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A timeline Of SHARK EVOLUTION (prehistoric till present day)
12 April 2018
Sharks are 450 million years old and have been on this planet longer than almost any other animal. They have lived through every major mass extinction event and have survived long past many of their competitors. With over 3,000 species spanning nearly half a billion years, sharks are one of the most evolutionarily successful animals to ever live. Tracking their evolutionary history, we can learn about these amazing species and how they came to their modern forms.
Most of the sharks on the planet have developed in the Cenozoic era, except for the truly ancient sharks from the Cretaceous period. The newest shark species to enter the water is the Hammerhead Shark. Hammerhead Shark evolution only dates back about 20 million years. Currently there are around 440 species of shark swimming in our oceans, however every year scientists are finding more unique species.
Time line of shark evolution
1. 514 million years ago : Metaspriginna was the oldest known fish-a sector of all jawed vertebrates.
2. 370 million years ago : Cladoselache was the earliest and most well-known shark. Its jaw was fused to its head.
3. 330 million years ago : Falcaus had a dorsal spine and large eyes w.r.t to its tiny body.
4. 320 million years ago : Stetacanthus had tooth-like skin preventing injury
5. 290 million years ago : Helicoprion had a jaw curved into a swirl shape. By this time sharks were able to grow teeth faster.
6. 180 million years ago : Hybodus had extremely sharp canine teeth and flat grinders in the back like a modern day bull shark.
7. 100 million years ago : Ginsu shark was one of the most modern sharks of its time.
8. 55 million years ago : Otodus was huge (30ft-39ft in length). It was the earliest known relative of all mackerel sharks.
9. 15.9 million years ago : Megalodon, meaning BIG TOOTH was one of the largest and fiercest predators ever. Fossil remains of megalodon suggest that this giant shark reached a length of about 59+ ft.