Watching a fringe-lipped bat swooping down to eat a tungara frog will give you a new appreciation for bats as predators. It will also give you a new appreciation for how much male frogs want to mate.
Researchers at the University of Texas at Austin filmed multiple views of bats coming down and ripping frogs out of the water. It’s impressive that a bat can not only make a dive like this, but wrestle a creature the size of its own head out of the water while remaining airborne.
It’s not as impressive, though, as the frogs’ willingness to sit in the water making noises specifically designed to call animals close while a predator like that is out there in the night, taking shots at them. The fact that male frogs are doing this in the water makes it even more dangerous. You’ll notice the frog isn’t calling out in these videos. They’ll stop if a bat is close. The ripples they’ve created in the water, specifically to call a mate to them, won’t stop. The frogs have created ways for animals to find them in the water, even when they’re not calling out, and the bats take full advantage of that.
To add insult to, well, death, female frogs have recently been shown to be unable to make the best choice—the frog with the fastest call. According to the summary of one study also done at the University of Texas:
We tested female frogs with three simulated males who differed in relative call attractiveness and call rate. In binary choice tests, females’ preferences favored stimulus caller B over caller A; however, with the addition of an inferior “decoy” C, females reversed their preferences and chose A over B. These results show that the relative valuation of mates is not independent of inferior alternatives in the choice set and therefore cannot be explained with the rational choice models currently used in sexual selection theory.
Tough break, frogs. Bats, congratulations on the meal.