Male German cockroaches (Blattella germanica) offer females a pre-mating “gift” of body secretions that combines sugars and fats – think of the roach version of chocolate – in order to attract and hold female attention long enough to start copulation.
“This is common mating behavior in insects and some other animals: males present females a tasty or valuable gift – it’s like Valentine’s Day, but every day,” said Coby Schal, Blanton J. Whitmire Distinguished Professor of Entomology at NC State and co-corresponding author of the paper.
The study shows, however, that females averse to the simple sugar glucose get an unpleasant surprise when they mix their saliva with the male secretions – saliva degrades the sweet treat of complex sugars to glucose, which becomes a bitter pill that ends the courtship ritual, with the female scurrying away without mating.
“We’re seeing glucose-averse female German cockroaches turning down this nuptial gift – and the chance to mate – and wanted to understand more about the mechanism behind it,” said Ayako Wada-Katsumata, principal research scholar at NC State and co-corresponding author of the paper.
The study appears in Nature Communications Biology. Postdoctoral scholar Eduardo Hatano, Ph.D. student Samantha McPherson and Jules Silverman, Charles G. Wright Distinguished Emeritus Professor of Entomology, co-authored the paper. The research was supported by the National Science Foundation under grant IOS-1557864, the U.S. Department of Housing and Urban Development Healthy Homes program (NCHHU0053-19), and the Blanton J. Whitmire Endowment at NC State.