What is a fish?
Like all animals in the Animal Kingdom, a fish is a multicellular living organism that lacks chlorophyll or a rigid cell wall. But what makes a fish different from every other animal in the animal kingdom? Fish have some unique traits unlike any other animal in the animal kingdom.
Scales
Fish are not the only animals in the Animal Kingdom to have scales, but theirs are pretty different from something like a reptile. Whereas reptile scales are made out of keratin, fish scales are closer to teeth. They are made out of enamel and dentine, similar to human teeth. They can also come in different shapes, placoid, cycloid, ganoid, and ctenoid.
Egg Laying
Remember in our previous blog that reptiles lay eggs on land. Fish, however, usually lay eggs in the water. Some fish lay their eggs inside their own bodies and release their babies when they hatch into the water.
Gills to Breathe
Fish are found in the water, but like all animals, they need some form of oxygen. They don’t have blowholes like the dolphin from class Mammalia. Instead, they have gills. These open ridges of tissue on the sides of their body allow oxygen to diffuse through the gills and into their tissue straight from the water.
Where do fish live?
Fish can live in freshwater, saltwater, or something in between known as brackish water. One of the busiest fish environments is our coral reefs. Coral reefs are responsible for the largest amount of biodiversity in the world (terrestrial and aquatic). They harbor around 25% of the world’s fish species. This means they are vital to keeping our oceans alive and healthy.
How can I help keep my ocean safe?
Reduce your plastics. This is one of the easiest at-home ways to contribute to keeping our oceans safe. Billions of pieces of plastic enter our oceans each year. They wound coral reefs, strangle fish, and much more. Another easy way is to stay educated and share that education with friends and family. The more people that know and care about the importance of our environment, the easier it will be to fix it.