Dark Banquet - Bill Schutt [9]
I looked over at Farouk, who nodded and motioned toward the stairwell. “We’d better get going, Bill. We don’t want to be out here after dark.”
“Second that,” Janet said.
I turned to say something to my wife, but she was already moving toward the exit.
“Right,” I said, following the beam from Janet’s headlamp as she sought the comfort of sunlight.
Like nectarivory, blood feeding in bats is another highly specialized lifestyle, but there is little or no convergence between birds and bats, in all likelihood because there’s no competition between the two groups. While there are birds that regularly feed on blood (e.g., vampire finches and, indirectly, those that pick ectoparasites like ticks off of large mammals), none of these birds is an obligate blood feeder like the vampire bats. In other words, no bird species will starve to death in two or three days if it doesn’t secure a blood meal. This means that as far as vertebrate sanguivores are concerned, bats hold the exclusive rights to their aerial and terrestrial niches.*10
So what did the early naturalists have to say about vampire bats, and how did these creatures become forever tied to the growing vampire hysteria that was simultaneously taking place in Europe? How did blood feeding evolve in bats, and why has it never appeared in birds—an older and more diverse group? Oh, and finally, why is just about everything people think they know about vampire bats completely wrong?
It might be best to start with this last question.
Can you tell me why in the Pampas, ay and elsewhere, there are bats that come out at night and open veins of cattle and horses and suck dry their veins; how in some islands of the Western seas there are bats which hang on the trees all day, that those who have seen describe as giant nuts or pods, and that when the sailors sleep on the deck, because that it is hot, flit down on them—and then in the morning are found dead men, white as even Miss Lucy was?
—Bram Stoker
2.
CHILDREN OF THE NIGHT
When the explorers of the New World returned home to Europe in the fifteenth and sixteenth centuries, they were far more concerned with gold, God, and geography than they were with accurate zoological accounts. Amid fanciful tales of sea serpents, giants, and mermaids, there were also reports of bats that fed at night upon the blood of unfortunate humans and their livestock. Although these creatures were generally described as being hideous, with wingspans of up to five feet, nobody actually took the time to figure out which bats were vampires and which weren’t. The rule of thumb seemed to be that the largest and ugliest bats were vampires—and, on both accounts, the explorers were dead wrong.
Early taxonomists contributed significantly to the confusion. Carl von Linné (who actually Latinized his own name) and the morphologist Étienne Geoffroy Saint-Hilaire were responsible for initiating a misunderstanding regarding bats and blood feeding that still exists today. With little knowledge of the bat’s biology and no regard for their actual diet, they assigned scientific names like Vampyrum spectrum (which happens to be a really large bat), Vespertilio vampyrus, Vampyressa, and Haematonycteris to bats that had never so much as snuck a sip of blood.*11
Even card-carrying tropical zoologists got things horribly wrong. Johann Baptiste von Spix, curator of the zoology collection at the Bavarian Academy of Sciences, had spent nearly three years on a collecting trip to Brazil starting in 1817. He returned with thousands of specimens, many never before seen in Europe. One of these was Glossophaga soricina (the pollen-dusted bat I had “swoop-netted” at Wallerfield). Spix described Glossophaga as “a very cruel blood-sucker” (sanguisuga crudelissima), hypothesizing that the creature we now know to be a delicate hummingbird mimic actually used its brushlike tongue tip to reopen the wounds it had somehow inflicted with its tiny teeth.
The chiropteran disinformation campaign continued well into the nineteenth century. By this time