Vampire Origins

Vampire bats are the only mammals that survive entirely by feasting on blood. This red liquid is rich in the metal iron (Fe) and protein. But it’s low in other nutrients, such as fats and carbohydrates, that mammals need to live.

A team of scientists wanted to know how vampire bats came to survive on such an odd diet. The group compared the genetic makeup of the common vampire bat with that of 28 other bats that don’t drink blood. The researchers discovered 13 genes, or units of hereditary material, that no longer work in vampire bats. Some of these broken genes aren’t a defect but an adaptation, says Michael Hiller, an evolutionary biologist at the Max Planck Institute in Germany. Without these genes, the bats gained new abilities. For example, they are able to conserve the sugar in their body and process high amounts of iron.