Tail of defence: an almost complete tail skeleton of Plateosaurus (Sauropodomorpha, Late Triassic) reveals possible defence strategies.

Abstract

In 2015, a partial skeleton of the Late Triassic dinosaur Plateosaurus trossingensis was excavated from Frick, Switzerland, and subsequently mounted at the Natural History Museum of Vienna in 2021. This specimen includes an almost complete series of tail vertebrae, with a well-preserved, articulated whip-like distal end. The preserved tail structure provides valuable insights into the morphological implications of tail function and its potential role in the behaviour of Plateosaurus. Using the caudal vertebrae, we reconstructed and analysed the potential tail-lashing capabilities of Plateosaurus, comparing its biomechanics with those of other fossil and extant long-tailed reptilian taxa, including the extinct sauropod Diplodocus, the extant Asian water monitor (Varanus salvator), and the green iguana (Iguana iguana). Our results indicate that the tail of P. trossingensis was highly flexible, with an estimated kinetic energy output ranging between 0.537 and 1.616 kJ during rapid strikes, comparable to the defensive tail use observed in modern reptiles. These findings suggest that tail-whipping may have played a role in predator deterrence and intraspecific interactions in Plateosaurus.