Two of the largest mass extinctions on Earth took place at the end of the Permian geologic period. That is the severity that 86% of all animal species were wiped out in the extinction that took place 252 million years ago. The event also marked the beginning of a new era, where the population of terrestrial reptiles exploded rapidly. Until now, scientists believed that the increase in the number of reptiles and their evolution was due to the extinction of their competitors. However, a new study indicates that global warming, rather than mass extinction, is responsible for the explosion in reptile numbers and diversity.
Researchers from the Department of Evolutionary Biology and Biology and the Museum of Comparative Zoology at Harvard University, have revealed that reptile evolution began much earlier than previously thought. .
“We found that the rapid stages of reptile evolution are strongly associated with increasing temperatures. Some groups change very quickly and a few more rapidly, but nearly all reptiles evolve much faster than they did before,” he said. speak Tiago R Simoes postdoctoral fellow. He is also the lead author of the study published in Scientific advance.
The team examined early amniotic membranes that represent the precursors of all modern mammals such as birds, reptiles and their extinct closest relatives. They created a dataset using extensive first-hand data collection of more than 1,000 fossil samples from 125 species of synapses, reptiles and their close relatives about 140 million years before the Great Depression. Permian-Triassic race. They then analyze the data and try to figure out the origins of these species and how fast they evolved.
The new data set is then compared with global temperature data from millions of years ago in the geological record.
The researchers observed that periods of rapid climate change and global warming are associated with rapid anatomical change in most reptiles as they adapt to conditions. environment changes.
The team also looked at changes in the body size of reptiles during this period. They note that the climatic pressure on the body is so great that the maximum body size for reptiles can survive in the tropics during hot periods.