While the evolutionary history of most sharks show them adapting to become faster and stronger, the evolution of angel sharks show how the species took a different approach to being one of the ocean’s apex predators.
Angels sharks date back nearly 160 million years. The earliest of those fossils show that they were very similar to the angel sharks that still exist today, according to a new study by the University of Vienna.
Using skulls that date back to the Jurassic era, X-ray and CT images showed the evolution of body shapes could be explained comparatively, independent of body size. Results showed that early angel sharks were different in their external shape, whereas modern species show a comparably lower variation in shape.
“The effect of integrating different parts of the skull into individual, highly interdependent modules can lead to a limited ability to evolve in different forms, but at the same time increases the ability to successfully adapt to specific environmental conditions,” explains Jürgen Kriwet.
Increasing geographical isolation resulted in the development of different species with very similar adaptations.
“Modular integration also means that such animals are no longer able to react quickly to environmental changes, which increases their risk of extinction,” Kriwet said.
The full results of the study can be found in the latest issue of Nature.