The amazing story of the coelacanth is one of the wonders of the living world that inspires marine biologists such myself. Coelacanths, part of the offshoot lineage of fishes known as "lobed finned ", are very different from typical "ray finned" fishes that you usually think of. Their bizarre lobed fins are thought to be an intermediate step between fish fins and amphibian legs. Scientists had known that these weird fish existed because of fossils for over a century, but we believed that they went extinct 65 million years ago... until a South African fisherman caught one in 1938. [more inside]
posted by WhySharksMatter on Sep 7, 2009 - 49 comments

Australian scientists have found the world's oldest penis. Published Monday in the online version of Nature, the discovery of the 400 million-year-old clasper in an ancient fish specimen shows that animals were gettin' it on earlier than previously thought. Says one study author, "We were surprised because it's so big. We were expecting something smaller." SFW
posted by Dilemma on Jul 16, 2009 - 34 comments

A fish with forward facing eyes has been discovered in Indonesia. [more inside]
posted by chuckdarwin on Apr 3, 2008 - 47 comments

After two big Antarctic ice shelves broke off several years ago, a world of new species was found underneath. Pictures and a press release came out yesterday, showing spindly orange starfish among other interesting creatures. Here is some more information on the expedition. The fact that the shelves melted when they did is most likely a result of global warming, but having them out of the way gave researchers a golden opportunity to study what lives beneath the ice. Other occassions where a disaster has simultaneously been a great research opportunity include radioactive fallouts: at Chernobyl the evacuated area has been monitored for the past decades to see which species move in and how they thrive (previously on Metafilter)
posted by easternblot on Feb 26, 2007 - 21 comments

White Shark Released from Monterey Bay Aquarium after six months in captivity. In the last week, aquarists noted several incidents of what they considered to be active hunting of other exhibit animals, and they became substantially more concerned about the well-being of the other fishes. She was not released because of any injury or health problem. At the time of her release, she was 6'-4" long and weighed 162 pounds.
posted by rodo on Mar 31, 2005 - 19 comments

Cuter than a fangtooth. Beautiful images of bioluminescent sea creatures. Learn the difference between fluorescence, phosphorescence, and bioluminescence, as well as the science behind the amazing chemical reaction. (I like the floppy-eared one the best--okay, the plastic bag looking one is nifty too.)
posted by lychee on May 12, 2004 - 4 comments

Blind cod, netted 40 times, retires to aquarium.
posted by jpoulos on Feb 8, 2001 - 5 comments

And thanks to all the fish? British researchers say fans of loud music may be responding to a 'pleasure-inducing hearing mechanism' passed down through evolution from fish to humans. Well, slap me with a large trout!
posted by prolific on Feb 17, 2000 - 4 comments