What is the name of the evolutionary change in which unrelated species independently develop similar features?

Convergent evolution is the evolutionary change in which unrelated species independently develop similar features.

The similarities usually arise because different species face comparable environmental pressures or functional demands. Wings in bats and birds are a classic example: both are forelimbs modified for flight, although bats and birds evolved powered flight independently.

Convergent traits are often called analogous structures when they perform similar functions without being inherited from the same corresponding ancestral structure. This differs from homologous structures, such as the forelimbs of humans, whales, and bats, which reflect common ancestry even when their functions differ.

Convergence can also occur at molecular and behavioral levels. Similar body shapes evolved in sharks, ichthyosaurs, and dolphins because streamlined swimming is advantageous, despite their distant relationships. Similarity alone therefore does not prove close evolutionary kinship.