Paleontologists have calculated the total number of tyrannosaurs on the planet
Scientists from the University of California at Berkeley conducted a study on Tyrannosaurus rex. They decided to establish the total number of these creatures that have ever lived on the planet, Science reports.
Paleontological evidence suggests that tyrannosaurs lasted about 2.5 million years. They disappeared along with other dinosaurs 66 million years ago, after a cosmic catastrophe.
Scientists have long believed that it is impossible to reliably estimate the number of extinct species. The authors of the new study applied Damuth's Law: an ecological equation that demonstrates the relationship between body size and population density. According to him, the larger the individual, the lower the population density should be.
Physiology also plays an important role: species with a slow metabolism are able to maintain a high population density. But here scientists ran into difficulty. It is still not known for certain whether the dinosaurs were cold-blooded or warm-blooded.
“We assumed that the physiological data of the tyrannosaurus was somewhere in the middle between a large carnivorous mammal and a large land lizard such as the Komodo dragon,” – said the representatives of the scientific team.
Scientists have found that the average weight of a Tyrannosaurus rex was approximately 5200 kg. Then they made the calculations. According to them, the current population of tyrannosaurs should have been about 20 thousand individuals at any given time. A territory the size of California was supposed to be home to about 3,800 Ti-Rex.
The total number of these creatures for all time has reached 2.5 billion. Meanwhile, the fossil remains of tyrannosaurs are found quite rarely. If the scientists' calculations are correct, the bones of one in 80 million individuals have been found to date.
Previously, scientists found that tyrannosaurs were born relatively small, but then grew very quickly. So, in adolescence, they were already twice as long as a horse.
