 Fish, Vertebrates of the Sea Image source

What do you think make fish different from all other vertebrates? Discuss with your team, then we will brainstorm as a group.

Fish  There are over 25,000 species, or types of fish. Even if you combined all of the other vertebrate classes together there would still be more fish than mammals + reptiles + amphibians + birds!  Fish are aquatic  Aquatic: growing, living or taking place in water  Some fish live in salt water, some in fresh water, and some in both! Fish are found almost everywhere in the world. Some fish are even found in hot desert springs!  Almost all fish fish are ectothermic, or cold blooded Image source

How do fish breathe?  Fish breathe through their gills. The water passes through their gills and they extract, or pull out, the oxygen from the water.  Notice how there are layers of gills.  Do you think this is a good design? Why, why not? Image source

What do you know about the outside of a fish?  Most fish are covered in scales and slime.  Why would fish need scales?  Scales protect the fish just like your skin protects you.  On top of the scales is a slime layer.  This protects the fish from bacteria and parasites in the water.  Helps them move through the water. Image source

How does a fish swim?  Fish flex their bodies making like a wave motion. Their fins play a very important part in their ability to swim.  The tail fin, called the caudal fin, helps it steer and propel forward.  The dorsal fin helps in turning suddenly and most importantly, it helps keep the fish stable, keep balanced and for protection.  The pectoral fins help it swim in place and stay balanced.  The pelvic fin helps the fish turn, stop and balance Image source

What other traits do most fish have? AAll fish have the same 5 senses humans have BUT they also have a 6 th sense! AAll fish have a canal made up of tiny little holes running the length of the fish, from head to tail, just under the scales. This is called the "lateral line " which allows them to detect water vibrations. WWhy would this trait be important and necessary for a fish? Image source

We know that all fish have common inherited traits. There are some specific traits that have helped it adapt, or get used to and survive in its habitat.

One of these traits is the shape and position of the fish’s mouth. Depending on the shape and position of the mouth, you can identify where the fish feeds and where its habitat is located. Lets take a closer look.

There are 3 different fish mouth positions. Work with your partner and discuss how the fish will feed. Image source

Let’s take a look at what each team decided. Everyone else will move to the next group and hear their reasoning. It may, or may not, match your team’s choices or reasons. Then the recorders will follow.

Fish with a terminal mouth location. The mouth is located right in the center of its head. Think like a fish. How will you get your food? Feeds by fish swimming towards it. Fish with this type of mouth are middle water feeders.

Fish with a superior mouth location. The mouth is pointing upwards. Think like a fish, how will you get your food? Fish with this type of mouth location feed on food located above it.

Fish with an inferior mouth location. The mouth is pointing downward. Think like a fish, how will you feed? Fish with this type of mouth location feed on food located below it.

We’ve learned many new facts about fish today. How many parts can you identify?

 Image source