As its name implies, the icefish is cold-blooded. But it’s also clear-blooded. It’s the only known vertebrate in the world that doesn’t have red blood cells -- or the protein that gives those cells their color.
The first icefish was discovered in the 1920s in the Southern Ocean, which surrounds Antarctica. It was called the white crocodile icefish. It has a see-through body -- you can even see its brain -- plus big eyes and a long snout with a lot of teeth, like a crocodile.
Whether it’s a swagger or waddle, a strut or a prance, the way a person walks can reveal a lot about their personality before they say a word. It turns out, the same may be true for fish. We don’t exactly have words, yet, for what a swordfish’s swagger or a sturgeon’s strut might look like, but scientists may soon. A group of researchers recently documented the fin movements of three-spined sticklebacks and found them to be distinctive enough to identify each fish by how it swam.
