculations will undoubtedly be challenged by other palaeontologists, the framework for estimating extinct populations could be useful to apply to other species.