Which pair of organisms show convergent evolution?

A convergent evolution is a phenomenon of independent evolution of similar traits in species that are in different lineages. These traits are similar in form or function but were not present in the last common ancestor of those species.

There are many examples of convergent evolution among plants and animals. Among the plants, both cactus and euphorbia are succulent plants, have spines, live in the deserts, but they belong to the different families. Further, dolphin, which is a mammal, is more similar to fish, than to other mammals. Or, both birds and bat, which is the mammal, have wings. So, all these examples of convergent evolution suggest that the living in the similar environmental conditions led to development of similar forms between distinct species.