(CNN) So -- some sharks walk. Just not the scary ones.

While great whites haunt the deep, walking sharks are content to scuttle in the shallows.

They've been walking, or something close to it, for at least 9 million years.

They're evolutionary superstars, too: Walking sharks could be the most recently evolved shark on Earth.

That's according to findings published this week in Marine and Freshwater Research . Shark scientists spent years sampling the DNA of the only known walking shark species to estimate when they evolved. They found four new species while they were at it.

Read More