Ever wonder what might make one species split in two? A new study in the journal Current Biology shows that it could come down to a simple female preference for a specific type of buzz.
Red mason bees are small solitary bees that are common across Europe, but females prefer to mate locally. Male bees from Germany and the UK will try to mate with any female they meet, but German females aren't interested in British males, and British females spurn German advances. But it wasn't clear how the females figured out where the males were from.
Entomologists Taina Conrad and Manfred Ayasse of the University of Ulm in Germany thought that the males from each region might be speaking a different language. Male red mason bees vibrate when they mount a female, and females were thought to choose the males who could vibrate longest. But when Conrad and Ayasse used small magnets to change the vibration pattern of male bees to match bees from another region, they showed that females are actually looking for more than just a strong buzz.
When English males were allowed to use their natural vibration pattern with English females, the females let them mate. But when their vibrations were switched to the German pattern, English females just weren't as interested. German females, on the other hand, went wild. The same pattern prevailed with the German males when they were given a British sound.
Female red mason bees are still choosing males with long, strong vibrations, but they also prefer to mate with males who speak their native vibrational language. That preference, write Conrad and Ayasse, might eventually split their one species in two.
Image by Taina Conrad