What is the defining characteristic of convergent evolution?

The defining characteristic of convergent evolution is that it results in structures with different evolutionary origins that appear similar. This phenomenon occurs when unrelated or distantly related organisms evolve similar traits or adaptations as a response to analogous environmental challenges or niches, rather than inheriting these traits from a common ancestor. For example, the wings of bats and birds serve a similar function and exhibit similar structures, but they evolved independently in response to the need for flight.

This concept highlights how different species can develop analogous adaptations, which are not a result of shared ancestry but rather similar selective pressures in their environments. This is a key aspect of evolutionary biology as it demonstrates that similar solutions can evolve in different lineages, showcasing the versatility and adaptability of life on Earth.