The “whispering” bats are a diverse population that eat a variety of different foods. But what led to this amount of diversity in their diet?

Laurel Yohe, a graduate student in the Department of Ecology and Evolution working with professor Liliana M. Davalos, studies this family of bats in the present as well as their ancestors from the past in an attempt to answer this question.

“We are slowly figuring out which resources were available when this species was evolving,” Yohe said. “You have all these different species, but something led to this huge variation in diet, and this gives us a hint of what resources were available that then they were able to stop feeding on insects or early on start to incorporate different food into their diet and then slowly start to specialize into what their diet is now.”

Through the use of a single molar tooth, a model was developed that predicts a range of what the skull size and shape was, as well as what the bat most likely ate.

“A tooth is the jackpot,” Yohe said. “You can learn so many things from it—you can learn about the diet, and you can estimate the skull size.”

This provided the evidence that the bats at this time were omnivorous—eating both plants and animals. Instead of eating only one type of food, these bats were able to eat a diverse diet. This provides a link to the whispering bats’ diversity that Yohe studies. Yohe developed the mathematical model that was used to understand this bat and its diet.

“With the nectar feeding fossil, it gave us an insight into an ancient transition from eating insects, which most bats do, to exploiting all these different resources in the tropics,” Yohe said. “And so, my research specifically focuses on this group of bats that are only found in south and central America and essentially eat almost anything under the sun—a group of 200 bats, and there are some that eat fruit, and some that eat nectar, and some that eat blood, like the vampire bat, and frog eating bats and small vertebrate, mouse eating bats, and insectivores and omnivores, which is everything in between.”