Lystrosaurus – a stout survivor


Well this is an example of a dicynodont, this one’s called Lystrosaurus and this was an interesting sort of plant-eating reptile because it didn’t actually have any teeth. It did have these two tusks here at the front and this area here at the front would have had a beak-like structure on it, a bit like you see on tortoises today. The build of the animal is basically fairly stocky; it’s got short powerful arms and legs, a fairly short tail, I guess in a lot of ways a bit like a reptilian wombat.

There was something very successful about the body plan of dicynodonts; they soon evolved into a number of different forms but they were one of the most abundant and successful land animals. Some of them were tiny, they were the size of a rat, others were getting up to the size of a hippo.

Well at the end of the Permian, about 250 million years ago, there was a massive extinction event that wiped out about 95 percent of life on the planet. We think it might have been caused by volcanoes and that triggered changes in the atmosphere, also chemistry in the oceans, but it was a huge event that wiped out 95 percent of life.

We may never know exactly why an animal like Lystrosaurus survived a mass extinction event. There are a couple of different reasons that we think could explain it; one of them might have been that it wasn’t particularly fussy about what plants it ate — there were lots of plants that survived the extinction event. Another reason could be it may have lived at higher altitudes and be pre-adapted to lower levels of oxygen, so we are quite lucky that animals like this one did survive the mass extinction event because they ultimately went onto evolve into mammals which are our ancestors.

Lystrosaur fossils tell us a lot about how these animals lived but they also tell us a lot about the world in which they lived. In this case we’ve found fossils of Lystrosaurus in Africa as well as Madagascar and even in Antarctica. Now obviously these places are far apart today but during the Permian and the Triassic when this creature was alive, these land masses were all joined together and we now learn about the process of tectonic activity and land masses moving apart because of Lystrosaurus.

About this Video

Wayne Gerdtz, Museum Victoria, explains why Lystrosaurus was successful in the Triassic Period.
Length: 2:20