By Andrew Shankster

Sharks. Owners of an iconic visage, cutting a notorious and well-known shape through the water, established as a deep-sea terror by films such as Jaws; but this is an undeserved reputation.

Sharks pre-date humanity, dinosaurs and big marine reptiles, with the first evidence of their existence (fossilised scales to be exact) dating back to the Silurian Period (440-420 million years ago).

 

VOTE NOW for Sharks in our Jurassic Coast Big Five competition

 

hybodus shark teeth

Specimens of fossilised Hybodus (a prehistoric shark species) teeth from Dorset County Museum. These are approximately 152 million years old.

 

But what makes sharks so beautiful? Is it their sheer size and predatory prowess? Is it their longevity? No. What makes shark so interesting is the variety of adaptations they have developed which, given their longevity, is considerable.

This variety in ecological adaptation can be seen in the fossil record, with the Asteracanthus shark sporting spines along their dorsal fin to deter predators, a technique employed by the modern-day Horn Shark. The prehistoric Acrodus and Gyrodus sported large, flat and rounded teeth employed in the breaking and crushing of shells.

Personally, I feel the epitome of the variety of sharks can be found in the prehistoric Hybodus shark, which sported two different kinds of teeth, enabling it to eat slippery fish but also to crush shelled marine life. All four of these prehistoric sharks have been found fossilised along the Jurassic Coast.

All these examples of the sheer variety of sharks within the ecosystem both in past and modern eras, coupled with the fact a lot of the adaptations evolved by ancient sharks are still present nowadays in the marine ecosystems, are why you should vote for them!