A new study finds thousands of imperiled plants and animals meet Endangered Species Act criteria yet remain unlisted.

Tuna, opah, and billfishes such as marlins and swordfish are among the 0.1% of fish species that are warm-blooded. Evidence by an international team of researchers led by UC San Diego’s Scripps ...

Have you ever wished you could swim like a fish? How about speak like one? In a paper recently published in the Journal of ...

The old idiom of being a fish out of water is never a positive thing. Instead, it paints a picture of being uncomfortable or awkward. This is how most fish feel when they are removed from their ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Some types of sea ...