Sharks do not sleep the same way humans or most animals do. Some species must keep swimming to push water over their gills, while others can rest on the ocean floor. Scientists have discovered that ...

1. Introducing sharks, skates, rays, and chimaeras -- What are sharks and how are they classified -- How many kinds of sharks are there -- How did sharks get their name -- Where do shards live -- When ...

Artificial light at night (ALAN) has a negative impact on shark melatonin levels, according to a recent study from the University of Miami.