Chapter 8. Hormones and Sex
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By Jesse Singal Those who advocate for sound, evidence-based research about autism are extremely alarmed about Donald Trump, and for good reason: In addition to Trump’s ties to Andrew Wakefield, the disgraced British doctor whose debunked research helped fuel the false idea of links between childhood vaccines and autism, Robert F. Kennedy Jr., a notorious anti-vaxxer himself, told reporters back in January that Trump planned to tap him as chair of a commission on “vaccine safety.” There is no question at this point that Trump has significant connections to a pseudoscientific medical movement that spreads dangerous, disproven ideas. Today, Trump gave nervous observers yet more reason to worry. It occurred at a White House event in which Trump and Secretary of Education Betsy DeVos met with a bunch of educators. Trump seemed to fixate, for a moment, on one educator named Jane (her last name is hard to make out) after she explained that she is the principal of a special education center in Virginia. The sequence starts at about 5:38 in this video: After Jane noted that many of her students have autism, Trump asked, “Have you seen a big increase in the autism, with the children?” Jane replied in the affirmative, but seemed to couch her response as being more about an increase in demand for services — she didn’t explicitly agree there’s been a big increase in the overall rate. Trump continued: “So what’s going on with autism? When you look at the tremendous increase, it’s really — it’s such an incredible — it’s really a horrible thing to watch, the tremendous amount of increase. Do you have any idea? And you’re seeing it in the school?” Jane replied — again, in a way that seems a bit noncommittal vis-à-vis Trump’s claim — that the rate of autism is something like 1-in-66 or 1-in-68 children. To which Trump responds: “Well now, it’s gotta be even lower [presumably meaning higher, rate-wise] than that, which is just amazing — well, maybe we can do something.” (Jane had the rate right, and Trump is incorrect that it has crept higher.) © 2017, New York Media LLC.
Link ID: 23233 - Posted: 02.15.2017
Elizabeth Eaton A prehistoric marine reptile may have given birth to its young alive. A fossil from South China may be the first evidence of live birth in the animal group Archosauromorpha, scientists report February 14 in Nature Communications. Today Archosauromorpha is represented by birds and crocodiles — which both lay eggs. Whether this fossil really is the first evidence of live birth in Archosauromorpha depends on how another group of semiaquatic animals is classified, says Michael Caldwell, a vertebrate paleontologist with the University of Alberta in Canada. Placement of Choristodera, a now-extinct group that included a freshwater reptile that gave live birth, remains murky, with some researchers putting them with Archosauromorpha and others with a group that includes snakes and lizards. “Our discovery is the first of live birth in reptiles with undoubted archosauromorph affinity,” says Jun Liu, a paleontologist at Hefei University of Technology in China. Researchers have speculated that the biology of archosauromorphs prevented their reproductive traits from evolving, says study coauthor Chris Organ, an evolutionary biologist with Montana State University in Bozeman. This find may disprove that view. “Ancestrally, the science suggests that live birth is not absolutely prohibited,” Organ says. Even though birds and crocodiles haven’t yet evolved to give life birth, this discovery suggests that it’s possible. |© Society for Science & the Public 2000 - 2016
Moises Velasquez-Manoff This Valentine’s Day, as you bask in the beauty of your beloved, don’t just thank his or her genes and your good fortune; thank microbes. Research on the microbes that inhabit our bodies has progressed rapidly in recent years. Scientists think that these communities, most of which live in the gut, shape our health in myriad ways, affecting our vulnerability to allergic diseases like hay fever, how much weight we put on, our susceptibility to infection and maybe even our moods. They can also, it seems, make us sexy. Susan Erdman, a microbiologist at M.I.T., calls it the “glow of health.” The microbes you harbor, she argues, can make your skin smooth and your hair shiny; they may even put a spring in your step. She stumbled on the possibility some years ago when, after feeding mice a probiotic microbe originally isolated from human breast milk, a technician in her lab noticed that the animals grew unusually lustrous fur. Further observation of males revealed thick skin bristling with active follicles, elevated testosterone levels and oversize testicles, which the animals liked showing off. Microbes had transformed these animals into rodent heartthrobs. When given to females, the probiotic also prompted deeper changes. Levels of a protein called interleukin 10, which helps to prevent inflammatory disease and ensure successful pregnancy, went up, as did an important hormone called oxytocin. Oxytocin, often called the love hormone, helps mammals bond with one another. Our bodies may release it when we kiss (and mean it), when women breast-feed, even when people hang out with good friends. And the elevated oxytocin Dr. Erdman saw had important effects during motherhood. Some of the mice in her studies were eating a high-fat, high-sugar diet — junk-foody fare that’s known to shift the microbiome into an unhealthy state. Not surprisingly perhaps, mothers that didn’t imbibe the probiotics were less caring and tended to neglect their pups. But mothers that had high oxytocin thanks to the probiotic were nurturing and reared their pups more successfully. © 2017 The New York Times Company
Patti Neighmond It's tough to be a teenager. Hormones kick in, peer pressures escalate and academic expectations loom large. Kids become more aware of their environment in the teen years — down the block and online. The whole mix of changes can increase stress, anxiety and the risk of depression among all teens, research has long shown. But a recent study published in the journal Pediatrics suggests many more teenage girls in the U.S. may be experiencing major depressive episodes at this age than boys. And the numbers of teens affected took a particularly big jump after 2011, the scientists note, suggesting that the increasing dependence on social media by this age group may be exacerbating the problem. Psychiatrist Ramin Mojtabai and colleagues at Johns Hopkins University Bloomberg School of Public Health wanted to know whether rates of depression among teens had increased over the past decade. They analyzed federal data from interviews with more than 172,000 adolescents. Between 2005 and 2014, the scientists found, rates of depression went up significantly — if extrapolated to all U.S. teens it would work out to about a half million more depressed teens. What's more, three-fourths of those depressed teens in the study were girls. The findings are just the latest in a steady stream of research showing that women of all ages experience higher rates of depression compared to men, says psychologist and author Catherine Steiner-Adair. And no wonder, she says — despite gains in employment, education and salary, women and girls are still "continually bombarded by media messages, dominant culture, humor and even political figures about how they look — no matter how smart, gifted, or passionate they are." © 2017 npr
By STEPH YIN If you’re reading this at home, pause and put on a song you can’t resist dancing to. Go on, bop your head to the beat. Let yourself wiggle a bit. Throw in some arms and legs. If you’re reading this at work, maybe imagine these things at your desk. As you’re dancing, pay attention to where and how you’re moving. How much are you swaying your hips? Are your legs moving together or independently of each other? How vigorously are you moving your torso? You should note those movements, because very specific patterns may make some people appear to be better dancers than others. That’s the conclusion of a study published on Thursday in Scientific Reports, in which researchers asked 200 people to rate 39 female dancers. A few features stood out as contributing to higher-quality dance: big hip swings, and the right and left limbs moving independently of one another (which the researchers describe as asymmetric arm and thigh movements). The researchers speculate that those moves serve two purposes for heterosexual women. “One is, they’re showing off their reproductive quality, perhaps their hormonal status, to males,” said Nick Neave, an associate professor of psychology at Northumbria University in England and an author of the paper. “Another is, they’re showing off how good they are to female rivals.” In 2011, the same researchers reported that women preferred certain dance moves by men, especially exaggerated movements in the upper body. In other studies, Dr. Neave and his colleagues have found links between male dance attractiveness and risk-taking, as well as handgrip strength, a marker for overall body strength. “We know that dance moves are signaling strength and vigor in males,” Dr. Neave said. “Now we’re beginning to do the same research with females.” In the study, his team asked 39 female university students in Britain to dance alone to a drum beat. The researchers used a motion-capture system to track the women’s moves. They animated each dancer as an avatar to try to make sure that only the dance movements — and no other physical features — would affect ratings. Then they recruited 57 men and 143 women to watch 15-second clips of the avatars and rate them each on a numeric scale. © 2017 The New York Times Company
Having a thicker outer layer of the brain is linked to an increased likelihood of having autism. The cerebral cortex is the wrinkled outer layer of the brain that is responsible for many of our most human traits, including thought, language and consciousness. This layer is typically thicker in men than in women, and its structure has been linked to differences in personality. Now brain scans have shown that women who have a more male-like brain structure are three times more likely to have been diagnosed with autism. The study compared the brains of 98 men and women with high functioning autism with those of 98 people who don’t have autism. These findings provide new insights into the brain’s role in sex differences in autism, according to the team that did the study. Autism is thought to be two to five times more common in men than in women, and some think the condition is caused by having an “extreme male brain”. Journal reference: JAMA Psychiatry, DOI: 10.1001/jamapsychiatry.2016.3990 © Copyright Reed Business Information Ltd.
by Bethany Brookshire Gender bias works in subtle ways, even in the scientific process. The latest illustration of that: Scientists recommend women less often than men as reviewers for scientific papers, a new analysis shows. That seemingly minor oversight is yet another missed opportunity for women that might end up having an impact on hiring, promotions and more. Peer review is one of the bricks in the foundation supporting science. A researcher’s results don’t get published in a journal until they successfully pass through a gauntlet of scientific peers, who scrutinize the paper for faulty findings, gaps in logic or less-than-meticulous methods. The scientist submitting the paper gets to suggest names for those potential reviewers. Scientific journal editors may contact some of the recommended scientists, and then reach out to a few more. But peer review isn’t just about the paper (and scientist) being examined. Being the one doing the reviewing “has a number of really positive benefits,” says Brooks Hanson, an earth scientist and director of publications at the American Geophysical Union in Washington, D.C. “You read papers differently as a reviewer than you do as a reader or author. You look at issues differently. It’s a learning experience in how to write papers and how to present research.” Serving as a peer reviewer can also be a networking tool for scientific collaborations, as reviewers seek out authors whose work they admired. And of course, scientists put the journals they review for on their resumes when they apply for faculty positions, research grants and awards. |© Society for Science & the Public 2000 - 2017.
By Chelsea Whyte It was a gruesome scene. The body had severe wounds and was still bleeding despite having been lying for a few hours in the hot Senegalese savanna. The murder victim, a West African chimpanzee called Foudouko, had been beaten with rocks and sticks, stomped on and then cannibalised by his own community. This is one of just nine known cases where a group of chimpanzees has killed one of their own adult males, as opposed to killing a member of a neighbouring tribe. These intragroup killings are rare, but Michael Wilson at the University of Minnesota says they are a valuable insight into chimp behaviour such as male coalition building. “Why do these coalitions sometimes succeed, but not very often? It’s at the heart of this tension between conflict and cooperation, which is central to the lives of chimpanzees and even to our own,” he says. Chimps usually live in groups with more adult females than males, but in the group with the murder it was the other way round. “When you reverse that and have almost two males per every female — that really intensifies the competition for reproduction. That seems to be a key factor here,” says Wilson. Jill Pruetz at Iowa State University, who has been studying this group of chimpanzees in south-eastern Senegal since 2001, agrees. She suggests that human influence may have caused this skewed gender ratio that is likely to have been behind this attack. In Senegal, female chimpanzees are poached to provide infants for the pet trade. Fall from power Thirteen years ago, Foudouko reigned over one of the chimp clans at the Fongoli study site, part of the Fongoli Savanna Chimpanzee Project. As alpha male, he was “somewhat of a tyrant”, Pruetz says. © Copyright Reed Business Information Ltd.
Nicola Davis Girls as young as six years old believe that brilliance is a male trait, according research into gender stereotypes. The US-based study also found that, unlike boys, girls do not believe that achieving good grades in school is related to innate abilities. Andrei Cimpian, a co-author of the research from New York University, said that the work highlights how even young children can absorb and be influenced by gender stereotypes – such as the idea that brilliance or giftedness is more common in men. Are gendered toys harming childhood development? Read more “Because these ideas are present at such an early age, they have so much time to affect the educational trajectories of boys and girls,” he said. Writing in the journal Science, researchers from three US universities describe how they carried out a range of tests with 400 children, half of whom were girls, to probe the influence of gender stereotypes on children’s notions of intelligence and ability. In the first test, a group of 96 boys and girls of ages five, six and seven, were read a story about a highly intelligent person, and were asked to guess the person’s gender. They were then presented with a series of pictures showing pairs of adults, some same-sex, some opposite sex, and were asked to pick which they thought was highly intelligent. Finally, the children were asked to match certain objects and traits, such as “being smart”, to pictures of men and women. © 2017 Guardian News and Media Limited
By NATALIE ANGIER Whether personally or professionally, Daniel Kronauer of Rockefeller University is the sort of biologist who leaves no stone unturned. Passionate about ants and other insects since kindergarten, Dr. Kronauer says he still loves flipping over rocks “just to see what’s crawling around underneath.” In an amply windowed fourth-floor laboratory on the east side of Manhattan, he and his colleagues are assaying the biology, brain, genetics and behavior of a single species of ant in ambitious, uncompromising detail. The researchers have painstakingly hand-decorated thousands of clonal raider ants, Cerapachys biroi, with bright dots of pink, blue, red and lime-green paint, a color-coded system that allows computers to track the ants’ movements 24 hours a day — and makes them look like walking jelly beans. The scientists have manipulated the DNA of these ants, creating what Dr. Kronauer says are the world’s first transgenic ants. Among the surprising results is a line of Greta Garbo types that defy the standard ant preference for hypersociality and instead just want to be left alone. The researchers also have identified the molecular and neural cues that spur ants to act like nurses and feed the young, or to act like queens and breed more young, or to serve as brutal police officers, capturing upstart nestmates, spread-eagling them on the ground and reducing them to so many chitinous splinters. Dr. Kronauer, who was born and raised in Germany and just turned 40, is tall, sandy-haired, blue-eyed and married to a dentist. He is amiable and direct, and his lab’s ambitions are both lofty and pragmatic. “Our ultimate goal is to have a fundamental understanding of how a complex biological system works,” Dr. Kronauer said. “I use ants as a model to do this.” As he sees it, ants in a colony are like cells in a multicellular organism, or like neurons in the brain: their fates joined, their labor synchronized, the whole an emergent force to be reckoned with. © 2017 The New York Times Company
written by Claire Lehmann I learned about Debra through reading her LA Times op-ed on the futility of gender neutral parenting. I got in touch with Debra because I wanted to learn more about her field of sex neuroscience, her own research and her thoughts on studying sex differences in the brain. Because the study of sex and sex differences is often fraught with political roadblocks, I also wanted to get a picture of how a neuroscientist-sex researcher approaches some of these contentious issues. Hi Debra, thanks for chatting to Quillette. Can you briefly tell us who you are — where you studied, who was your supervisor and what made you interested in neuroscience, in particular sex neuroscience? I am a sex researcher at York University in Toronto and I write about the science of sex for several media outlets, including Playboy. For my PhD, which I just defended, I worked with Dr. Keith Schneider, who has pioneered new methods in high-resolution fMRI and is the Director of the University of Delaware’s Center for Biomedical and Brain Imaging, and Dr. James Cantor at the University of Toronto, who is a world expert in the brain imaging of pedophilia. I remember opening up a textbook during my first neuroscience course as an undergraduate student, seeing images from an fMRI study, and thinking it was incredible. I decided to pursue neuroscience in grad school and had the opportunity to do a placement in sexology as part of my Master’s degree. That’s how I got hooked! And I haven’t looked back. © 2017 Quillette
In the mood? Feeling sexy and romantic has been linked to a hormone named kisspeptin. Researchers hope the chemical may help treat people with some sexual problems. Kisspeptin occurs naturally in the body, where it stimulates the release of other signalling chemicals that have been linked to reproduction. Now a study of 29 heterosexual young men has found that injections of the hormone enhance the brain’s response to sexual and romantic pictures of couples. After injection, MRI scans showed increased activity in the regions of the brain that are usually stimulated by sexual arousal and romance. But this activity was only prompted by arousing pictures – non-sexy images did not have the same effect. “Our findings indicate that kisspeptin could play a role in stimulating some of the emotions and responses that lead to sex and reproduction,” says Waljit Dhillo, at Imperial College London. “Ultimately, we are keen to look into whether kisspeptin could be an effective treatment for psychosexual disorders.” The team now plans to study the effects of the hormone in a larger group of people, including women as well as men. Journal reference: Journal of Clinical Investigation © Copyright Reed Business Information Ltd.
By NANCY L. SEGAL and SATOSHI KANAZAWA In 1973, the biologist Robert Trivers and the computer scientist Dan Willard made a striking prediction about parents and their offspring. According to the principles of evolutionary theory, they argued, the male-to-female ratio of offspring should not be 50-50 (as chance would dictate), but rather should vary as a function of how good (or bad) the conditions are in which the parents find themselves. Are the parents’ resources plentiful — or scarce? The Trivers-Willard hypothesis holds that when their conditions are good, parents will have more male offspring: Males with more resources are likely to gain access to more females, thereby increasing the frequency with which their genes (and thus their parents’ genes) are preserved in future generations. Conversely, male offspring that lack resources are likely to lose out to males that have more resources, so in bad conditions it pays for parents to “invest” more in daughters, which will have more opportunities to mate. It follows, as a kind of corollary, that when parents have plentiful resources they will devote those resources more to their sons, whereas when resources are scarce, parents will devote them more to their daughters. In short: If things are good, you have more boys, and give them more stuff. If things are bad, you have more girls, and give more of your stuff to them. Is this hypothesis correct? In new research of ours, to be published in the April issue of The Journal of Experimental Child Psychology, we suggest that in the case of breast-feeding, at least, it appears to be. In recent years, evidence has emerged suggesting that in various mammalian species, breast milk — which is, of course, a resource that can be given to children — is tailored for the sex of each offspring. For example, macaque monkey mothers produce richer milk (with higher gross energy and fat content) for sons than for daughters, but also provide greater quantities of milk and higher concentrations of calcium for daughters than for sons. © 2017 The New York Times Company
By Kevin Pelphrey, In September, the Florida State University football team made a visit to a Tallahassee middle school that would become famous. At lunchtime, student-athlete Travis Rudolph noticed sixth grader Bo Paske eating alone, so he joined Bo for the meal. Bo, who has autism, often sat by himself in the lunchroom. The world took note of the athlete’s gesture after his mother’s Facebook post about it went viral. “This is one day I didn’t have to worry if my sweet boy ate lunch alone, because he sat across from someone who is a hero in many eyes,” she wrote. This story touched people because it calls to mind something universal: the sting of social exclusion. We have all known children who often eat, or play, alone. And all of us have felt left out at one time or another. But although this experience may be universal, a new generation of children is experiencing a wave of inclusiveness. Technology of various types, often thought of as an isolating influence, can actually abet people’s good intentions or help those with autism learn to fit in. One new app called Sit With Us, invented by 16-year-old Natalie Hampton, helps vulnerable children who have difficulty finding a welcoming group in the lunchroom. Its motto is inspiring: “The first step to a warmer, more inclusive community can begin with LUNCH.” Sit With Us allows students to designate themselves as ‘ambassadors’ and to signal to anyone seeking company that they’re invited to join the ambassador’s table. © 2017 Scientific American
By Alice Klein Who needs men? A female shark separated from her long-term mate has developed the ability to have babies on her own. Leonie the zebra shark (Stegostoma fasciatum) met her male partner at an aquarium in Townsville, Australia, in 1999. They had more than two dozen offspring together before he was moved to another tank in 2012. From then on, Leonie did not have any male contact. But in early 2016, she had three baby sharks. Intrigued, Christine Dudgeon at the University of Queensland in Brisbane, Australia, and her colleagues began fishing for answers. Zoologger: The amphibious fish that mates with itself One possibility was that Leonie had been storing sperm from her ex and using it to fertilise her eggs. But genetic testing showed that the babies only carried DNA from their mum, indicating they had been conceived via asexual reproduction. Some vertebrate species have the ability to reproduce asexually even though they normally reproduce sexually. These include certain sharks, turkeys, Komodo dragons, snakes and rays. However, most reports have been in females who have never had male partners. There are very few reports of asexual reproduction occurring in females with previous sexual histories, says Dudgeon. An eagle ray and a boa constrictor, both in captivity, are the only other female animals that have been documented switching from sexual to asexual reproduction. © Copyright Reed Business Information Ltd.
Keyword: Sexual Behavior
Link ID: 23110 - Posted: 01.17.2017
By LISA SANDERS, M.D. “You don’t look well,” the man at the gas station told the older woman in the car. He’d known her for years, always thinking of her as a lively, robust woman. But that day she looked pale and tired. Her sharp blue eyes seemed dim. She gave a feeble smile. “I don’t feel well at all,” she told him. There’s an urgent-care clinic just up the street, he said. Could she make it there? She was nearly 45 minutes away from her home in Halifax, Nova Scotia. Stopping just up the street seemed a much better option. At the clinic, the doctor took one look at her, put a blood pressure cuff around her arm and told her assistant to call an ambulance. The rest of the day was a blur. The woman remembers being bundled onto a stretcher and one of the E.M.T.s saying her blood pressure was very low. It was an odd thing to hear, because her blood pressure was usually high enough to require three medications. She was taken to the emergency room at the Queen Elizabeth II Health Sciences Center in Halifax. She remembers being fussed over — having blood drawn, receiving intravenous fluids, feeling sticky snaps being placed on her chest that connected her to a continuous heart monitor. She had been a nurse for many years when she was younger, yet seeing herself at the center of these familiar activities was strange. A blood test indicated that there may have been damage to her heart. The doctor told her she was having a heart attack, she recalls. You’ve got the wrong patient, she thought to herself. Sure, she had a little high blood pressure, a little asthma, a little back pain. But problems with her heart? Never. The patient used a cane, but she had no difficulty getting up on the exam table — an important test of mobility. © 2017 The New York Times Company
Keyword: Hormones & Behavior
Link ID: 23101 - Posted: 01.14.2017
By Virginia Morell Only three known species go through menopause: killer whales, short-finned pilot whales, and humans. Two years ago, scientists suggested whales do this to focus their attention on the survival of their families rather than on birthing more offspring. But now this same team reports there’s another—and darker—reason: Older females enter menopause because their eldest daughters begin having calves, leading to fights over resources. The findings might also apply to humans, the scientists say. “What an interesting paper,” says Phyllis Lee, a behavioral ecologist at the University of Stirling in the United Kingdom, who was not involved in the study. “It brings two perspectives on menopause neatly together, and provides an elegant model for its rarity.” The new work came about when Darren Croft, a behavioral ecologist at the University of Exeter in the United Kingdom, and his colleagues looked back on their 2015 killer whale menopause study. “That showed how they helped and why they lived so long after menopause, but it didn’t explain why they stop reproducing,” he says, noting that in other species, such as elephants, older females also share wisdom and knowledge with their daughters, but continue to have calves. © 2017 American Association for the Advancement of Science.
By Andy Coghlan Can tiny brains grown in a dish reveal the secrets of sociability? Balls of brain tissue generated from stem cells are enabling us to understand the underlying differences between people who struggle to be sociable and those who have difficulty reining themselves in. Alysson Muotri at the University of California, San Diego, and his team created the mini-brains by exposing stem cells taken from the pulp of children’s milk teeth to cocktails of growth factors that help them mature. Eventually, they can develop as many as six layers of cerebral cortex – the outer surface of the brain. This region is much more sophisticated in humans than in other animals, and houses important circuitry governing our most complex thoughts and behaviours, including socialising with others. Each mini-brain is approximately 5 millimetres across. “Though they’re not as well defined as they are in a real brain, they resemble what you find in an embryonic fetus,” says Muotri. To understand how brain development affects sociability, the team used donated cells from children with autism and Rett syndrome, both of which are associated with impaired communication skills. They also used cells from children with Williams syndrome, a condition characterised by a hyper-sociable nature. People with Williams syndrome can be unable to restrain themselves from talking to complete strangers. © Copyright Reed Business Information Ltd.
By Alice Klein Mothers hold their children more on the left and wild mammals seem to keep their young more on that so too, at least when fleeing predators. Now it seems many mammal babies prefer to approach their mother from one side too – and the explanation may lie in the contrasting talents of each half of the brain. In mammals, the brain’s right hemisphere is responsible for processing social cues and building relationships. It is also the half of the brain that receives signals from the left eye. Some researchers think this explains why human and ape mothers tend to cradle their babies on the left: it is so they can better monitor their facial expressions with their left eye. Now, Janeane Ingram at the University of Tasmania, Australia, and her colleagues have looked at whether animal infants also prefer to observe their mum from one side. The team studied 11 wild mammals from around the world: horses, reindeer, antelopes, oxen, sheep, walruses, three species of whale and two species of kangaroo. Whenever an infant approached its mother from behind, the researchers noted whether it positioned itself on its mum’s left or right side. They recorded almost 11,000 position choices for 175 infant-mother pairs. Infants of all species were more likely to position themselves so that their mother was on their left. This happened about three-quarters of the time. © Copyright Reed Business Information Ltd.
By Virginia Morell Japanese macaques and sika deer live comfortably together on Japan’s Yakushima Island: The deer eat fruit the monkeys drop from the trees, and the monkeys groom and sometimes hitch a ride on the deer. But a couple years ago, one of the macaques took this relationship to a new level. Unable to get a mate of his own kind, this low-ranking snow monkey used the deer’s back for his pleasure (as pictured, and also shown in this not-suitable-for-work video). He did not penetrate her, but did ejaculate, and the deer then licked her back clean, researchers report in the current issue of Primates. The monkey was later seen attempting to mount another deer, but she objected and threatened him. He also guarded his unlikely love interests, chasing away any other male monkeys who came near. Scientists have only reported one other case of sexual relations in the wild between unrelated species. That one involved male Antarctic fur seals coercing king penguins; once, after sating his lust, the seal ate the bird. In both cases, scientists suspect that the males were unable to acquire a mate of their own kind, and seasonal hormonal surges led them to seek love elsewhere. © 2017 American Association for the Advancement of Science.
Keyword: Sexual Behavior
Link ID: 23074 - Posted: 01.10.2017