Tuesday, March 29, 2016

Blooming of March Spring. Saga of Triassic. Antetonitrus

The holotype fossils of Antetonitrus were originally found in‭ ‬1981,‭ ‬but were thought to be further fossils of the genus Euskelosaurus.‭ ‬It was not until over two decades later that they would be correctly described as a distinct genus.‭ ‬Antetonitrus is a very interesting sauropod dinosaur,‭ ‬as while it was quadrupedal‭ (‬walked on four legs‭)‬,‭ ‬the fore limbs are not as well adapted for bearing the weight of the animal as later,‭ ‬more advanced sauropod genera.‭ ‬The first digit of the fore feet,‭ ‬comparable to your own thumb,‭ ‬is still twisted and opposable against the foot.‭ ‬As time would go on and more advanced forms appeared,‭ ‬the bones grew so large for additional weight bearing support that flexible movement between the bones of the fore foot would become impossible.‭ ‬Therefore,‭ ‬as a genus,‭ ‬Antetonitrus is a transitional link between the mostly bipedal prosauropod dinosaurs that emerged earlier in the Triassic,‭ ‬and the later quadrupedal sauropods that began to become commonplace as the Jurassic went on.‭
       Aside from the fore feet,‭ ‬Antetonitrus appears to have been a fairly typical sauropod that roamed around using its long neck to reach plants to feed.‭ ‬The skull is still not known at the time of writing,‭ ‬so it is still unknown if Antetonitrus had any specialised feeding adaptations that may indicate a preference towards certain plant types.‭ ‬The vertebrae of the holotype individual are also interesting in that the neural arches‭ (‬the spiky parts of the vertebrae‭) ‬are not fused with the centra‭ (‬the round bit that encloses the spinal cord‭)‬,‭ ‬which indicates that this individual was not fully grown.‭

No comments: