Selachophobia is the name for fear of sharks. There are many people in the world who wouldn’t dare enter a sea or an ocean because of this. They believe they are safe on land. Now, researches have identified a few species of sharks that can walk on land. While it might be a Selachophobic’s nightmare, these sharks are not particularly that dangerous.
Meet the walking sharks, who live near Australia. They are three-foot-long and move along the seafloor—or even atop coral reefs, outside the water, at low tide using their pectoral and pelvic fins. Sharks are known for their slow rate of evolution. Even after being around for hundreds of millions of years most species of sharks have barely changed. But somehow these sharks are showing tremendous rates of evolution, that too in a recent time period.
The kind of mobility these “Walking sharks” has allowed them to wriggle between tide pools and different areas of the reef to prey upon crabs, shrimp and small fish. According to Christine Dudgeon of the University of Queensland in Brisbane, Australia, “During low tides, they became the top predator on the reef.”
In a paper published in this week’s Marine and Freshwater Research journal, researchers have discovered four new species of the walking sharks, making the total tally nice. The study shows that these species all evolved in the last nine million years.
Gavin Naylor, director of the Florida Program for Shark Research at the University of Florida calls this “highly unusual” since most sharks evolve slowly. Naylor says that the rich coral reefs in the walking sharks’ range are dynamic, shifting continually over recent epochs as sea levels rise and fall, currents shift, reefs flourish or wither, and temperatures change. This dynamism is likely what’s driven their speedy evolution and diversity.
Like most sharks, these are also under the threat of overfishing and harvesting. Being recently discovered the data on these fishes are yet to be made comprehensive. For now, none of the species is thought to be endangered. But if they were to be under severe threats they could easily go extinct as their population is small and concentrated only at certain parts of the sea- near Australia and Papua New Guinea.