Lifestyle tip: female hummingbirds dress up as males to avoid harassment

In the bird kingdom, it’s usually the males who try to impress the females with their brightly colored plumage. This is also the case with the white-necked hummingbird (Florisuga mellivora): As a rule, females are inconspicuous gray-green in color with white and males steal the show with a shiny blue head, metallic green back and white belly. But this dichotomy isn’t always true for these birds, as it turns out. Some females have the same bright colors as the males.

Two hypotheses

Researchers see two possible explanations, they write in the diary Current biology. Option 1: Brightly colored females are more attractive to males and therefore have a higher chance of offspring. Option 2: Bright colors actually ensure that males bother them less, with the evolutionary benefit that females have more time for useful things like foraging.

Biologists flew to Panama and captured 436 white-necked hummingbirds. Remarkably enough, all of the young birds were brightly colored, including the females. Older females were typically gray or brightly colored like males. This means that many females go through a change as they grow older: from colored to gray. Researchers are uncertain whether this phenomenon is genetically determined, a choice of the bird itself, or the result of environmental factors.

In any case, according to biologists, it is an argument in favor of the hypothesis of sexual harassment. Young birds that have not yet reproduced are of no use if males like their colors – it is better to confuse them with a male and leave them alone.

Video footage and an experiment with female hummingbirds stuffed in their two forms provided conclusive evidence that gray females were harassed more often than brightly colored females. Think about aerial chases, pecking feathers, and even the occasional wrestling match. If a woman “dresses” as a man, she is not immediately recognized as a partner and she can make her own plan.

Poor energy balance

Martijn Hammers, an ecologist at Aeres Hogeschool in Almere and not involved in the hummingbird study, agrees with the finding of the new research. “Hummingbirds have a poor energy balance, they have to eat non-stop to stay alive. If a female is harassed all the time, she will not have time to eat and this is extremely disadvantageous. ‘

According to Hammers, this research answers a fundamental and evolving question. The ecologist points out that similar behavior is already known from other animals. “The female insects also sometimes adopt the colors of the males to avoid intimidation. The fact that this also occurs in hummingbirds suggests that this intelligent phenomenon may be more prevalent in the animal kingdom ”.