Posts

Showing posts from January, 2023

Fossil Friday #4 - Phorusracids (Terror Bird)

Image
66 million years ago, the K-Pg extinction event saw the end of the (non-avian) dinosaurs. This marked the beginning of the reign of mammals on earth, as they were able to diversify and evolve to fill almost all niches that were previously unattainable during the Mesozoic era. As with any trend in evolutionary biology, there are always outliers. Up until  ∼ 100,000 years ago, South America was ruled by a group of theropods, the Phorusrhacids, also known as the Terror Birds. A diverse group of birds, 18 species have been discovered so far, mostly in South America, an area that produced some of the Cenozoic's most astonishing animals, due to its isolation from the rest of the world up until the land bridge between North and South America was formed  ∼2.6ma (AZ Animals, 2020). The type specimen, belonging to Phorusracos longissimus , is of a fragmented mandible, equalling 60cm in length, and was discovered by Florentino Ameghino at the Santa Cruz formation, Patagonia in 1887. At first,

Fossil Friday #3 - Helicoprion

Image
Palaeontology shows us a wide range of species that may not have even been imaginable had it not been for fossil evidence. The same could be said about some of the wonderful ocean life that lives on our planet even today. When looking at prehistoric wildlife, some of the wildlife that used to live in earth's oceans took incredible forms that would look out of place in our world today. Many of these animals are difficult to reconstruct even with fossil evidence that has been uncovered, and such has been the case with the Permian eugeneodont, Helicoprion . The signature feature of Helicoprion , the tooth-whorl, is what has made it difficult to reconstruct. Being a cartilaginous fish, the rest of the body is rarely preserved, so the tooth-whorl is the only evidence that exists of this fish. What has also made this so puzzling for reconstruction is the fact there is nothing alive today that resembles this feature, which makes it difficult to apply the theory of uniformitarianism; the i

Fossil Friday #2 - Paraceratherium

Image
One of the main assets of ancient life that first drew me to Palaeontology as a child is the sheer size of some of the animals that used to walk this very earth. Of course, the dinosaurs are the most famous example of this and are a group that contains the largest terrestrial animals to ever grace our planet. It is not just the dinosaurs, however, that could grow to such sizes that are almost unimaginable to envision in today's world. More recently than the dinosaurs, there were some truly outstanding now-extinct mammals that would dwarf any other land animal that is alive today. One of the most extreme examples of this is the Paraceratherium.  This truly remarkable animal was first discovered in Pakistan, a place where many impressive mammal fossils have been discovered, such as the ancestors of modern-day whales, which are more resemblant of dogs and rodents, rather than marine mammals. The first studied specimens of Paraceretherium were discovered by British geologist, Guy Ellco