Male paper wasps appear ridiculously good-looking (at least to female wasps) if they have large black face spots and yellow abdominal splotches. Male wasps with these bigger spots have better luck at mating, according to Brazilian scientists in their recently published paper “Sexy Faces in a Male Paper Wasp.”
To figure out the importance of a sexy insect face, the researchers placed two male wasps in a glass box with a female, and let the wasps do their thing. In 10 out of 44 encounters, a female wasp mated with a male. These males almost always had more black and yellow colorings than the unsuccessful bugs. (Waspy rejection stung: female wasps, which are larger and more aggressive, will bite or sting the males that make unwanted advances.)
[Male paper wasps (top, A-E) show a variety of black markings on their heads. Females for comparison along the bottom row (F-H). Image credit: de Souza et al.]
Sexual signals, the scientists write, “provide useful information to the receiver.” Because a female wasp needs to store sperm in her body over winter months, picking a good quality mate -- indicated, in part, by his attractive face -- is an important part of laying healthy eggs.