How does convergent evolution happen?
Convergent evolution is similar to parallel evolution, which occurs when two independent species evolve in the same direction and thus independently acquire similar characteristics; for instance, gliding frogs have evolved in parallel from multiple types of tree frog.
Convergent evolution is when different organisms independently evolve similar traits. For example, sharks and dolphins look relatively similar despite being entirely unrelated. ... Another lineage stayed put in the ocean, undergoing tweaks to become the modern shark.