Study Shows How Even Frogs Make Irrational Mating Choices

"In some in cases irrational decisions can be looked at as the better way to have gone"

Give a female frog two potential mating options—an attractive frog and an unattractive frog—and she’ll pick the attractive frog nearly every time. But all bets are off if you throw in a third, less attractive frog, new research shows.

Researchers evaluated mating calls from male túngara frog for the new study, published this week in the journal Science. The finding adds to a growing body of research suggesting that mating choices don’t follow rational expectations.

Male frogs produce a sound to advertise themselves to potential mates. Female frogs typically responded best to longer calls made at a lower frequency when choosing between two male options. But when researchers added a third option to the mix that performed worse on both metrics, the female frog would often choose the intermediate option.

Study author Amanda Lea, a researcher at the University of Texas at Austin, likened the scenario, known as the “decoy effect,” to the way in which a consumer might behave when purchasing a new car. A customer may opt to buy a cheap car with poor fuel efficiency instead of a more expensive car with good fuel efficiency. But the costumer might reconsider when a salesmen presents a third option that is the most expensive and also has good fuel efficiency. The customer won’t choose the third option, but he might instead choose the second most expensive.