The thylacine is used as an example of evolutionary convergence, with a dog-like body, non-retractable claws and a species name translating as “dog head”.
However, its elbow has a larger range of motion than pursuit carnivores such as wolves. Dr Borja Figuerido of Brown University, Rhode Island, suggests in Biology Letters that this indicates that thylacines hunted largely by ambushing their prey.
“The price paid by pursuit predators for limbs adapted for speed and locomotor efficiency is the restriction of the range of joint motion, and hence the loss of the ability to supinate the forearm, which is essential for grappling with prey,” wrote Figuerido.
The thylacine, on the other hand, had a capacity for elbow motion that placed it well in the range of ambush predators.
The finding casts doubt on the notion that the thylacine’s extinction from the mainland was caused by the arrival of the dingo moving into its environmental niche. Nevertheless, Figuerido acknowledges that the effect of dingoes on prey numbers may have contributed to the thylacine’s mainland disappearance.
