Gain and loss of biodiversity

Niloofar Alaei Kakhki

Climate change is dramatically altering the natural world, and many animal species are struggling to keep up. Whether they can adapt to these new conditions depends largely on one crucial factor: genetic diversity. The greater the genetic variation within a species, the better its chances of survival. To illustrate this, I present two examples of how songbird plumage coloration has evolved, highlighting the roles of convergent and divergent evolution in colour genes.

In closely related wheatear species, genetic diversity related to plumage coloration allowed them to quickly adapt to new food sources. This sharing of genetic variants led to convergent evolution, with different species developing similar colour patterns independently. In contrast, more distantly related species needed much more time to adapt, as they relied on slow, gradual genetic changes accumulated over millions of years.

A different pattern is seen in closely related buntings. In these birds, the genomic regions associated with colour patterns function as barrier genes, despite the huge amount of gene flow for rest of the genome. These barriers are allowing species to maintain distinct.