Dark Banquet - Bill Schutt [10]
In 1801, in Paraguay, the Spanish cartographer and naturalist Felix D’Azara collected the creature that would eventually become known as the common vampire bat. But even though D’Azara asserted that this was the bat responsible for attacks on humans and livestock, British and French taxonomists thumbed their noses at his claim. In 1810 the same bat was named and described by Geoffroy. Desmodus (literally, “fused tooth”) was named for its unique incisors: a chisel-shaped set of uppers and a uniquely bi-lobed pair of lowers. Unfortunately, there was absolutely no mention of blood feeding in Geoffroy’s description of Desmodus. Similarly, in 1823 Spix named and described a bat that had been collected in Brazil, but it would be years before Diphylla ecaudata would be recognized as a second vampire bat species.*12
It wasn’t until 1832, when Charles Darwin and his servant observed Desmodus rotundus feeding on a horse, that the English-speaking world had a name to associate with the blood-feeding deed.
The vampire bat is often the cause of much trouble by biting the horses on their whithers. The injury is generally not much owing to the loss of blood as to the inflammation which the pressure of the saddle afterwards produces. The whole circumstance has lately been doubted in England; I was therefore fortunate in being present when one was actually caught on a horse’s back. We were bivouacking late one evening near Coquimbo, in Chile, when my servant, noticing that one of the horses was very restive, went to see what was the matter, and, fancying he could detect something, suddenly put his hands on the beast’s whithers, and secured the vampire.*13
(Charles R. Darwin)
Because of similarities in appearance, behavior, and range (parts of Mexico, the warmer regions of South and Middle America, plus the islands of Trinidad and Margarita), Desmodus, Diaemus, and Diphylla were initially placed into their own family, the Desmodontidae. More recently, researchers have reduced them to a subfamily within the large, primarily Neotropical family Phyllostomidae. There are around one hundred and fifty phyllostomids (i.e., members of the family Phyllostomidae) and they’re sometimes referred to as New World leaf-nosed bats. This is because they live in the Americas and most of them have a vertically projecting, spear-shaped nasal structure. Although nose leaves may look menacing, they are actually soft and pliable.
Early naturalists claimed that nose leaves were used by vampire bats as deadly flesh stilettos, to gouge victims before a blood meal. Many years later, scientists studying the strange ultrasonic capabilities of bats uncovered an interesting, though decidedly less gory function for the nasal protuberances. Just as a megaphone can be used to direct the human voice, the nose leaf is actually involved in directing the echolocation calls emitted by the bat. Ironically, nose leaves are greatly reduced in size in vampire bats (like Desmodus) where they function primarily in thermoperception—the ability to sense differences in temperature. This is an adaptation that comes in handy as vampire bats approach their warm-blooded prey in complete darkness. Once the bat gets within around fifteen centimeters of its target, thermoreceptors in the low, ridgelike nose leaf can detect the slight temperature differences that exist in areas of the skin where blood vessels lie just below the surface. The