Date: November 4, 2015
Source: McMaster University
The evolution of male songbirds as the colorful consorts of drab female partners is more complicated than long thought, says a McMaster researcher on a team that looked at nearly 6,000 species for a massive study published in the journal Nature.
Conventional wisdom has held that in many species, male birds were more colorful because they were competing for female attention, and that female birds were less colorful because they needed camouflage while guarding their nests.
Now advances in computing power and new methods that compare coloration in different species have allowed the researchers on the study to look at every species of passerine, the perching songbirds that make up about 60 per cent of the world's 10,000 species of birds.
The study offers impressive new evidence that supports some old theories while setting others to rest, explains Cody Dey, an author of the Nature paper who was completing his PhD in Biology at McMaster at the time of the research.
The question of plumage colour is significant, Dey, explains, because birds, especially males, give up so much to look so good, creating an evolutionary mystery that asks exactly what they gain in return for rendering themselves more vulnerable to predation. "These are the questions that have been asked since the start of ecology," he says.
Among the ideas the research supports is that females would have evolved to be even more different than males than they already are, except that every female inherits the genetic material of a colorful male -- an ancestry that is impossible to shake. "If colorful males do better, they're going to produce colorful daughters as well, even though it's not necessarily advantageous for the daughters," Dey says.