Because we can walk and talk and have conscious thought, humans tend to forget that in essence, we’re animals. Sure, most of us have somewhat refined our more beastly behaviors, but the biological imperative is strong among all living things, and we’re all connected. Take, for instance, the results of a recent study that shows female frogs fake their own death to avoid unwanted attention from males. If that’s not relatable, I don’t know what is.
- Researchers were studying the European common frog. Their study, which was published in the Royal Society Open Science journal, found that instead of dealing with the fact that male frogs can be extremely sexually aggressive — they sometimes cling so hard to the female that they end up killing her — the females have come up with an ingenious solution.
- Female frogs aren’t simply passive creatures. As Dr. Carolin Dittrich, the lead author of the study performed by the Natural History Museum of Berlin, writes: “It was previously thought that females were unable to choose or defend themselves against this male coercion … Females in these dense breeding aggregations are not passive as previously thought.”
- How did scientists figure this out? The study saw Dittrich and co-author Dr. Mark-Oliver Rödel placed male frogs one by one into a box with two females, a small one and a large one. They then recorded the mating behavior that took place and found that of the 54 females tested, 83% tried to rotate out of the male grasp, with 48% making “release calls.” Roughly 33% exercised tonic immobility in which they made their arms and legs go stiff to “play dead.” In fact, the smaller females tried all three methods.
- This isn’t the first time this behavior among frogs has been noted. According to Dittrich, one scientist mentioned tonic immobility back in the 18th century, though no one paid much attention at the time. “I found a book written in 1758 by Rösel von Rosenhoff describing this behavior, which was never mentioned again,” she said.
- Researchers believe tonic immobility may be a stress response. Since it was more common in the smaller, younger female frogs, they could be experiencing more trauma when male frogs try to mate with them as they are less experienced.
- Further studies are needed to figure out the implications of this finding. “In the real world we often observe the formation of mating balls, but also that females can more easily dive away because there is more structure and places to hide,” she said. Mating balls are when multiple male frogs pile onto a female to duke it out for a chance to reproduce. “I think even if we call this species a common frog and think we know it well, there are still aspects we don’t know and perhaps haven’t thought about,” she added.
- Frogs aren’t the only animals who fake their death to avoid male attention. Female dragonflies also fake their own death to get away from aggressive males. We might want to take a note from the animal kingdom!