Many frogs look like a water balloon with legs, but don’t be fooled. Beneath slick skin, some species sport spines, spikes and other skeletal secrets.
While most frogs share a simple skull shape with a smooth surface, others have evolved fancier features, such as faux fangs, elaborate crests, helmet-like fortification and venom-delivering spikes. A new study is the first to take a close look at the evolution and function of these armoured frog skulls.
Florida Museum of Natural History researchers used 3D data to study skull shape in 158 species representing all living frog families. Radically shaped skulls were often covered in intricate patterns of grooves, ridges and pits formed by extra layers of bone. The research team found that this trait, known as hyperossification, has evolved more than 25 times in frogs. Species with the same feeding habits or defences tended to develop similarly shaped and patterned skulls, even if they were separated by millions of years of evolution. MORE