Endangered songbird challenging assumptions about evolution – EurekAlert

Not all species may travel the same path to existence, at least according to new findings from the University of Colorado Boulder and collaborators.

This new research, out now in Science, looked at a newly discovered, endangered songbird located only in South America–the Iberá Seedeater–and found that this bird followed a very rare evolutionary path to come into existence at a much faster pace than the grand majority of species.

By comparing this bird to a closely related neighbor (the Tawny-Bellied Seedeater) in the same group (the southern capuchino seedeaters), the researchers determined that genetic shuffling of existing variations, rather than new random mutations, brought this species into existence–and their own behaviors are keeping them apart.

This species is one of only two known examples across the globe to have traveled this path, challenging the typical assumptions of how new species form.

“One of the aspects of this paper that makes it so cool is that we were able to address this question of how the Iberá Seedeaters formed from multiple different perspectives,” said Sheela Turbek, a graduate student in ecology and evolutionary biology (EBIO) at University of Colorado Boulder and the study’s lead author.

“Not only did we collect on-the-ground data on who mated with one another and the identity of their offspring, but we also generated genomic data to examine how similar these two species are on a genetic level. We then zoomed out further to look at where the Iberá Seedeater fits in the context of the broader capuchino