In Depth
The discovery of Padillasaurus has been a very important step in South American palaeontology as it represents the first confirmed genus of a brachiosaurid sauropod dinosaur that is known on this continent (though isolated and very fragmentary remains have been found before, they were not complete enough to name a genus). Unfortunately the only known fossils at the time of writing are some eleven vertebrae, which makes it very difficult to figure out not only distinctive features, but also even simple information such as the size given that we don’t even know how long the neck was.
However, if we assume that Padillasaurus had the same approximate body proportions as Brachiosaurus, the genus that the Brachiosauridae is named after, and then scale our reconstruction so that the first eight caudal vertebrae combined measure about 115-116 centimetres of the length, then this would give us a result of about fourteen meters long (measured by curvature) for the full dinosaur.
Some things that we can infer about Padillasaurus is that by living in Barremian stage of the Cretaceous, it was one of if not the last brachiosaurid sauropod dinosaurs to exist in Gondwana, the southern collection of the continents during the Mesozoic. A good question would be how did Padillasaurus reach South America? For a long time popular science publications claimed that after the Triassic South America was completely isolated from the rest of the world, but today we now know that is simply not true.
The presence of spinosaurid and carcharodontid dinosaurs in both South America and Africa is proof that animals were travelling between the two continents all the way up until the early Cretaceous. Brachiosaurid sauropods, most commonly associated with North America are also known from Europe as well as North Africa, creating a picture where they may have travelled the long way around to South America. Something possible since there also seems to have been limited faunal interchanges between at least Western Europe and North Africa given the presence of very similar dinosaur types in both areas. This journey would probably not have been taken within the space of a single lifetime, but over the course of hundreds, maybe even tens of thousands of years by successive generations. Brachiosaurid genera that lived in Africa include Giraffatitan, which lived during the late Jurassic, and it may have been individuals from these genera that crossed over into South America. Only time and future fossil discoveries will tell for sure.
Further Reading
- A new Early Cretaceous brachiosaurid (Dinosauria, Neosauropoda) from northwestern Gondwana (Villa de Leiva, Colombia). - Journal of Vertebrate Paleontology 35(5):e980505:1-12. - J. L. Carballido, D. Pol, M. L. Parra Ruge, S. Padilla Bernal, M. E. P�ramo-Fonseca & F. Etayo-Serna - 2015.
