Opahs, the only warm blooded fish species, are cold-blooded killers.
Everyone has dealt with cleaning the messy lint filter after several wash cycles, but not all the lint gets trapped.
Find out which fish will survive best in your little fishbowl!
Step (or swim) right up for a free scale cleaning! Cleaner wrasse provide a very valuable service for their underwater clients.
Our planet is inhabited by a host of strange and remarkable creatures, but few as strange or remarkable, if you ask me, as hagfish. Hagfish are eel-like fish about a foot long. They have a small mouth that lacks jaws and teeth. Learn more on this Moment of Science.