New dinosaur fossils from north Africa show that African dinosaurs could have stayed diverse until they reached their end. This also suggests that their demise was quite sudden, with a massive asteroid impact.

Wave of Mass Extinction

For two centuries, the causes of mass extinction have been a subject of debate. Georges Cuvier, who is known as the father of paleontology, believed that catastrophes drove extinction, while Charles Darwin thought that gradual changes in interspecies competition and environment slowly made certain lineages go extinct.

As fossil record understanding got better, it became known that the Cretaceous period ended with a massive wave of extinction. All over the world, a massive number of species ended up disappearing in just a brief span of time. The Chixculub asteroid impact crater discovery suggests that dinosaurs and other creatures suddenly went extinct. However, others have also argued that a slow and long decline in the diversity of dinosaurs could have contributed to the extinction of their species.

It has been quite hard to piece the story together as dinosaur fossils are quite rare and the fossil record is full of patches.

Most of what is known about the final days of dinosaurs is based on the study of a few places across Mongolia, Canada, and the US. Much less is known about dinosaurs from southern areas, such as Madagascar, South America, India, Antarctica, New Zealand, and Australia.

Until recently, hardly anything was known about the end-Cretaceous dinosaurs in Africa. The continent has a few terrestrial rocks that date back to this era due to the high volcanic activity levels that pushed sea levels up.

Being terrestrial creatures, dinosaurs rarely occur in marine sediments. However, there are several cases where marine fossils were found.

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New Dinosaur Fossils Found

Morocco's phosphate deposits are ancient seabed remains. This dates back to the dinosaur era's final million years. These are full of fish scales and bones, marine reptiles, and shark teeth. However, every now and then, dinosaurs show up, though it remains unclear how they ended up on such marine rocks.

Nevertheless, by looking into marine beds over the years, specialists were able to slowly come up with a picture of the last dinosaurs of Africa, including duckbill dinosaurs and titanosaurian sauropods.

Now, two new abelisaur fossils have been discovered in Morocco. The Abelisauridae family comprises carnivores that could be found in India, Europe, Madagascar, and South America. These creatures had bulldog, short snouts. They also had horns at times and stumpy, bizarrely small arms.

One of the abelisaurs is known from a shin bone. Based on dinosaur standards, it was quite small, with a length of roughly five meters. It curiously resembles the abelisaurs discovered in South America. It is possible that this could mark a prehistoric land connection that may have existed across continents around 100 million years ago. It may also imply that abelisaurs swum the thin sea way that separated continents.

Another bone comes from the food of a tinier abelisaurid that may have just been three meters in length. Similar abelisaurids of the same size have occurred in Europe, which suggests a possible association between them.

In the past months, more fossils of dinosaurs have surfaced.

Thriving Before Extinction

The last dinosaurs of Africa suggest that, right before they went extinct, these creatures may have thrived.

After more than 100 million years, they evolved and grew in diversity, leading to different species comprising herbivores, predators, aquatic species, and even avian forms. Then, a single catastrophe led to their full wipe-out, with a half-dozen bird species being the rough exemption.

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