what accounts for the similarities in life forms found in the same type of biome in geographically separated areas?

It is due to convergent evolution, which is the mechanism by which non-related organisms evolve similar characteristics separately as a result of having to acclimate to similar environments.

The analogous nature of insect wings, birds, pterosaurs, and bats is an example of this. All four serves the same purpose and in form are identical, but each has developed differently, not from a single winged ancestor.