Female cave insects of the genus Neotrogla have elaborate, penis-like organs called gynosomes. (Credit: Yoshizawa et al, Current Biology)

Female cave insects of the genus Neotrogla have elaborate, penis-like organs called gynosomes. (Credit: Yoshizawa et al, Current Biology, via Cell Press)

Researchers have discovered four related species of cave insects in the genus Neotrogla in which females have evolved an elaborate, penis-like organ known as a gynosome. By contrast, males have a much reduced, vagina-like opening, through which they provide nutritious seminal gifts in addition to sperm. Because of the resource-poor environment of the cave, it’s advantageous for females to mate at a higher rate; the researchers speculate that this situation may have driven the evolution of the unusual mating system.

Original research paper published in the journal Current Biology on April 17, 2014.

Names and affiliations of selected authors

Kazunori Yoshizawa, Hokkaido University, Japan

Rodrigo Ferreira, Federal University of Lavras, Brazil