By Hannah Thomasy Some 2 percent of men in the U.S. identify as bisexual. But, for decades, some sexuality researchers have questioned whether true bisexual orientation exists in men. In 2005, J. Michael Bailey, a sexuality researcher at Northwestern University, and two colleagues showed men who identify as bisexual brief pornographic clips featuring men or women, while measuring their subjects’ self-reported arousal and change in penis circumference. The results, when compared to men who identified as straight or gay, led them to conclude that the men identifying as bisexual did not actually have “strong genital arousal to both male and female sexual stimuli.” This was in contrast to work on sexual arousal in women, which showed that they — whether identifying as straight or gay — were physically aroused by both male and female stimuli. A New York Times headline covering Bailey’s 2005 study on men declared: “Straight, Gay, or Lying? Bisexuality Revisited.” But the paper also spurred more research into the subject — some of which has now led Bailey to revise his conclusions. In a paper published last month in the Proceedings of the National Academy of Sciences (PNAS), Bailey and 12 colleagues reanalyzed data from eight previously published studies of bisexual-identified men, including the 2005 paper. The new review finds that men who reported attraction to both men and women do in fact show genital arousal towards both male and female stimuli. The data, the authors conclude, offers “robust evidence for bisexual orientation among men.” The PNAS study has drawn positive coverage and received praise from some activists, who see it as valuable confirmation for an often-marginalized sexual identity. But it has also received backlash from other scientists and many bisexual people, some of whom argue that in attempting to prove, based on genital arousal, that bisexuality exists, researchers are discounting bisexual people’s lived experiences. It has also reignited a broader debate over the ethics of human sexuality research — and about what role, if any, scientists should play in validating the experiences of queer people.

Keyword: Sexual Behavior
Link ID: 27422 - Posted: 08.18.2020

By Joshua Sokol A beast calls in the distance. Hearing a low rumble, you might imagine the source will be an unholy cross between a wild boar and a chain saw. The message is unmistakable: I’m here, I’m huge and you can either come mate with me or stay out of my way. Surprise! It’s just a cuddly little koala. Like online dating, the soundscape of the animal world is rife with exaggerations about size, which animals use to scare off rivals and attract mates. Gazelles, howler monkeys, bats and many more creatures have evolved to create calls with deep sonic frequencies that sound as if they come from a much larger animal. Now scientists have proposed this same underlying pressure to exaggerate size might be linked to an even deeper mystery. It could have spurred mammals toward developing the ability to make a wider array of possible calls, to mimic sounds after hearing them and maybe even speech, what scientists call vocal learning. “We are offering one possible way for vocal learning to have evolved,” says Maxime Garcia, a biologist at the University of Zurich in Switzerland who suggested the relationship with his colleague, Andrea Ravignani, in the journal Biology Letters this month. Their idea builds off previous studies on vocal learning in humans. Beyond just opera singers, beatboxers and Michael Winslow from the “Police Academy” movies, we all have some level of control over the frequencies of our voices. “I can tell you to lower your pitch or try to sound big, and you can soound like thissss,” said Katarzyna Pisanski at the University of Lyon in France, affecting a deep voice. © 2020 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 27393 - Posted: 07.31.2020

Ian Sample Science editor Scientists have unravelled the mysterious mechanism behind the armpit’s ability to produce the pungent smell of body odour. Researchers at the University of York traced the source of underarm odour to a particular enzyme in a certain microbe that lives in the human armpit. To prove the enzyme was the chemical culprit, the scientists transferred it to an innocent member of the underarm microbe community and noted – to their delight – that it too began to emanate bad smells. The work paves the way for more effective deodorants and antiperspirants, the scientists believe, and suggests that humans may have inherited the mephitic microbes from our ancient primate ancestors. “We’ve discovered how the odour is produced,” said Prof Gavin Thomas, a senior microbiologist on the team. “What we really want to understand now is why.” Humans do not produce the most pungent constituents of BO directly. The offending odours, known as thioalcohols, are released as a byproduct when microbes feast on other compounds they encounter on the skin. The York team previously discovered that most microbes on the skin cannot make thioalcohols. But further tests revealed that one armpit-dwelling species, Staphylococcus hominis, was a major contributor. The bacteria produce the fetid fumes when they consume an odourless compound called Cys-Gly-3M3SH, which is released by sweat glands in the armpit. Advertisement Humans come with two types of sweat glands. Eccrine glands cover the body and open directly onto the skin. They are an essential component of the body’s cooling system. Apocrine glands, on the other hand, open into hair follicles, and are crammed into particular places: the armpits, nipples and genitals. Their role is not so clear. © 2020 Guardian News & Media Limited

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 27390 - Posted: 07.29.2020

A scientific analysis of more than 2,000 brain scans found evidence for highly reproducible sex differences in the volume of certain regions in the human brain. This pattern of sex-based differences in brain volume corresponds with patterns of sex-chromosome gene expression observed in postmortem samples from the brain’s cortex, suggesting that sex chromosomes may play a role in the development or maintenance of sex differences in brain anatomy. The study, led by researchers at the National Institute of Mental Health (NIMH), part of the National Institutes of Health, is published in Proceedings of the National Academy of Sciences. “Developing a clearer understanding of sex differences in human brain organization has great importance for how we think about well-established sex differences in cognition, behavior, and risk for psychiatric illness. We were inspired by new findings on sex differences in animal models and wanted to try to close the gap between these animal data and our models of sex differences in the human brain,” said Armin Raznahan, M.D., Ph.D., study co-author and chief of the NIMH Section on Developmental Neurogenomics. Researchers have long observed consistent sex-based differences in subcortical brain structures in mice. Some studies have suggested these anatomical differences are largely due to the effects of sex hormones, lending weight to a “gonad-centric” explanation for sex-based differences in brain development. However, more recent mouse studies have revealed consistent sex differences in cortical structures, as well, and gene-expression data suggest that sex chromosomes may play a role in shaping these anatomical sex differences. Although the mouse brain shares many similarities with the human brain, it is not clear whether these key findings in mice also apply to humans.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 27377 - Posted: 07.21.2020

Ruairi J MacKenzie Research into developing treatments for psychiatric illness is missing out vital data from female animals, producing drugs that aren’t optimized for women and contributing to the failure of clinical trials, said a panel of neuroscientists today at FENS Virtual Forum of Neuroscience. In a press conference, Professor Christina Dalla from the National and Kapodistrian University of Athens, Dr Debra Bangasser from Temple University and Professor Mohammed Milad at New York University Grossman School of Medicine spoke of the impacts of the inequitable use of female animals on their research areas. Dalla reviewed the targeting of the hypothalamic–pituitary–adrenal (HPA) axis using antidepressants. The HPA axis is a major neuroendocrine system that regulates responses to stress and many other bodily processes. Dysfunctions in the HPA axis have long thought to be a factor in the onset of depression, but drugs targeting this axis have roundly failed in clinical trials. Dalla proposed that this failure may partly be the result of pre-clinical studies using male animals, followed by clinical trials that often recruit more women than men. Bangasser and Milad respectively showed how responses to stress and fear also vary between male and female mice. The Forum, held online for the first time, has extensively addressed the representation of women in the field in its program, opening with a Mini-Conference led by the Cajal Club that celebrated the impact of women in the development of neuroscience.

Keyword: Sexual Behavior
Link ID: 27376 - Posted: 07.21.2020

by Chloe Williams A new wireless device activates a mouse’s neurons as it navigates a cage with food, hiding places and other mice, allowing researchers to study social behavior in a realistic environment1. Experiments using this setup suggest that oxytocin has distinct effects in different contexts — which may be particularly important as researchers explore the hormone’s value as a potential treatment for autism. The device makes use of optogenetics, a technique in which researchers use pulses of light to activate or silence neurons. Autism researchers have used the approach to manipulate neural circuits in mice, but traditional optogenetic devices involve a fiber-optic cable, which tethers the animal and interferes with social interactions. Other wireless devices have been able to activate neurons without a tether, but researchers have mostly used them to study social behavior involving just two mice interacting for only about 15 minutes in an otherwise empty cage — a scenario that fails to capture a full range of mouse behaviors2. The new wireless device, powered by two watch batteries, consists of a light-emitting diode attached to an optical fiber that is implanted into the brain. It has an on-off switch that allows researchers to control it remotely using a magnet placed inside the cage. Using this setup, researchers can modulate brain activity in a group of mice as they roam for days through a cage that has hiding places, platforms, a nest, food and water. The device’s designers tested it in mice engineered to express light-sensitive proteins in part of the hypothalamus. This region produces the hormone oxytocin, generally thought to reduce aggression and enhance social bonds. When delivered as a nasal spray, it improves social skills in some people with autism. © 2020 Simons Foundation

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 27369 - Posted: 07.16.2020

As we open computers to connect with each other remotely, motor neurons in our spinal cord are opening synaptic pathways to connect with our muscles physically. We rarely think about these electrical signals passing back and forth between computers or our neurons and muscles, until those signals are lost. Kennedy’s disease, a neuromuscular degenerative disease, affects 1 in 40,000 men every year. Little progress has been made in understanding its biological basis since it was identified in the 1960s, but one promising lead may be a family of proteins known as neurotrophic factors. MSU scientists Cynthia Jordan, professor in the College of Natural Science Neuroscience Program, and Katherine Halievski, former Ph.D. student in Jordan’s Lab and lead author, published a benchmark study in the Journal of Physiology describing the key role of one of these proteins in Kennedy’s disease: Brain-Derived Neurotrophic Factor (BDNF). “There were stories that neurotrophic factors could slow down neurodegenerative diseases, but where they fell short was really understanding how they slow down the disease,” Jordan explained. “Where this paper and Katherine’s work stand alone is in using classic neuroscience techniques to understand how BDNF improved neuromuscular function at the cellular level.” Motor neurons are cells that carry signals from the brain to every muscle in the body — fast twitch muscles that perform quick, high impact movements such as jumping, and slow-twitch muscles that sustain long contractions such as standing. At each step in the pathway — from the neuron, along the synaptic pathway and to the muscle — BDNF supports the process, giving both neurons and muscles what they need to connect, survive and thrive. © Michigan State University

Keyword: Movement Disorders; Hormones & Behavior
Link ID: 27320 - Posted: 06.24.2020

By Elizabeth Preston A clown fish uses his fins to fan water across a glistening mass of eggs, keeping them aerated. A silver arowana scoops up his fertilized eggs with his mouth and holds them gently for two months, until a host of miniature adults swims free from his jaws. A seahorse drifts through coral, his belly pouch swollen with unborn young. Most fish are uninvolved parents. They dump their eggs and sperm, then swim off and let nature take its course. But some species of fish take their parental duties more seriously — and among them, the majority of caring parents are dads. Care from mothers, or from both parents at once, is much less common. In a study published last fall in Evolution, researchers found evidence that paternal care, the system in which dads are the sole caretakers, has evolved dozens of times in fish. These fish aren’t exactly helicopter dads. Their most common parenting style is simply guarding eggs after they’re fertilized. “Some people are surprised this is considered care,” said Frieda Benun Sutton, an evolutionary biologist at the City University of New York. But it does count. To learn more about why this type of care in fish usually comes from dads, Dr. Benun Sutton and her co-author, Anthony Wilson, of Brooklyn College, took a deep dive into the family history of fish parents. They started with an evolutionary tree, built by other researchers in 2017 using genetic data, that shows how almost 2,000 fish species are related. Then they mapped onto the tree all the information they could find about parental care in those species: Were young cared for by fathers, mothers, both or nobody? They also added other factors including the size and number of each fish’s eggs and how they’re fertilized. The completed tree showed that care by fathers is no evolutionary accident: It has arisen at least 30 separate times. Hundreds of the species in this sample have absent mothers and caring fathers. But why? © 2020 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 27316 - Posted: 06.22.2020

By Bethany Brookshire Biomedical science has historically been a male-dominated world — not just for the scientists, but also for their research subjects. Even most lab mice were male (SN: 6/18/19). But now, a new study shows that researchers are starting to include more females — from mice to humans — in their work. In 2019, 49 percent of articles surveyed in biomedical science used both male and female subjects, almost twice as many as a decade before, according to findings published June 9 in eLife. A study of articles published in 2009 across 10 biomedical disciplines showed a dismal picture. Only 28 percent of 841 research studies included both males and female subjects. The results were published in 2011 in Neuroscience and Biobehavioral Reviews. The scientific world took note. In 2016, the U.S. National Institutes of Health instituted the Sex as a Biological Variable policy in an effort to correct the imbalance. Scientists had to use both males and females in NIH-funded research unless they could present a “strong justification” otherwise. Annaliese Beery, a neuroscientist at Smith College in Northhampton, Mass., conducted the original study showing the extent of sex bias in research. In 2019, she and Nicole Woitowich, a chemist at Northwestern University in Evanston, Ill., wanted to see if sex bias was still as strong as it was in 2009. Have things improved? After scanning another 720 articles across nine of the 10 original disciplines, the researchers have shown that yes, they have, with nearly half of all journal articles including both males and females. Behavioral research was the most inclusive, with both sexes in 81 percent of studies. Overall, six out of nine fields surveyed showed a significant increase in studies that included both sexes. © Society for Science & the Public 2000–2020

Keyword: Sexual Behavior
Link ID: 27297 - Posted: 06.10.2020

By Yasmin Anwar, Media Relations Stephen Glickman, a pioneer in behavioral endocrinology and founder of the world’s first colony of captive spotted hyenas — he raised generations of them in a UC Berkeley research facility — died at his home in Berkeley on May 22 from pancreatic cancer. He was 87. A professor emeritus of psychology and of integrative biology, whose lifelong bond with animals began during his boyhood near the Bronx Zoo in New York, Glickman joined the UC Berkeley faculty in 1968. Over the next five decades, he conducted studies of creatures great and small, authoring more than 100 research papers. His sharp intellect, warm wit and overall lovability engaged peers and protégés in scientific and social justice pursuits, colleagues said. “Steve was a giant in the field of animal behavior,” said UC Berkeley psychology chair Ann Kring. “He studied a wide variety of species in the wild, at the zoo and, perhaps most famously, at the field station where he conducted work with hyenas for more than 30 years.” Glickman’s standout legacy is his ardent stewardship of a colony of spotted hyenas at UC Berkeley’s Field Station for the Study of Behavior, Ecology and Reproduction. The hyena compound in the Berkeley hills, above the campus, closed in 2014 when funding dried up, but not before yielding seminal discoveries about endocrinology, fertility and other medical conditions that affect humans. Hormone-driven matriarchy By studying female hyenas, who use a long, phallic clitoris, instead of a vagina, for mating and giving birth, Glickman and fellow researchers found that high levels of androgens produced in their ovaries masculinized their sex organs and boosted their aggression and dominance in the pack. Copyright © 2020 UC Regents; all rights reserved

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 27292 - Posted: 06.09.2020

By Meredith Wadman In January, one of the first publications on those sickened by the novel coronavirus in Wuhan, China, reported that three out of every four hospitalized patients were male. Data from around the world have since confirmed that men face a greater risk of severe illness and death from COVID-19 than women and that children are largely spared. Now, scientists investigating how the virus does its deadly work have zeroed in on a possible reason: Androgens—male hormones such as testosterone—appear to boost the virus’ ability to get inside cells. A constellation of emerging data supports this idea, including COVID-19 outcomes in men with prostate cancer and lab studies of how androgens regulate key genes. And preliminary observations from Spain suggest that a disproportionate number of men with male pattern baldness—which is linked to a powerful androgen—end up in hospitals with COVID-19. Researchers are rushing to test already approved drugs that block androgens’ effects, deploying them early in infection in hopes of slowing the virus and buying time for the immune system to beat it back. “Everybody is chasing a link between androgens … and the outcome of COVID-19,” says Howard Soule, executive vice president at the Prostate Cancer Foundation, who on 13 May ran a Zoom call presenting the newest research that drew 600 scientists and physicians. A second call scheduled for today will discuss incipient clinical trials. Epidemiological data from around the world have confirmed the early reports of male vulnerability. In Lombardy in Italy, for example, men comprised 82% of 1591 patients admitted to intensive care units (ICUs) from 20 February to 18 March, according to a JAMA paper. And male mortality exceeded that of women in every adult age group in another JAMA study of 5700 New York City patients hospitalized with COVID-19. © 2020 American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 27284 - Posted: 06.04.2020

By Nicholas Bakalar Women who take benzodiazepines, such as Valium or Xanax, before becoming pregnant may be at increased risk for ectopic pregnancy, a new study found. An ectopic, or tubal, pregnancy is one in which a fertilized egg grows outside the uterus, often in a fallopian tube, and it is a life-threatening event. The egg must be removed with medication or surgery. Benzodiazepines, sold by prescription under several brand names, are widely prescribed for anxiety, sleep problems and seizures. The study, in Human Reproduction, used an insurance database of 1,691,366 pregnancies to track prescriptions for benzodiazepines in the 90 days before conception. Almost 18,000 of the of the women had used the drugs, and the scientists calculated that these women were 47 percent more likely to have a tubal pregnancy than those who did not. The study controlled for other risks for tubal pregnancy, including sexually transmitted infections, pelvic infection, use of an intrauterine device, smoking and fertility treatments. “Women planning a pregnancy who are using these drugs should talk to their care provider to see whether a change in treatment is possible, and then slowly change treatment before going off their contraceptive,” said the lead author, Elizabeth Wall-Wieler, a postdoctoral fellow at Stanford University. “Women for whom there is no alternative, or who have an unplanned pregnancy, should let their care provider know, and those pregnancies should be monitored carefully. The key to treating ectopic pregnancy is to treat it early.” © 2020 The New York Times Company

Keyword: Drug Abuse; Sexual Behavior
Link ID: 27278 - Posted: 06.04.2020

by Marcus A. Banks Brain structures differ in volume depending on a person’s social environment and socioeconomic status, and between men and women, according to a new analysis1. The findings could help explain differences seen in the brains of autistic women and men, many of whom find social communication challenging. Researchers analyzed brain scans from about 10,000 people enrolled in the UK Biobank, a large-scale initiative to understand health trends in the United Kingdom. The participants were 55 years old, on average. They completed surveys, answering questions about their income level, satisfaction with friends and family, participation in social activities and feelings of loneliness. The researchers found that associations between the survey responses and the volume of brain regions linked to social contact differ by sex. For example, women who live with two or more people have a larger amygdala — a brain region involved in decision-making and emotional responses — than do women from smaller households. By contrast, household size has little effect on the size variation of amygdalae among men. The study appeared 18 March in Science Advances. The scans also showed that men who say they lack social support from siblings and friends tend to have a larger nucleus accumbens, part of the brain’s reward circuitry, than men who reported having more social support. The researchers did not see this difference in women. Other differences between men and women appeared in networks involving multiple brain regions, such as those involved with visual processing. © 2020 Simons Foundation

Keyword: Sexual Behavior; Brain imaging
Link ID: 27260 - Posted: 05.21.2020

Dana Najjar The old riddle, “Which came first, the chicken or the egg?” is relatively easy to answer as a question about the evolution of birth in animals. Egg laying almost certainly came before live birth; the armored fish that inhabited the oceans half a billion years ago and were ancestral to all land vertebrates seem to have laid eggs. But the rest of the story is far from straightforward. Over millennia of evolution, nature has come up with only two ways for a newborn animal to come into the world. Either its mother lays it in an egg, where it can continue to grow before hatching, or it stays inside its mother until emerging as a more fully formed squirming newborn. “We have this really fundamental split,” said Camilla Whittington, a biologist at the University of Sydney. Is there some primordial reason for this strict reproductive dichotomy between egg laying (oviparity) and live birth (viviparity)? When and why did live birth evolve? These are just some of the questions that new research — including studies of a remarkable lizard that can lay eggs and bear live young at the same time — is exploring, all the while underscoring the enormous complexity and variability of sexual reproduction. Early female animals laid eggs in the sense that they released their ova into the world, often thousands at a time. Sperm released by males then fertilized some of these eggs in a hit-or-miss fashion, and the resulting embryos took their chances on surviving in the hostile world until they hatched. Many creatures, particularly small, simple ones, still reproduce this way. All Rights Reserved © 2020

Keyword: Sexual Behavior; Evolution
Link ID: 27257 - Posted: 05.20.2020

By Katherine Ellison After a lifetime of arriving late, missing deadlines and having friends call her a ditz, Leslie Crawford wanted to know whether her chronic distraction meant she had attention-deficit/hyperactivity disorder, ADHD. And, if that were true, could medication help? Over three visits with her managed-care plan doctor in San Francisco, Crawford, 57, a busy mother of two and professional editor, complied with urine and blood tests some doctors require to rule out drug abuse, and was checked for any preexisting heart condition that might make stimulants too risky. Then came the last step: a telephone interview. “What kind of student were you in elementary school?” she remembers the psychiatrist asking. “I was an A student,” Crawford answered. “I’m sorry,” he said, as Crawford recalled. “You don’t meet the qualification for ADHD and we can’t give you medication.” AD “I couldn’t believe it,” Crawford said later. Two private therapists had already told her she had ADHD, she said. But her plan’s psychiatrist said it was company policy to deny diagnosis and medication if a patient had done well in school as a child. This left Crawford with the option of paying several hundred dollars for a private psychiatrist’s evaluation, plus recurring costs for new prescriptions over time. For now, she’s not pursuing that. After her three appointments, “I just felt exhausted,” she said. ADHD affects more than 16 million U.S. children and adults. Despite decades of research involving thousands of studies, it remains one of the most perplexing of mental health diagnoses, susceptible to confusion and controversy even among doctors who treat it. The muddle can be particularly damaging to girls and women, who like Crawford may miss early treatment that could have spared them years of shame, anxiety, depression, self-harm and even suicide attempts.

Keyword: ADHD; Sexual Behavior
Link ID: 27252 - Posted: 05.18.2020

By Kim Severson In the 1980s, when marriage and adopting children seemed impossible dreams for gay men, the psychoanalyst Richard C. Friedman became their champion. His 1988 book, “Male Homosexuality: A Contemporary Psychoanalytic Perspective,” showed that sexual orientation was largely biological and presented a case that helped undermine the belief held by most Freudian analysts at the time that homosexuality was a pathology that could somehow be cured. “I felt an ethical obligation to find the reasons for anti-homosexual prejudice,” he once told an interviewer. His wife, Susan Matorin, a clinical social worker at the Weill Medical College of Cornell, put it more plainly: “Straight people had the same personality issues, and they got away with murder, but gay people were stigmatized, and he didn’t think that was right.” Dr. Friedman’s motivation wasn’t political. “He very much felt like you followed the science, and it didn’t matter what the political backdrop was,” his son, Jeremiah, a screenwriter in Los Angeles, said in a phone interview. Although the American Psychiatric Association, the dominant mental health organization in the United States, changed its diagnostic manual in 1973 and stopped classifying homosexuality as an illness, psychoanalysts continued to describe homosexuality as a perversion, and many believed it could be cured. Dr. Friedman, using studies of identical twins and theories of developmental psychology, made a scholarly rather than ideological case that biology rather than upbringing played a significant role in sexual orientation. It was a direct challenge to popular Freudian theories and thrust him into the center of debates among the more established heavyweights of psychoanalysis. It led to a model in which analyst and patient simply assumed that homosexuality was intrinsic, said Jack Drescher, a professor of psychiatry at Columbia University who knew Dr. Friedman and would later offer his own critiques of Dr. Friedman’s theory as new approaches to working with gay and lesbian patients emerged. © 2020 The New York Times Company

Keyword: Sexual Behavior
Link ID: 27229 - Posted: 05.05.2020

Christie Wilcox Sex might be biology’s most difficult enigma. The downsides of relying on sex to reproduce are undeniable: It takes two individuals, each of whom gets to pass on only part of their genome. Because these individuals generally have to get fairly intimate, they make themselves vulnerable to physical harm or infections from their partner. Asexual reproduction, or self-cloning, has none of these disadvantages. Clones can be made anywhere and anytime, and they receive the full complement of an individual’s genes. Yet despite all its benefits, asexual reproduction is the exception, not the norm, among organisms that have compartmentalized cells (eukaryotes). In plants, for example — which are somewhat known for their genetic flexibility — less than 1% of species are thought to reproduce asexually often. Among animals, only one out of every thousand known species is exclusively asexual. For centuries, biologists have pondered this apparent paradox. In 1932, the geneticist Hermann Muller, whose work on radiation-induced mutations would eventually garner a Nobel Prize, believed he had the answer. “Genetics has finally solved the age-old problem of the reason for the existence (i.e., the function) of sexuality and sex,” he boasted in The American Naturalist. He went on to explain, “Sexuality, through recombination, is a means for making the fullest use of the possibilities of gene mutations.” All Rights Reserved © 2020

Keyword: Sexual Behavior; Evolution
Link ID: 27210 - Posted: 04.24.2020

By Elizabeth Pennisi Ring-tailed lemurs have a peculiar habit of shaking their tails at potential rivals. New research shows that during the breeding season, a male’s trembling tail may instead be whisking sexy odors toward potential mates. The work is still preliminary, but chemical analyses have revealed the odor is a mixture of three chemicals that seem to pique a female’s interest. The new work “calls attention to the often underappreciated fact” that odors play an important role in primate societies, says Peter Kappeler, a primatologist at the University of Göttingen. Insects often use behavior-altering odors called pheromones to attract mates. So do mice. But biochemist Kazushige Touhara at the University of Tokyo wanted to know whether primates—including humans—use them as well. Some researchers say yes, but the existence of such “sex attractants” remains controversial. Ring-tailed lemurs (Lemur catta), named for their fluffy gray and black tails, are unusual among their fellow primates. Males have glands on their wrists that produce chemicals that quickly vaporize when exposed to air—similar to pheromones. They rub their wrists on their tails to transfer the odors before they vaporize, then shake their tails to broadcast the scent. For most of the year, these lemurs make bitter, leathery smelling chemicals used to keep other males at bay. But during the breeding season, they instead emit a sweet scent, Touhara says. He and his colleagues collected these secretions from the wrist glands with a tiny pipette and analyzed the chemical components. © 2020 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Chemical Senses (Smell & Taste)
Link ID: 27203 - Posted: 04.17.2020

By John Pickrell Joseph Schubert spends hours at a time lying in the dirt of the Australian outback watching for tiny flickers in the sparse, ground-hugging foliage. The 22-year-old arachnologist is searching for flea-sized peacock spiders, and he admits, he’s a little obsessed. But it wasn’t always so. Schubert grew up fearing spiders, with parents who were “absolutely terrified” of the eight-legged crawlers. “I was taught that every single spider in the house was going to kill me, and we should squish it and get rid of it,” he says. Then Schubert stumbled across some photographs of Australia’s endemic peacock spiders, a group named for the adult males’ vivid coloring and flamboyant dance moves aimed at wooing a mate (SN: 9/9/16; SN: 12/8/15). And he was hooked. “They raise their third pair of legs and dance around and show off like they are the most amazing animals on the planet, which in my eyes they are.” He decided to pursue a career in arachnology. And despite not quite having completed his undergraduate degree in biology, he’s begun working part time at Museums Victoria in Melbourne, and has already made a mark. Of the 86 known peacock spider species — each just 2.5 to 6 millimeters in length — 12 have been described by Schubert, including seven named in the March 27 Zootaxa. Those seven were found at a range of sites across Australia, including the barren dunes and shrublands of Victoria state’s Little Desert and the red rocks and arid outback gorges of Kalbarri National Park, north of Perth. © Society for Science & the Public 2000–2020

Keyword: Sexual Behavior; Evolution
Link ID: 27202 - Posted: 04.17.2020

By Elizabeth Pennisi Males resort to all sorts of desperate measures when fertile females are scarce, including banding together to guard a potential mate. Now, researchers have discovered that such bands of bottlenose dolphins may coordinate their actions with unique “popping” calls—the first evidence that animals other than humans can synchronize themselves using vocal signals. Humans often use vocal signals to coordinate actions, like marching and dancing, that reinforce unity and intimidate outside groups. The synchronized displays of other animals—like fireflies that light up at the same time—are thought to be competitive, showing off which male is the sexiest, rather than cooperative. In Shark Bay, off the coast Western Australia 800 kilometers north of Perth, groups of up to 14 male dolphins form lifelong alliances. Together, subsets of three keep close tabs on potential female mates, swimming, turning, and surfacing in unison to guard and herd them—one female at a time. Scientists watching this behavior noticed these males often emit a unique “popping” call, making series of two to 49 very short sounds, 10 per second, over and over. e dolphins popping The scientists dragged four underwater microphones behind a motorboat and recorded 172 instances in which multiple males were “popping” together (above). When the males pop alone, their timing and tempo varies. But when they pop together, they do it at the same time and at the same rate, suggesting they are using the sounds to enhance their cooperation, the team reports today in the Proceedings of the Royal Society B. This synchronized popping may be a threat, as it tends to make the female dolphin move closer to her male guards. But more importantly, the researchers say, it may help reinforce that the males need to act—and talk—as one to ensure they get their gal. © 2020 American Association for the Advancement of Science

Keyword: Sexual Behavior; Aggression
Link ID: 27156 - Posted: 04.01.2020