{"id":70405,"date":"2023-10-27T13:58:07","date_gmt":"2023-10-27T20:58:07","guid":{"rendered":"https:\/\/in.nau.edu\/news\/?p=70405"},"modified":"2023-10-30T08:26:59","modified_gmt":"2023-10-30T15:26:59","slug":"vampires-bats-and-vampire-bats","status":"publish","type":"post","link":"https:\/\/in.nau.edu\/news\/vampires-bats-and-vampire-bats\/","title":{"rendered":"Vampires, bats and vampire bats"},"content":{"rendered":"

Halloween and horror movies are filled with creatures designed to strike fear in the hearts of viewers\u2014from those that drink blood in the night to insects that grow too large and develop a taste for human flesh and aliens that cross the universe intent on the destruction of humanity. But is there any truth behind any of these fantastical creatures? Turns out, the answer is yes, though the real deal is much more nuanced\u2014and much more intriguing\u2014than their Hollywood doppelgangers.<\/em><\/p>\n

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Common vampire bats (<\/em>Desmodus rotundus). They’re cute if you keep your distance.<\/em><\/figcaption><\/figure>\n

Vampires may not be real, but there are plenty of creatures that would drink your blood if given the chance. Vampire bats, however, hold a unique place in our imagination despite presenting little risk to humans\u2014far less than disease-carrying mosquitoes and ticks (and far less scary of a prospect than bedbugs, if I\u2019m honest). The only blood-drinking mammal, vampire bats live in Central and South America (not Arizona) and it\u2019s rare that they drink human blood.<\/p>\n

Faith Walker<\/strong>, a research professor and director of genetics of the Bat Ecology & Genetics Lab<\/a> and the Ancient DNA Lab<\/a> in the School of Forestry, said vampire bats were likely the first blood donors. They can also live a long time and a carry a grudge\u2014more on that later.<\/p>\n

Females of\u00a0Desmodus rotundus<\/em>, one of three vampire bat species, form daytime roosting groups of between 20 and 100 individuals.\u00a0When a bat comes home hungry, as do about one-tenth of adults and one-third of juveniles, a roostmate will kindly provide a meal of regurgitated blood.\u00a0Youngsters, who without food perish in a few days, are particularly prone to hunting failure because they lack the considerable skill required to painlessly extract blood.\u00a0When hunting, a bat follows its heat-sensing noseleaf to prey\u2014primarily cattle\u2014where it lands and crawls hoofward.\u00a0The bat licks and cuts the bite site, a process that takes 20 minutes, then must remain unnoticed for the time needed to drink half its body weight in blood.\u00a0This clandestine act is aided by a salivary anti-coagulant dripping down the tongue\u2019s top into the wound, which keeps blood flowing, and by grooves on the tongue\u2019s underside that serve as drinking straws. (That anti-coagulant is called\u2014what else?\u2014Draculin.<\/a>)<\/p>\n

Females of this South American species have a high survival rate and can live to be 18 years old, which results in individuals spending a long time together.\u00a0Their system of reciprocal food sharing works because they can recognize each other.\u00a0This ability is facilitated by social grooming: prior to donating or receiving blood, a pair vigorously grooms one another, revealing their identities by distinctive vocalizations.\u00a0During grooming, a hungry bat pats the swollen belly of a roostmate, prompting a lengthy regurgitation.\u00a0Later, after a successful hunt, the recipient is more prone to donate and prefers to feed the bat that recently gave blood.\u00a0Females that attempt to cheat the system by receiving but not donating are remembered and refused when hungry.\u00a0This is one of the few species in which reciprocity exists between both related and unrelated individuals, a characteristic that may have evolved during the ecological bottleneck created by the disappearance of their main prey\u2014the large herding mammals\u2014at the end of the Pleistocene Era.<\/p>\n