Fish Review

Fish Anatomy (two minute time limit)
Open the links below in a new tab and play "Scatter" or "Space Race" with BOTH sets. Please do not spend more than five minutes on each (ten minutes total).
Fish - caudal fins, mouths, body shapes and coloration
Unit 7 Fish Words and concepts including harvesting

Tuesday, October 25, 2016

Fish Bodies and Shapes

Today in class we discussed fish mouth shape and body shape and what they mean about the fish.
Many fishes are identified by looking at or into the mouth. The number of mouth-types exhibited by different species is nothing short of astonishing. Three lakes in Africa contained about 900 species of cichlids, nearly all differentiated mainly by the way their mouths are shaped. (This number is rapidly dwindling, by the way, as the cichlids in these lakes are driven to extinction). Cichlid mouths are variously adapted to eat other cichlids' eggs, scales pulled from fishes' living bodies, algae from rocks, tiny invertebrates, and many other forms of food. The arrowana of South America has a mouth adapted for spitting water with precision at insects perched on overhead branches. Parrotfish mouths have evolved to look and act like beaks, which they use to grind at coral, making the sand that surrounds coral reefs. Seahorses and pipefish have tubular mouths for sucking in small prey in narrow places like a vacuum cleaner.  SOURCE

Fish with forward facing mouths eat what is in front of them - no surprise. Downward mouths eat algae, prey below them like crustaceans and molluscs, or they take in mouth fulls of gravel, eat the particles, and spit the gravel back out. Upward facing mouths indicate the fish eats prey above them - typical of benthic ambush predators. There are also bills and beaks. Bills are long and skinny used for poking in crevices and eating plankton one at a time. Beaks are used for chomping and can be seen on the parrotfish, a fish that chomps on the algae growing on the surface of dead coral. Fish can also have very large mouths common on filter feeders and fish that swallow large prey whole. Fish also have teeth - a surprise to many - and come in many shapes and size.

Body shape also tells you a bit about a fish. Com- pressed fish have flash and look skinny and can only be found in slow moving waters like coral reefs. Fusi-form fish are tapered like footballs and are very streamlined for constant fast swimming. Depressed fish are benthic and squashed looking. Eel shaped fish are poor swimmers and live on the benthos or in cracks and crevices.

Here is a website you can use to identify shapes - realize they are named a bit differently than how I do in class.

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Computer Lab Etiquette

You are in the computer lab to do work for this class. If you are not doing work, then we will have problems.

Do not pack up early. Work until the bell or until MsJ says.

SAVE OFTEN. And if you save to a key, also save it to your number. If you lose it, you will have to do it again.

If MsJ asks for your attention, stop what you are doing and listen to what she has to say.

You may watch videos about your organism through reliable websites.

You may listen to music through the computer if you have your own headphones. Rule1 MsJ cannot hear it. You get one warning. Rule2 Turn it on and listen – no million clicks and constant changing. Take both ear phones out when MsJ is talking.