Today, many reptiles have the ability to detach their tail to escape predators. But only one group used the trick during the Permian period. Photo by Aaron LeBlanc
March 6 (UPI) -- The ability to detach a limb is an escape strategy deployed by a number of modern species, but new research suggests the reptile Captorhinus was the first to use the trick.
The small, lizard-like reptiles were ubiquitous during the Earlier Permian period, some 289 million years ago. New analysis of Captorhinus suggests the reptile's evolutionary success could be at least partially explained by its ability to detach its tail to escape the jaws of ancient carnivorous amphibians.
When scientists at the University of Toronto, Mississauga, studied Captorhinus tails, they found a unique pattern of cracks resembling the perforation lines found on a roll of paper towels.
"If a predator grabbed hold of one of these reptiles, the vertebra would break at the crack and the tail would drop off, allowing the captorhinid to escape relatively unharmed," biology professor Robert Reisz said in a news release.
A survey of the fossil record proved the attribute was limited to Captorhinus reptiles and not shared by its reptilian relatives during the Permian period. Scientists also determined the vertebrate cracks developed naturally as the reptiles developed. The perforations sometimes fused in older reptiles, while the tails of young captorhinids broke away easily.
Reisz and his research partners published their analysis this week in the journal Scientific Reports.
While the trait may have allowed Captorhinus to disperse across Pangaea, it couldn't ensure invincibility. The ability died out when Captorhinus went extinct, but tail-detachment re-evolved among lizards some 70 million years ago.