These insects give off major red flags

Nature comes in wild colors, like the electric blue tarantulas and brightly spotted poison dart frogs. Named after bull fighters, matador bugs (Anisoscelis alipes) are known for vibrant flag-like red decorations on their hind legs. These insects are native to Colombia, Costa Rica, Ecuador, Panama, Venezuela, and Mexico, and scientists have been stumped as to what their signature red flags on their legs are used for. A study recently published in the journal Behaviors Ecology found that this fancy leg waving is actually part of the matador bug’s elaborate defense strategy.

In animals, some of the most obvious and showy traits are usually expressed by males, like an elk’s large antlers or a peacock’s loud plumage. A 2022 study suggested that matador bugs’ leg movements were not a sexual display. Both male and female matador bugs like to flaunt their removable hind legs and the waving behavior did not change if there were potential mates around or not. It led researchers to question if their leg waving warns predators about a potential chemical defense and bad flavor or divert attacks towards their removable hindlegs to increase their chances of getting out alive.

[Related: Cicadas pee in jet streams like bigger animals.]

To try to answer what is going on with their legs, the team on the new study worked in Gamboa, Panama, a small town near the Panama Canal. They attached red flags that mimicked the matador bug’s accessories to the legs of crickets, and observed how predatory birds called motmots responded to the red flags. Motmots are large birds with iridescent feathers, long tails, keen eyesight, and a strong taste for crickets. The team spent about a month just catching the birds for the experiment.

“We placed the nets in areas of the forest where we saw that the birds moved the most and, when an individual was captured, it was immediately taken to the cages and tested,” study co-author and a research associate at the Smithsonian Tropical Research Institute (STRI) Jorge Medina said in a statement. “When the birds were finished with the tests, we released them back in the same area where they were captured.”