A Face for Feasting
The shape of a bat’s head suits its dietary food habits. They can be nectar feeding (plants), insectivorous (eats insects), frugivorous (eats fruits), carnivorous (flesh eating), omnivorous (wide-ranging foods) and hematophagous (feeding on blood). The fruit bat, for example, has a long snout and a long tongue to sip nectar and eat fruits.
Some bats catch frogs, small birds or mice, but the vampire bat of Central and South America can take a little bite on a cow, for instance, and lick up the blood. Substances such as a natural anticoagulant in the bat’s saliva keeps the cow’s blood flowing. Since blood is quite diluted, the bat needs large amounts for its size in order to reap nutritional benefits. Consequently, vampire bats’ stomachs and kidneys rapidly separate the water from the rest of the blood and the bats can become engorged and unable to fly.
Weighing just one or two ounces, this tiny bat does not hurt the victim. One ounce of blood is usually enough for two or three days. In addition, the bat will share this meal with a sick or hungry member of its colony. The downside is this makes them susceptible to blood-borne diseases such as rabies—an infectious disease that affects the central nervous system—that can be passed on to other animals and humans and can be fatal, although they very rarely attack humans.