Fruit flies in the Drosophila buzzatii cluster can generally be found in South America, living in arid environments and dining on fermenting cacti (yum!). Although their lives may sound like a simplistic paradise, they wouldn’t have stuck around for this long if it wasn’t for the females’ ability to pick the right mates.
According to a new study published in the open-access journal PLOS ONE by Patricia Iglesias and Esteban Hasson of the University of Buenos Aires, Argentina, female Drosophila buzzatii fruit flies may be drawn to the specific courtship songs of males of their own species.
Male fruit flies in this cluster vibrate their wings to attract females, producing a distinct diversity of courtship songs. The researchers analyzed the role of courtship songs in female mate choice for four of the species in the D. buzzatii cluster, as well as one species in the D. martensis cluster that was used for comparison.
The study involved exposing female flies to wingless, silent males and observing their copulation choices during either silence, playback of courtship songs from their own species, or playback of songs from a different species. The researchers discovered that females from three of the species in the D. buzzatii cluster use courtship songs to ensure they pick mates of the same species, while one species in this cluster used the courtship songs as a way to rank mates.
Female flies from the “same mate” species would only copulate with male flies during the playing of courtship songs from their own species, while females from the “ranked mate” species would reject males even while their own species-specific courtship song was being played. Neither of these effects were seen in the D. martensis cluster species.
The study also explains that the influence a courtship song had on mate choice tended to vary between individual females, so future research may be aimed at determining why females vary in their preferences and behavior.
Despite these differences, the overall data collected shows that D. buzzatii cluster females do use courtship songs to assist them in choosing a mate, with most preferring songs produced by their own species. The researchers believe that these female preferences could be an important factor in diversification and speciation within the D. buzzatii cluster.
Image Credit: Iglesias et al (2017)