The origin of the name “nurse shark” is unclear. It may come from the sucking sound they make when hunting for prey in the sand, which vaguely resembles that of a nursing baby. Or it may derive from an archaic word, nusse, meaning “cat shark”. [x]
Very unlikely. As much as I’d like to believe such an amazing creature still exists, it most likely doesn’t anymore.
Megalodons went extinct an estimated 1.6 million years ago. Sharks also regularly shed teeth, but no one has discovered any Megalodon teeth that indicate they were recently lost.
Another idea that sometimes crops up – could Megalodon be hiding in really deep oceans, escaping our detection? Probably not. Fossil evidence from Megalodons suggests that they preferred shallower, warmer waters and would have inhabited areas rife with large prey needed to sustain their populations. They also used coastal areas as nursing grounds. Furthermore, it’s thought one of the factors that may have contributed to their extinction was the migration of their prey to colder waters, restricting the prey available to them. They just were not adapted to life deep in the oceans (we’re talking really deep here for something this ginormous to be able to escape detection).
We’ve only explored a tiny portion of our oceans. But the vast majority of ocean life lives in the first few hundred meters, where the sunlight can reach. Below that, life becomes highly specialized and large animals are rare. Megalodons were HUGE and would need a constant supply of large animals to feed off.
Many people are really hooked on the idea that Megalodon is still alive, but science has given us enough evidence to say no.
Blacktip sharks have been known to leap above the surface, rotate several times, and splash down on their backs, sometimes as part of a stealthy feeding method to attack schools of fish near the surface.
The frilled shark has been recorded living in a number of widely scattered locations in the Atlantic and Pacific Oceans, however sighting are fairly uncommon.
Lemon sharks feed at night and mainly eat fish, but have been known to feed on crustaceans and benthic organisms. Cannibalism of juveniles has also been documented.
ifesbob 