The Elements of Evolution (44) Convergent Evolution

Convergent Evolution

There is a pervasive occurrence of convergence across the tree of life. Many roads can lead to evolved similarity in disparate branches. ~ Hungarian evolutionary geneticist László Nagy

Convergent evolution (aka parallel evolution) is the acquisition of the same trait in unrelated life forms (different clades). (Selfsame trait evolution is considered parallel between organisms if both ancestors had an antecedent similarity that can be pointed to as the genomic foundation for the trait’s development, or convergent if not. Considering our limited knowledge of the genetic dynamics involved in adaptation, making such a distinction is often problematic.) Instances of convergent evolution are voluminous.

The fact that many solutions are used over and over again by completely unrelated species suggests that the evolutionary path is repeatable and predictable. ~ Peter Andolfatto

Convergence in Nature is more common than many biologists would have wagered not long ago. Nonetheless, convergence is not inevitable – in many cases, lineages adapt in different ways to the same environmental conditions. ~ American evolutionary biologist Zachary Blount et al