The two groups of bony fishes, the actinopterygii and sarcopterygii, evolved and became common. ... The later radiations, such as those of fish in the Silurian and Devonian periods, involved fewer taxa, mainly with very similar body plans. The first animals to venture onto dry land were arthropods.

What caused fish to evolve?

Therefore, it seems likely that fishing causes evolution in fishes. Selective harvest of experimental populations has produced genetic changes in them, and natural selective agents, especially selective predation, have also caused genetic changes in populations of various species.

What was the first fish on earth?

The first fish were primitive jawless forms (agnathans) which appeared in the Early Cambrian, but remained generally rare until the Silurian and Devonian when they underwent a rapid evolution.