Fish pee just like humans do to excrete metabolic wastes. Some species produce a concentrated, somewhat yellow-hued urine that is quickly dispersed in their aquatic world. Besides water, fish pee is ...

Most complex organisms have a permanent hole for excreting waste. (Though there are exceptions, like the warty comb jelly, which forms an anus only when nature calls.) In bipeds and quadrupeds, the ...

Researchers are working to prove that coral-eating fish spread corals’ symbiotic algae in their feces. If they’re right, it could open new opportunities for helping struggling reefs cope. By Derek ...