Out of Africa: A new hypothesis for the world’s biggest ever dinosaurs
Most of our most beloved and well-known dinosaurs tend to come from Europe and North America. Diplodocus, T. rex, Triceratops, all household names that have been known for decades now. Most of this reflects the fact that this is where most original professional dinosaur hunting and fossil collecting began, and entered into the attention of the media and public.
However, in the last couple of decades, we are seeing a huge surge in dinosaur discoveries from across South America, Asia, and Africa. Some of the largest dinosaurs ever known are being unearthed in Patagonia, and a huge diversity of feathered fiends have been collected from across China.
In Africa, recent discoveries have revealed a number of absolutely bizarre dinosaur species, really helping to shape our understanding of their incredible diversity. Recently, a new one was discovered and identified, given the name Mnyamawamtuka, from Tanzania. The species is from a group of giant sauropods with barrel-like bodies and long necks and tails called titanosaurs. During the Cretaceous period, these animals represented the largest to have ever walked the planet.
The full name of the new species is Mnyamawamtuka moyowamkia (Mm-nya-ma-wah-mm-too-ka Mm-oh-yo-wa-mm-key-ah), and is one of the most complete and oldest titanosaur skeletons ever found. It was named after its place of discovery along the Mtuka River in southwest Tanzania.
Its scientific name derives from Kishwahili (Swahili) words meaning “beast of the Mtuka” and “heart of the tail,” referring respectively to the location it was found and to the uniquely heart-shaped centrum of its tail vertebrae (‘moyo’ is the Kiswahili word for heart and ‘wa mkia’ is Kiswahili for ‘of the tail’). The rocks it was found in are part of the Galula Formation, and thought to be around 100-110 million years old, from a time known as the middle Cretaceous.
Mnyamawamtuka is closely related to other titanosaurs from the Late Cretaceous, specifically from South America. This suggests that there might have been a close connection between the two continents during the middle to later parts of the Cretaceous period. Such a pattern is also seen in other groups around at the time, such as the weirdly herbivorous crocodile-like animals known as notosuchians, which are known exclusively from the southern hemisphere.
“Although titanosaurs became one of the most successful dinosaur groups before the infamous mass extinction capping the Age of Dinosaurs, their early evolutionary history remains obscure, and Mnyamawamtuka helps tell those beginnings, especially for their African side of the story,” said lead author of the study, Eric Gorscak.
Of course, like all discoveries, this one opens up more questions that can only be answered by finding new fossils from the poorly sampled records of Africa. Time for a new expedition?
Citation: Gorscak E, O’Connor PM (2019) A new African Titanosaurian Sauropod Dinosaur from the middle Cretaceous Galula Formation (Mtuka Member), Rukwa Rift Basin, Southwestern Tanzania. PLoS ONE 14(2): e0211412. https://doi.org/10.1371/journal.pone.0211412