Zombie Birds, Astronaut Fish, and Other Weird Animals

by Becky Crew

  “I’m one of the only animals in the world to frequently engage in oral sex?”

  “Good lord. That’s hardly relevant, Mr. Greater Short-Nosed Fruit Bat.”

  “Yeah, I know. But any excuse to say it out loud.”

  You wouldn’t know it by looking at them, but the greater short-nosed fruit bat is one of the most sexually liberated members of the animal kingdom. This fist-sized, burnt-caramel–colored species has been declared one of the only animals in the world to engage in oral sex—and possibly the only animal in the world, besides humans, to engage in frequent oral sex.

  In 2007, researchers from the East China Normal University and Institute of Zoology at the Chinese Academy of Sciences published a study in Biology of Reproduction reporting that fruit bats are one of the few mammal species that experience menstrual cycles. Two years later, a team of entomologists lead by Min Tan from the Guangdong Entomological Institute in China discovered something similarly unusual about the mating behavior of greater short-nosed bats (Cynopterus sphinx).

  Preferring to keep the company of not one, but a harem, of females, a male greater short-nosed fruit bat will construct elaborate tents from stems and leaves, holding them in place with saliva. Taking 30–50 days to complete, the tents provide shelter for the male and the multiple breeding partners he recruits to defend their food stores and produce offspring.

  Tan’s team set up a group of thirty male and female bats in cages filled with large Chinese fan palms, perfect for tent making, and observed their behavior over a month as various harems were established. They found that while grooming themselves or tending to their palm roost, a male would be approached by a female, who stretches out her wings to reveal their leathery girth. The bats then lick and sniff one another, before the male climbs onto the female’s back using his thumbs to adjust himself into a face-to-back mating posture. With the male keeping a firm grip on the female by holding her wings tightly in place with his thumbs and the scruff of her neck in his mouth, the pair will mate.

  The researchers were surprised to find that during fourteen of the twenty copulations, the females would frequently lower their heads to lick the shaft or the base of the male’s penis, which appeared to encourage penile stimulation, stiffening, and erection. “There was a strong correlation between the total length of time that the female licked the male’s penis and the duration of copulation. Therefore the longer the female licked the penis of her mate, the longer they copulated for,” the team reported. They found that for every one second of fellatio there were approximately six extra seconds of copulation. Regarding the six instances that licking behavior was not apparent, the researchers suggested that the female was mating under duress, because she would evade the male for several seconds.

  According to the researchers, this behavior holds several adaptive benefits for the greater short-nosed fruit bat species. Tan offers four hypotheses to explain its penchant for genital licking. The first and second relate to lubrication and penile stimulation, both of which serve to prolong copulation and assist the successful transmission of sperm to the female. The third hypothesis relates to how mate choice in bats can be influenced by chemical signals. Tan’s final hypothesis relates to the possible prevention of sexually transmitted diseases (STDs) between the sexes. It has been known for some time that bat saliva boasts antibacterial, antifungal, antichlamydial, and antiviral properties, which scientists have in the past tried to incorporate into human medications. Right now, researchers including Robert L. Medcalf from Monash University in Perth are working on a stroke medication derived from the anti-blood-clotting saliva from vampire bats, aptly named Draculin.

  While Tan and his colleagues say that their observations are the first to show regular fellatio in animals other than humans, fellatio is not unheard of in other animal species. In separate studies published in 1995 and 2004 by Dutch primatologist Frans de Waal and Italian primatologist and sociobiologist Elisabetta Palagi, it was found that oral sex was a type of “play behavior” performed by young male and female bonobos, an endangered species of great ape. “In general, many animals may lick genitals before and after copulation, for example, the male of [the] ring-tailed lemur, Lemur catta, often licks the genitals of the female in order to judge whether she is in estrous (ready to mate), and after copulation, he also licks his penis,” Tan and colleagues wrote in PLoS ONE. Similarly, said the researchers, both male and female Livingstone’s fruit bats (Pteropus livingstonii) also licked the genitals of their partners during heterosexual interactions, but it’s unclear whether they actually perform fellatio during copulation. So until further research says otherwise, greater short-nosed fruit bats remain almost peerless in their fondness for fellatio.

  It’s Time to Become Gonads

  DEEP-SEA ANGLERFISH

  (Ceratiidae family)

  BEING AN ANGLERFISH MALE would be the absolute worst. As proud as most males in the animal kingdom tend to be of their genitals, the idea of actually becoming genitals by fusing yourself to your mate is a bit much. Unless you’re an anglerfish male, in which case it’s just something that has to be done. Some people have to be garbage collectors, others have to be genitals.

  The bizarre reproductive habits of deep-sea anglerfish were first described in 1922 by Icelandic fisheries biologist Bjarni Saemundsson, who discovered a large female Krôyer’s deep-sea anglerfish (Ceratias holboelli) with two smaller fish attached to her stomach by their snouts. What Saemundsson didn’t realize was that these tiny fish weren’t young offspring taking nutrients from their mother, but sexually mature males. “I can form no idea of how, or when, the larvae, or young, become attached to the mother; I cannot believe that the male fastens the egg to the female. This remains a puzzle for some future researcher to solve,” he wrote in the journal Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening.

  Three years later, British ichthyologist, ecology, and evolution expert Charles Tate Regan found a similar situation. This time a single small fish was fused to a female, and Tate recognized it not as a mother-offspring relationship, but a parasitic male-female relationship, reporting in Proceedings of the Royal Society B:

  [The male fish is] merely an appendage of the female, and entirely dependent on her for nutrition … so perfect and complete is the union of husband and wife that one may almost be sure that their genital glands ripen simultaneously, and it is perhaps not too fanciful to think that the female may possibly be able to control the seminal discharge of the male and to ensure that it takes place at the right time for fertilization of her eggs.

  Anglerfish belong to an order Lophiiformes, which is a highly diverse group of fish boasting an array of shapes, including elongated, spherical, and flattened bodies, living 985 feet below the surface. There are around 200 species of anglerfish spread around the world’s oceans. Anglerfish in the family Ceratiidae, also known as sea devils, live at depths of 0.6–2.5 miles in the bathypelagic zone where not a speck of sunlight exists. They are famous for the reproductive process that sees free-swimming adolescent males attach themselves to a female and morph into a living, parasitic set of gonads.

  Members of the Ceratiidae family are generally top heavy with relatively large heads and jaws filled with many tiny teeth set into an extreme underbite position. The females of each species are adorned with a bioluminescent lure that extends from their foreheads in myriad shapes, sizes, and lengths. Characteristic of the Ceratioidea is their extreme sexual dimorphism, which describes a genetically determined difference between males and females of the same species expressed by their morphology, behavior, or ornamentation. In birds, sexual dimorphism is the difference between the stunningly beautiful male peacock and its drab female counterpart, and in the Ceratioidea’s case, this means large females and significantly dwarfed males. So dwarfed are the deep-sea anglerfish males, measuring an average of just 0.2–0.4 inches in their free-swimming, adolescent stage, that they are one of the world’s smallest vertebrates. In the most extreme cases, such
as the Krôyer’s deep-sea angler- fish, the females can be up to sixty times larger than the males, more than 3 feet in length, and half a million times heavier.

  While Ceratioidea males lack the female’s bioluminescent luring apparatus, which is formed by the foremost three spines on her first dorsal, or back, fin, they do have large, well-developed eyes and gigantic nostrils in their adolescence. Researchers have suggested that these are used for homing in on a special hormone emitted by the females. When a male finds a female, it will start to metamorphose, its eyes and nostrils degenerating while its teeth are replaced by large pincers. These are used to grip on to a prospective mate, which begins the fusing process of the male’s mouth to the female’s body. Some species see just one male attaching itself to a single female, while in other species a female can host up to eight dependent males. Although it may seem like an unnecessarily complicated process to get the males and females to reproduce, researchers suggest that it is the only way, because without fusing with the females the males will never reach sexual maturity. And likewise, the females will never become gravid, meaning capable of carrying eggs internally, unless they have a male attached. According to American systematist and evolutionary biologist Theodore Wells Pietsch III, one of the world’s experts on anglerfish, “That sexual maturity is determined not by size or age in these fishes, but by parasitic sexual association, may well be unique among animals.”

  Publishing a study in Ichthyological Research in 2005, Pietsch said that in some species of Ceratioidea, the fusing of flesh involves the combination of circulatory systems, which means the males depend entirely on the females for their continued survival, “while the host female becomes a kind of self-fertilizing hermaphrodite.” Pietsch adds that the males increase:

  considerably in size once fused, their volume becoming much greater than free-living males of the same species, and being otherwise completely unable to acquire nutrients on their own, the males are considered to be parasites. They apparently remain alive and reproductively functional so long as the female lives, participating in repeated spawning events.

  Pietsch, who is currently the curator of fishes at the Burke Museum of Natural History and Culture at the University of Washington, has been studying anglerfish for over twenty years. In early 2012, he went to bat for them when a group of scientists, led by Louisiana State University graduate student Eric Rittmeyer, declared a newly discovered species of frog the world’s tiniest vertebrate. Publishing in PLoS ONE, Rittmeyer and his team described Paedophryne amauensis, a copper and black frog from New Guinea averaging just 0.3 inches in length. Pietsch challenged the new frog’s inclusion in the Guinness Book of Records promptly after the paper had been published, arguing that the free-swimming adolescent male of an anglerfish he described in his 2005 paper stretches just 0.24 inches, making it 11 percent smaller than Paedophryne amauensis. But due to the fact that females of the same species are up to six times bigger than the frog, Rittmeyer’s team was not convinced. For now, it looks as though the title of World’s Smallest Vertebrate is subject to opinion.

  Journal Notes: Deep-Sea Anglerfish

  June 3

  I never knew my father. Mother told me as soon as I was old enough to understand that he was gone before I was born. My friends all say the same about their fathers, but it doesn’t make it hurt any less. That he didn’t want to stick around to see what I’d look like, what I’d act like, which college I’d end up going to. So that’s why I’m going to learn everything I can about him, discover what clues he left behind so that I might come to understand who I am and who I will become. Ate lunch, got indigestion like always. Note to self: eat slower.

  June 5

  Questioned Mother while she was making dinner. Got mostly cagey responses but she put chilies in our meal, which she never does, so suspect chili is some kind of clue. Suspect Mother is trying to tell me something. Called the Chili Palace, man on phone didn’t seem to want to talk about anything but chili dogs. Suspect he and Mother are in cahoots. Watched Downton Abbey. Hated it.

  June 6

  Googled Dad. Discovered that he was a tailor and had a shop in town that’s now a comic book store that I can’t go into anymore because I’m in love with the girl who works there. Found photo of my English teacher wearing one of Dad’s Prince of Wales suits while attending a production of Uncle Vanya: The Musical on Sea Morning Herald society site. Googled Uncle Vanya: The Musical, universally panned, but there’s a good chance Chekhov liked chili, so ordered a dog from the Chili Palace. Indigestion.

  June 9

  Just realized something. Got the Chili Palace receipt out of my bin: $4.44. Which corresponds to all Ds in the alphabet. Ds for “Dad.” I’m really onto something here. Showed Mother to see if her reaction would give anything away and she said not to use her credit card again.

  June 10

  Learned about the whole morphing-into-genitals thing in sex ed class today. Contemplating becoming a warlock whatever the male version of a nun is.

  Sexy Monkeys Bathe in Urine

  CAPUCHIN MONKEY

  (Cebus)

  SO, MONKEYS COAT THEMSELVES in urine to become more attractive to the opposite sex. Not exactly surprising, seeing these are the same animals that love a good spot of public masturbation.

  Of the New World group of monkeys, which includes squirrel monkeys, marmosets, howler monkeys, capuchins, and tamarins, a number of species are known to wash themselves in their own urine by urinating into their hands before vigorously rubbing them all over their feet and fur. Many hypotheses have been proposed to explain the behavior, such as thermoregulation—the urine cools them down—communication between rivals, communication during sexual encounters, and recognition of other individuals of the same species via their scent, but for years no one was able to come up with conclusive evidence one way or another.

  Primatologist Kimberley Phillips from Trinity University in San Antonio, Texas, decided to peer into the minds of these curious primates to find out what information the signals in their brains could provide. “I was at the zoo one afternoon, observing monkeys, and just thinking about their behavior,” says Phillips. “It was one of those ‘aha’ moments, especially when I realized we could use brain imaging to assist in solving this puzzle.”

  Capuchin monkeys belong to a genus of over twenty species ranging over tropical and subtropical South and Central America, including Peru, Bolivia, and Brazil. Depending on the species, capuchins can be black, brown, burnt caramel, or cream, with their nude pink faces peering out of their soft, dense fur. They are relatively small, never growing over 11 pounds, and agile, built to spend their days hopping between trees, using their long, slender tails for grasping and balance. When the females are sexually receptive, they will actively solicit a male, and previous studies had shown that when this happens, the selected male will step up his urine washing. “Every capuchin I’ve seen—in the wild and in captivity—has engaged in this behavior at some point,” says Phillips.

  She tested the reactions of a group of captive-born female tufted capuchins (Sapajus apella) to urine collected from both adult and juvenile males. Using magnetic resonance imaging (MRI) scans, she was able to detect the activation of regions in the brain associated with smell and sexual behavior in the females far more when they sniffed the adult males’ urine than when they sniffed the juvenile males’ urine. Because the sexually mature males provoked the greater response in the females, Phillips reported in a 2011 issue of the American Journal of Primatology that she had found conclusive evidence that at least one of the functions of urine washing was sexual communication. “I wasn’t surprised that urine washing served a role in sexual communication, as this type of pheromonal communication occurs in a variety of other species; but I was a bit surprised that the neuroimaging results turned out so nicely,” she says. “But we did not discount other functions of this behavior. It is likely that there are other communicative and other functions as well.”

  The Capuchin Monke
y’s Guide to Getting Laid

  Hi guys, a lot of you have been asking me for some dating advice because I dated a Kardashian that one time, so I’ve decided to post a little dating guide here so all you losers actually have a shot.

  Lunch Date

  Lunch dates are pretty noncommittal and depending on the rate of service at whatever establishment you choose, you can usually get it over pretty quickly if you decide halfway through you’re not that interested in her after all. When you’re getting ready to go, make sure you choose a fairly casual outfit; you can get away with being too casually dressed if you’re witty or pretending to be a scruffy shipping heir, but you can never come back from accidentally trying too hard with your clothes. Grab your keys, wallet, and phone, pee on yourself, head out the door.

  The same pretty much goes for dinner dates, except add flowers, plus you can get away with applying a little bit more pee.

  Hot New Girl’s First Day in Your Office

  Make friends with the IT guy who can see her desk from his and get him to tell you when she’s heading toward the kitchen for tea or something. Pee on yourself. Meet her in the kitchen and tell her about how you prefer Lady Grey because then she’ll think you have sophisticated taste buds.

  In the Club

  Shots, pee on yourself, shots, repeat.

  Next week: my guide to picking the right kind of suit for every occasion.