Wild vampire bats in Brazil that are believed to exclusively feed on bird blood have started to feed on human blood by night.
Better Adapted At Processing Bird Blood
The hairy-legged vampire bat, Diphylla ecaudata, which lives in northeast Brazil typically targets large birds to feed on at night time.
The bats primarily feed on birds because they have evolved to be better at processing bird blood, which is characterized by high levels of fat, than at digesting the thicker and high-protein blood of mammals. The nocturnal animals would suck a spoonful of blood from one animal as meal.
Earlier experiments have shown that many of the bats would opt to fast and starve to death when only pig and goat blood was available.
Enrico Bernard, from the Federal University of Pernambuco in Recife, Brazil, and colleagues, however, have found evidence suggesting that the bats have started to eat something that is outside of their traditional diet.
Traces Of Human Blood In Fecal Samples
Bernard and colleagues analyzed fecal samples from a colony of the hairy-legged vampires that live in Catimbau National Park in northeast Brazil. The researchers found that of the 15 samples that they managed to get DNA from, three had traces of blood from humans, suggesting that the animals have started to suck on human blood...