Captorhinus: Scientists Discover Ancient Reptile That Might Have Been First To Detach Its Tail

Ghedoghedo (Own work)Wikimedia Commons/Cropped and Resized

It’s not uncommon for modern lizards to detach their tails in order to protect themselves from predators. And it appears that this self-defense technique was in place close to 300 millions of years ago, as a new study suggests that one ancient reptile species had this ability, making it likely that Captorhinus was the first to come with a detachable tail.

In a new study published earlier this week in the journal Scientific Reports, researchers from the University of Toronto in Mississauga detailed their analysis of 70 chunks from Captorhinus‘ tail bones, and explained how it was able to use its then-unique abilities to throw off predators. This was inferred by the cracks found in the reptile’s tail, which it apparently detached so that it could run away and avoid other animals as they gave chase. As described by Newsweek, this tail-removing ability is best compared to the ease in which people can get a paper towel from a roll due to the perforations.

Compared to the dinosaurs that would arrive several millions of years later, Captorhinus was a very small example of an ancient reptile, weighing in at only four and a half pounds, according to National Geographic. The animal lived about 289 million years ago, during the Permian period, and thanks to its tail-removing feature, was able to spread throughout the ancient supercontinent of Pangaea. A news release from the University of Toronto also noted that the feature was unique among Permian period reptiles, and helped make Captorhinus the most common reptile of its time.


“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,” read a statement from University of Toronto biology professor Robert Reisz, lead author on the new study.

In addition to the above findings, the researchers discovered that it was mostly younger examples of the species that were able to detach their tails; the team opined that this “makes sense,” as younger animals are typically at greater risk from predators than their adult counterparts. Although there were still cracks found in the tail fossils of adults of the species, the researchers noticed that these cracks appeared “fused up” in some cases, further suggesting that the reptiles didn’t need to detach their tail as often as before once they had matured.

Despite thriving during the Permian period, Captorhinus ultimately wasn’t able to make it to the age of dinosaurs. At the time of its extinction, that made it the last reptile to be able to detach its tail, though as National Geographic stressed, modern reptiles often have such a feature in place, as it resurfaced about 70 million years ago.