Strange Sea Creatures Were the Earliest form of Vertebrate Life
by Dilma Attidekou, age 7
Did you know that the first fish were unable to bite with their jaws but rather they sucked up their prey from the mud?
Around 500 million years ago, the first fish appeared. As protection, these early fish had hard, curved plates of bone all over their bodies. They also ate differently. Some sucked their food while others were strong hunters with sharp bones in their jaws to cut up their food.
Ancient fish looked very different from fish today. Some could walk out of water. Other ancient fish look like sharks. They were spiny and had big teeth. Many types of early fish were fierce hunters. Over time, ancient fish changed to look like modern fish.
One example of an ancient fish is the Hemicyclaspis. It was an early fish that lived on the seabed. Although it had no jaw, it was still able to look out for predators since it had eyes on top of its head. A second example is the Eusthenopteron, a kind of lobefin. They could walk from one pond to another. Lastly, the Climatius was a spiny ancient that was as small as a toe. They lived in rivers and lakes.
Over time, ancient fish changed to look like modern fish. ancient fish are interesting to learn about because they are different from the fish we see in lakes, rivers, oceans, and aquariums today. Learning about these ancient fish helps us appreciate modern fish and study how they transformed into the creatures we see today.
[Source: 100 Things You Should Know About Prehistoric Life]