Dinosaur 'Tanks' and their Tail Clubs

Published: 3rd Sep 2015

A new study has looked at the development of the ferocius tail club in dinosaurs like Ankylosaurus and its cousins. Early members of the ankylosaur group which originated about 160 million years ago in the Jurassic did not have a tail club. They were still heavily armoured with bony nodules and spikes.

Firstly in the evolution of the tail club the vertebrae in the rear of the tail changed so that the tail became stiff. Next, bones that form in the skin to provide body armour, called osteoderms, became very large at the tip of the tail and eventually completely enveloped the tail's end to form a club that could be swung. It was not until 75 million years ago in the late Cretaceous that the first fully formed tail club is known.

Ankylosaurus measured around 6 meters in length and was the largest and last of the ankylosaurs. It lived at the end of the age of dinosaurs in what is now America and could well have used its tail club to fight off attacks from huge predators such as T rex. Another use may have been for batlling other ankylosaurs in a similar way that deer use their antlers to fight amongst themselves.