A study suggests that female hummingbirds are similar to males to avoid bird attacks

They may roam cute and sociable in appearance, but the hummingbird world is full of aggression. Now some female hummingbirds seem to have evolved to avoid this – by adopting the lustrous feathers of their male counterparts.

US researchers have captured more than 400 white-necked Jacobin hummingbirds in Panama.

Surprisingly, they found that more than a quarter of the females had ostentatious plumage similar to the males – iridescent blue heads, crisp white tails and white bellies. Typically, female Jacobites tend to be fainter by comparison, waving muted green, gray or black hues that allow them to blend into the environment.

Experiments conducted by the researchers indicated that flashy clothing resembling a male costume helped females avoid aggressive male behaviors during feeding, such as clicking and hitting the body.

When the researchers examined the captured birds, they found that all young or juvenile Jacobites showed bright colors. In general, in most species of birds, juveniles usually resemble the opposite sex of adult birds.

“So, it was clear that something was at play,” said the study’s first author, Guy Falk, who is now a postdoctoral researcher at the University of Washington but who led the research as part of the Cornell Lab of Ornithology and the Smithsonian Tropical Research Institute. .

Every male and female begins to look like an adult male. Then as they get older, about 20% of the females retain these feathers, and then 80% of them turn into monotonous feathers.”

It is generally believed that the bright ornamental plumage of many species evolved as a function of competition for mates. But in this case, most females weren’t keeping these colorful plumage when they were sexually mature and looking for mates, a hint that so-called sexual selection wasn’t the cause, he pointed out.

Falk and colleagues attempted to answer why some Jacobite females continue to resemble males as adults by leaving stuffed hummingbirds on feeders (males, females and poor males) and watching real hummingbirds interact with them at various locations in Panama.

They found that most of the sexual behavior of what appeared to be true male hummingbirds was directed at pale, stuffed females, reinforcing the idea that sexual selection was not the correct explanation, according to A study published in the journal Current Biology.

However, when they looked at the aggressive actions between stuffed and real hummingbirds, the researchers found that dull stuffed females were more often attacked than shiny stuffed females. “This species gave us an indication that it has to do with social selection and competition for food, rather than competition for mates,” Falk said.

In general, people believed that hummingbirds are little fairies that drink the nectar of flowers. “But they fight constantly…Aggression is a big part of their lives.”

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