Untitled Document

Physical description

A fishes apperance is like no other. Fish can be as small as one inch to over six feet!. Most are long and skiny with two fins on their sides. Then is extendes into a sort of tail with two more fins on the end called tail fins. The tail fins provide most of the speed and the side fins direct it through the water. All of them have hundreds of scales all over their body (except for the fins).Their scales mainly have the same job as our skin. It holds the fish together and protects the insides. Between the side fins and he mouth are little slits the skin called the gills. The gills are for breathing. They are made of sheets tissue that can pick out bit of oxygen when water flowes through them.Fish are aquatic vertebrates so they have a back bone. It helps them maneuver faster in the water so they can get away from predetor. Or catch prey. Also fish are cold blooded. As you can see they have many advantages and disadvantages tohelp them survive.

Habitat

Fish can live almost any where that has water. The only exception would be in a man made yard pool or in water that is too polluted. Fish can eather live is salt water or in freash water, but their are some fish that can live in both freash and salted water. One example is the Atlantic Salmon because they live in salt water then go to freash water to mate. Freash water fish live mostly in lakes and rivers, but they also live in steams, swamps, and springs too. Salt water fish live in much bigger bodys if water though. They live in oceans, seas, and some rivers. Fish sleep in many different places. Most smaller fish live or sleep in water plants, under rocks, and coral. Much bigger fish live or sleep mainly eather out in the open or in some cases in the sand.

Natural history

Fish are said to be some of the first animals on earth. They were around a lot longer then the mammals and repties. Over time they have evolved a lot. They have evolved up to the Great White Shark. When some stayed as small as a gold fish. The fishes life starts as an egg where it grows intill it is big enough to hatch. Then it grows and feeds intill it is an adolt fish. When it is an adolt it then tries to find a mate so it can start it all over again. When the female fish lays the eggs the male fish then fertilize them. If the male dose not fertilize the eggs then they can not grow. There are about twenty eight, thousand species of fish now. Many people think that whales, and dolphins are fish, but they are mammals. They are very closely related though. There have been lots of storys about abnormal fish stories mostly called the one that got away. None have realley been proved true, but they are still fun to tell and listen to.

Acanthodii

Placodermi

Taxonomy

As I said before there are about twenty eight, thousand species of fish. There are six groups of fish. Osteichthyes, Chondrichthyes, Myxini, and Cephalaspidomorphi. There are two other, but they are extinct. they are called Placodermi, and Acanthodii. Osteichthyes take up most of the population, and Chondrichthyes take up the mainly the rest. Myxini and Cephalaspidomorphi take up very little of the population and lookmore like worms then fish. Examples of these are on the left. The fish look alike for the mast part but some things really stand out. For example the Placodermi has a more noticable tail and is more snake like then other fish. Also Myxini are very worm like and lots of them do not have any fins of any kind. That means no side fins or tail fins.

Osteichthyes

Chondrichthyes

Myxini

Cephalaspidomorphi

		Physical description A fishes apperance is like no other. Fish can be as small as one inch to over six feet!. Most are long and skiny with two fins on their sides. Then is extendes into a sort of tail with two more fins on the end called tail fins. The tail fins provide most of the speed and the side fins direct it through the water. All of them have hundreds of scales all over their body (except for the fins).Their scales mainly have the same job as our skin. It holds the fish together and protects the insides. Between the side fins and he mouth are little slits the skin called the gills. The gills are for breathing. They are made of sheets tissue that can pick out bit of oxygen when water flowes through them.Fish are aquatic vertebrates so they have a back bone. It helps them maneuver faster in the water so they can get away from predetor. Or catch prey. Also fish are cold blooded. As you can see they have many advantages and disadvantages tohelp them survive.
		Habitat Fish can live almost any where that has water. The only exception would be in a man made yard pool or in water that is too polluted. Fish can eather live is salt water or in freash water, but their are some fish that can live in both freash and salted water. One example is the Atlantic Salmon because they live in salt water then go to freash water to mate. Freash water fish live mostly in lakes and rivers, but they also live in steams, swamps, and springs too. Salt water fish live in much bigger bodys if water though. They live in oceans, seas, and some rivers. Fish sleep in many different places. Most smaller fish live or sleep in water plants, under rocks, and coral. Much bigger fish live or sleep mainly eather out in the open or in some cases in the sand.
		Natural history Fish are said to be some of the first animals on earth. They were around a lot longer then the mammals and repties. Over time they have evolved a lot. They have evolved up to the Great White Shark. When some stayed as small as a gold fish. The fishes life starts as an egg where it grows intill it is big enough to hatch. Then it grows and feeds intill it is an adolt fish. When it is an adolt it then tries to find a mate so it can start it all over again. When the female fish lays the eggs the male fish then fertilize them. If the male dose not fertilize the eggs then they can not grow. There are about twenty eight, thousand species of fish now. Many people think that whales, and dolphins are fish, but they are mammals. They are very closely related though. There have been lots of storys about abnormal fish stories mostly called the one that got away. None have realley been proved true, but they are still fun to tell and listen to.
Acanthodii	Placodermi	Taxonomy As I said before there are about twenty eight, thousand species of fish. There are six groups of fish. Osteichthyes, Chondrichthyes, Myxini, and Cephalaspidomorphi. There are two other, but they are extinct. they are called Placodermi, and Acanthodii. Osteichthyes take up most of the population, and Chondrichthyes take up the mainly the rest. Myxini and Cephalaspidomorphi take up very little of the population and lookmore like worms then fish. Examples of these are on the left. The fish look alike for the mast part but some things really stand out. For example the Placodermi has a more noticable tail and is more snake like then other fish. Also Myxini are very worm like and lots of them do not have any fins of any kind. That means no side fins or tail fins.
Osteichthyes	Chondrichthyes
Myxini	Cephalaspidomorphi