Friday, June 4, 2010
In prepping for the volunteer training, I asked myself - What is a fish?
They are a remarkably diverse group. I liked the definition I found in a text by our own Dr. Brian Bowen. "A fish is an aquatic vertebrate with gills and with limbs in the shape of fins."(1)
This covers a wide range of organisms including sharks, rays, sturgeons, lungfish, and all of the bony fishes (from goldfish to butterflyfishes).
Some superlative fish facts from the book:
Fish lifespans range from 10 weeks (2.5 months) for pygmy gobies, to over 150 years (sturgeon and some rockfishes).
Lungfishes can live in a state of dry "suspended animation" for up to 4 years.
Antarctic fishes live in water that is colder than the freezing point of their blood (they have a natural "antifreeze" in their system).
Picky about your food? Some fish have specialized in eating: the parasites off others, eating other fish's scales, young, fins, feces, or even eyes.
They may inflate themselves, wiggle lures, play dead or create light, warm their blood, and create their own sunscreens - all adaptations that help different fish survive and reproduce.
All of this in a group of animals that range in size from less than 1/3 of an inch (Paedocypris progenetica - a tiny carp relative) to over 52 feet long (whale sharks - because, of course, sharks are fish too).
1. From, "The Diversity of Fishes, Biology, Evolution, and Ecology." 2009. Helfman,Collette, Facey, Bowen (that would be our Dr. Brian Bowen).
Posted by HIMB CEP at 12:06 PM