Chapter 2: Sex And Evolution1. The Truth About Female Desire episode 2 of 4 (2005) “Evolution”Source: BBC 4Length: 47 min, 40 secLink:http://video.google.com/videoplay?docid=5546317353756436157&ei=hkNySL_AKoyYrAKghqiBAw&hl=enDescription: “The Truth About Female Desire was a four part UK television series broadcast in 2005 which was a collaboration between the respected sex research centre The Kinsey Institute, London's Brunel University and Channel 4. In a major science event led by John Bancroft, six single girls share a dormitory at Brunel University, London, where scientists from the Kinsey Institute perform sexual experiments on them to determine the true nature of female desire. “ - MindhacksThis series features collaboration between the U.K. TV 4 and research scientists from the famous Kinsey Institute. Eight British women of various geographic and sexual backgrounds volunteer to have their bodies and minds probed, surveyed and tested in the name of science. Former Director of the Kinsey Institute, John Bancroft and his colleagues, Cynthia Graham and Eric Yamson spend an intimate week with these women in hopes of gaining a better understanding of and appreciation for the complexities of female sexuality. This episode focuses on the evolutionary roots of sexuality. Researchers use various experimental designs and techniques in an effort to understand the unconscious influences involved in attraction. Concepts/Keywords: sexual orientation, bisexuality,. Eric Yamson, sexual arousal, Kinsey scale, measuring sexual arousal, vaginal probe, John Bancroft, John Manning, mate selection, unconscious, universal principles of attraction, fertility cues, finger ratios, D2:D4 ratio, testosterone, estrogen, smelling attractiveness, reproductive fitness, pheromones, sweaty t-shirt experiment, sex hormones, and fetal hormonesSuggested Segments1. The matter at HAND: Unconscious processes involved in mate selection.Segment Cue: [13:30-20:42]Description: This segment demonstrates how adept women are at assessing attractiveness by merely holding hands with anonymous men on the other side of a curtain. Also discussed is the relationship between levels of circulating hormones in a fetus and the extent to which these chemicals will shape his body throughout life. Perhaps then, simply holding a man’s hand may give a potential mate valuable information related to his reproductive health or worth. Concepts/Keywords: Eric Yamson, attraction, mate selection, John Bancroft, vaginal probe, fertility cues, unconscious, finger ratio, and fetal hormone.2. Finger Ratios and SexualitySegment Cue: [20:44-24:20]Description: This segment highlights the relationship between the length of a man’s fingers and how attractive he is perceived. Surprisingly, the relationship between ring finger length and index finger length is a strong indicator of how much testosterone a particular man was exposed to during fetal development. John Manning’s research points out men with a greater ring finger to index finger ratio are anonymously selected as most attractive by females.Concepts/Keywords: John Manning, D2:D4 ratio, fetal hormones, mate selection, testosterone, estrogen, perception of attractiveness, unconscious and reproductive fitness.3. Smelling BeautySegment Cue: [24:22-27:12]Description: This segment examines the extent to which women can smell an attractive man. Dr. John Manning examines the relationship between women’s olfactory perception of men’s sweaty t-shirts and their attractiveness. Concepts/Keywords: smelling attractiveness, pheromones, John Manning, sweaty t-shirt experiment, and immune system.4. Beauty in MotionSegment Cue: [27:13-30:33]Description: This segment asks the question, “Can women ascertain a man’s attractiveness simply watching him move?” Eight women are asked to view dancing silhouettes and then rate how attractive they think these men really are based solely on this sliver of visual information. Concepts/Keywords: mate selection, attraction, unconscious, and sex hormones.2. Evolution: a journey into where we’re from and where we’re going. “WHY SEX?” episodeSource: PBShttp://www.pbs.org/wgbh/evolution/Length: 60 minLink: http://video.google.com/videoplay?docid=8590222764542986609&q=why+sex%3F&ei=HxF0SP2CC4jGrQLJpJyGCw&hl=enDescription: “In evolutionary terms, sex is more important than life itself. Sex fuels evolutionary change by adding variation to the gene pool. The powerful urge to pass our genes on to the next generation has likely changed the face of human culture in ways we're only beginning to understand.” –PBSConcepts/Keywords: sexual selection theory, sexual v asexual reproduction, Whiptail lizard, Meredith Small, Robert Rhinehock, sexual pathology, Red Queen hypothesis, sexual conflict, evolutionary fitness, mate competition and mate choice, reproductive strategies, behavioral traits, monogamy, extra pair copulations, paternity certainty, , gender roles, infanticide, cooperation, Bonobos, evolution of attraction, sweat t-shirt experiment, (MHC) major histocompatibility complex, evolutionary psychology, Geoffrey Miller, and evolution of the mind.Suggested Segments1. Sexual Selection TheorySegment Cue: [0:00-2:05]Description: Liam Neissen narrates/introduces one of Darwin’s lesser known, but equally important components of natural selection: sexual selection theory. Sex and genes –it turns out- drive behavior and evolution. 2. Whiptail Lizard & Asexual ReproductionSegment Cue: [2:42-4:53]Description: This segment showcases a southwest Texas, whip-tail lizard ‘round-up.’ This animal, unlike most, reproduces exclusively via an asexual process called pathogenesis. There are no males in this species; instead, females take turns mimicking stereotypical male mounting behavior; however, the ‘thrusting’ does NOT actually result in any copulation. Whiptail lizards, it turns out, are exact replicas of their mothers – clones! 3. Why Males?Segment Cue: [7:37-14:52]Description: Professor of Anthropology, Meredith Small kicks off this segment by suggesting “the biological imperative –as we all know – is to pass on genes. Most species on earth use sexual reproduction. Why do this?” Researcher, Robert Rhinehock, seeks an answer to this question by investigating tiny fish that live in small puddles in the hills of Senora, Mexico. His findings suggest those fish who reproduce sexually demonstrate more resistance to disease than those who reproduce asexually.4. Origin of Sexual ReproductionSegment Cue: [14:53-16:53]Description: This segment speculates as to the origin of sexual reproduction. Using a clever computer animation, Liam Neissen narrates a humorous, yet informative ‘just so’ story of how and why sexual reproducers evolved.5. Sexual ConflictSegment Cue: [16:54-22:49]Description: Why did Charles Darwin find the Peacock’s tail repulsive? Why are males typically larger than females? This segment offers an explanation to these and other questions related to the evolution of what appears to be conspicuous impediments. Professor’s Meredith Small and Geoffry Miller add illuminating commentary into Darwin’s ingenious theory of mate choice: sexual selection.6. Tail Lengthening ExperimentsSegment Cue: [22:50-25:09]Description: Mariam Petres discusses her ‘tail-lengthening’ research with peacocks. Her studies suggest that ‘bigger is usually better;’ that is, peacocks with artificially long tails (those with tails made longer with manual add-ons) have more mating opportunities. Petres data clearly supports Amos Zahavis’ handicap principle hypothesis. 7. MonogamySegment Cue: [25:10-27:37]Description: Stephen Emlend of Cornell University explains how the reproductive strategy of monogamy favors the offspring of songbirds. Only when both parents invest time and resources in their young, do these progeny live long and healthy enough to reproduce their own.8. Why do Females Cheat?Segment Cue: [27:38-29:27]Description: Why are some species monogamous while others favor polygamy? This segment discusses various reproductive strategies, exploring those evolutionary forces that encourage shared paternal investment, as well as those that threaten it. Despite their obvious social monogamy, song-birds occasionally cheat on their mate. Why, if monogamy, especially among song-birds, confers an advantage on the success of their offspring, would any species cheat?9. The Gender Bending JacanaSegment Cue: [29:28-31:37]Description: This segment discusses the concept of promiscuity and gender roles. Perhaps cheating is like mate insurance; that is, it gives the females a sort of ‘ace in the hole’. For a particular species of bird living among hungry predators, many eggs are eaten by hungry crocodiles. Unlike the female of most bird species, the South American Jacana (who is polyandrous), seems to care more about quantity than quality. This role reversal of sort, may explain why her behavior is more like that of a stereotypically male. In fact, the female Jacana is usually larger, more aggressive, and more promiscuous than males.10. Infanticide and CooperationSegment Cue: [31:38-40:10]Description: The relationship between promiscuity among female chimpanzees and paternity uncertainty is discussed. By mating with ‘all’ the males of a troop, a pregnant female chimpanzee encourages ‘all’ the males to assume he is the father. This in turn reduces the probability of violence and/or infanticide.This segment highlights the polar opposite social structures of our two closest living relatives: common chimps and pygmy chimps (Bonobos). How and why did violence, love making, and cooperation diverge among these primates. What do these species teach us about our evolutionary past? What, if anything, can we learn about our past as well as present sexuality? Primatologist, Richard Wrangam discusses the differences and similarities between our sexualities. 11. Evolution of the Human MindSegment Cues: [40:11-41:18 & 47:03-56:33]Description: This segment features evolutionary psychologist Geoffrey Miller. In it, he discusses his sometimes controversial, but always insightful, theory of mind. Miller suggests that like all physical traits, the human mind too must have evolved. Just as the peacock’s tail and beetles beautiful carapace has been sexually selected, so too has human mental traits. He contends, creativity, intelligence, art and dance are all solutions to the evolutionary problem of finding and attracting a reproductively fit mate. Miller views the evolution of the mind as an ‘entertainment center; a wooing device.’3. The Nature of Sex (1993) “Sex and the Human Animal”Source: PBS Nature SeriesLength: 60 minLink: http://www.pbs.org/wnet/nature/sex/human-animal.htmlDescription: “Was it his eyes or hair? Was it her nose or smile? People don't always know what attracted them to a potential mate. But it is certain that the roots of that attraction reach far back into the human past, when our ancestors were foraging across some African plain. As explained in SEX AND THE HUMAN ANIMAL, Part 4 of NATURE's THE NATURE OF SEX, our sexual behavior evolved to improve the odds that our offspring would survive to have their own children.” -PBSConcepts/Keywords: shared evolutionary past, prehistory of humans, concealed ovulation, estrus, male and female size ratio, genital morphology, sexual practices, sexual display, jealousy, cuckoldry, mate guarding, nursing, incest taboo, and Bonobos.Suggested Segments1. Shared evolution and ancestral sexualityLength: 9 min, 48 secLink: http://www.youtube.com/watch?v=yd3JGhuMmrc&feature=related2. Universality of Sexual SignalsLength: 10 min, 12 secLink: http://www.youtube.com/watch?v=lRRqCz7SIZI&feature=relatedDescription: This segment discusses the concept of sexual selection. Outlined eyes and red lips, human signals of exaggerated sexual display is the human equivalent of a peacock’s tail. Men of the Wadabi Tribe in West Africa ready themselves for a ceremonial beauty contest or a bride market in Morocco plays host to men and women who look to impress one another with honest displays of sexual worth. A bower bird builds an enormous and elaborate structure to get a females attention. A olive baboon spends hours patiently observing a mother and child. All are evolved techniques aimed at showcasing and evaluating valuable information about another’s potential reproductive worth.3. Sexual jealousy across speciesLength: 10 min, 23 secLink: http://video.google.com/videoplay?docid=-272676531048594630&q=the+nature+of+sex&ei=xnFySM6IK4WqrwKqiPCvAw&hl=enDescription: This segment highlights the importance of jealously. Mate guarding as it is commonly referred to in the scientific community, has evolved as a strategy to ensure paternity. A male who keeps the most watchful eye – so to speak - on his mate, reduces his risk of being cuckolded by a rival male. From humans to leopard seals, perhaps all sexually reproducing species use some type of mate guarding technique to improve their odds of paternity.4. Nursing: A burdensome investmentSegment Cue: [1:00-5:32] Link: http://video.google.com/videoplay?docid=-272676531048594630&q=sex+and+the+human+animal&ei=soReSOvAEoP8rQKJrYWWCA&hl=enDescription: This segment highlights the expensive and important role mothers play before, during and after pregnancy. That having offspring is such a costly endeavor, most female species are extremely picky of potential fathers. Whether human or monkey, mate preferences drive reproduction.5. Incest TabooSegment Cue: [5:33-6:38]Link: http://video.google.com/videoplay?docid=272676531048594630&q=sex+and+the+human+animal&ei=soReSOvAEoP8rQKJrYWWCA&hl=enDescription: This segment introduces the concept of an incest taboo. Nearly universal in its social denunciation, researchers now believe there may be an inborn predisposition across primates that discourage sex with members considered family. An examination of Israeli Kibbutzim highlights the significance and extent to which this aversion is at work.6. Are we really that different?Segment Cue: [0:00-3:00]Link: http://video.google.com/videoplay?docid=8281368105049444227&q=sex+and+the+human+animal&ei=soReSOvAEoP8rQKJrYWWCA&hl=enDescription: This segment examines art, social hierarchy and intelligence, in an attempt to demonstrate the differences between human sexuality and the sexuality of all other living species. However, by studing the Bonobo chimpanzees, our closest living relative, we are given a poignant reminder that human sexuality has been, and perhaps, always will be, intimately linked to our primate past.4. The Science of the Sexes episode 2 of 2 “Different by Design”Source: Discovery Channel and BBC 4Length: 50 minLink:http://video.google.com/videoplay?docid=-5453608011322025140&q=different+by+design&ei=eE9hSKWxDpy2rALv863YAQ&hl=enDescription: “This definitive trip around male and female anatomy confirms what our bodies know, but we often forget: men and women are made for each other! Listen, but try not to blush, as intimate portraits and real-life situations are combined with scientific analysis to show that from conception to old age, our bodies grow, adapt, compliment and support each other. Take a look at sexual progression from adulthood to old age. From sexual attraction to physical stamina, every angle is explored. Watch as identical twins are put to a real-life test of sexual attraction. And, thanks to some computer animation and unique endoscopic filming techniques, you'll see what goes on inside their bodies when they're aroused. Study the mechanics of intercourse using an MRI scanner and get a close-up look at the peaks and valleys of brain activity in the two sexes when processing emotion. An expert debate on the issue of nature versus nurture prompts an intimate look at two teenagers – one boy and one girl – on different continents. Who has the advantage? Follow Dr. Helen Fisher, an anthropologist and world-renowned expert on gender differences, to Africa to determine if the development of the male and female brain could be linked to our evolutionary past. The latest research on spatial ability between the sexes is revealed, and there's an unlikely connection: testosterone levels and finger length!” -BBCConcepts/Keywords: starfish, aphids, bacteria, Helen Fisher, why are there two sexes?, mating, Darwin, genetic variety, sexual reproduction, reproductive organs, sex cells, eggs, ovaries, fertility, embryo, sperm cells, puberty, testes, twins, pheromones, immune compatibility, thinking about sex, turn-ons, arousal, parasympathetic nerves, vaso-congestion, physiology of sex, sympathetic, s, nervous system, brain, MRI scan, uterus, sperm delivery, testicle bathing, testosterone, estrogen, virilization, gender differences, gender role, spatialization, hemispherization, emotion, reading faces, multi-tasking, hypothalamus, menopause, vaso- dilation, Hadsa tribe, grandmother hypothesis, x chromosome, y chromosome, and mosaics.5. Dr. Tatiana’s Sex Advise to All Creation Source: BBC 4Length: 60 minLink: http://www.channel4.com/Description: It is perhaps the most original science documentary ever made. Dr Tatiana's Sex Advice to All Creation is an all-singing, all-dancing musical. No joke: there are 14 original songs, including the hermaphrodite song and the female promiscuity song (which features the refrain, "I want to do it again, I want to do it again, my mother always said you can't have too many men"). And that's not all. Dr Tatiana--played by a white-leather-clad Olivia Judson--interviews scientists, chases wild banana slugs and elephant seals, dispenses sex advice in her clinic, and conducts a Jerry-Springer-style TV show within the TV show. But where Springer's guests are troubled humans, Dr Tatiana's are penis-fencing flatworms, sexless rotifers, and fruit flies that use drugs to keep their mates faithful. -http://www.drtatiana.com/show.shtmlSuggested Segments1. Sex for PleasureLength: 1 min, 25 secLink: http://www.youtube.com/watch?v=ciIsaVNBLbUDescription: This short video segment features BBC’s own in-sex-pert, Dr. Tatiana [aka: Olivia Judsen}. In it, she highlights the ubiquity of randiness by introducing some masturbating lizards, oral sex prone fruit flies and some toads with foot fetishes.2. Sacrifice for LoveLength: 3 min, 33 secLink: http://www.youtube.com/watch?v=4ZUn3V61BdA&feature=relatedDescription: This segment features Dr. Tatiana [aka: Olivia Judson]. In it, she discusses one of the strangest examples of mate guarding: the honey bee. It turns out, after a male copulates with the queen bee, his genitals fall off! By plugging her reproductive opening with his exploding genitalia, the male honey bee increases the likelihood of paternity.3. Competing for Love: “Hunks V Wimps” Length: 4 min, 28 sec Link: http://video.google.com/videoplay?docid=-794433631776605974&q=dr.+tatiana%27s+sex+advise&ei=aXZySM7xA4T-qgLP2MGJDw&hl=en Description: In this video segment, Dr. Tatiana discusses the relationship between male genitalia and reproductive success. The evolutionary arm’s race between male courtship strategies and female expectations of genetic potential is highlighted. 6. What Females Want and Males Will Do (2008) Source: PBS Nature SeriesLength: 120 minLink: http://www.pbs.org/wnet/nature/episodes/what-females-want/what-females-want-introduction/828/Description: “What Females Want and Males Will Do explores the evolution of sexual strategies and what makes certain species winners and losers in the mating game. Courtship drives evolution by controlling whose genes are passed on to the next generation, and intense competition gives rise to a wide array of dazzling displays and impressive ornamentation.From spiders that dance and monkeys that drum in the name of love, to female geladas that seek male partners with hot, red chest patches — this program about sexual selection explores the unique behaviors and special adaptations that determine how animals pick their mates, and how these selections affect future generations. In some species, the normal rules of mating are turned on their head, such as the feisty female topi antelope champing at the bit to have sex with an aloof male or bonobo males practicing free love.Scientists around the world are making amazing new discoveries about the complex nature of courtship and competition throughout the animal kingdom. It’s sexual education that takes us way beyond the “birds and the bees.” -PBSSuggested Segments1. Gelato Baboons & Sexual ConflictLength: 2 min, 26 secLink: http://www.pbs.org/wnet/nature/episodes/what-females-want/bachelor-geladas-challenge-chewbacca/839/Description: “This segment features biologist Chadden Hunter, as he observes a troop of geladas, close cousins of baboons. He found that in gelada society the females make all the decisions about mating, even though the males are twice their size. Sacca and Win, the females of the troop, might just depose him in favor of another male.” – PBS2. Wooing Sage Grouse with a Robot Length: 3 min, 54 sec Link: http://www.pbs.org/wnet/nature/episodes/what-females-want/sage-grouse-fembot/840/ Description: Biologist, Gail Patricelli, uses state of the art technology to learn more about how female sage grouses in Wyoming choose a mate. Out on the lek, an area of land designated by the sage grouses for courtship, Gail introduces a ‘fembot’ to measure the courtship ritual.3. “Spider Courtship Dance” Length: 6 min Link: http://video.google.com/videosearch?complete=1&hl=en&q=what%20females%20want&um=1&ie=UTF-8&sa=N&tab=wv# Description: “With a high-speed camera and vibrometer in his toolkit, researcher Damian Elias, is able to pick up on a courtship ritual few have ever seen before. He's discovered that male jumping spiders actually perform an elaborate dance — with coordinated vibrations, no less — to woo potential partners.” –PBS7. Attenborough in Paradise 1 of 7 episodes (1996) “Paradise Birds of New Guinea”Source: BBCLength: 55 min, 34 secLink: http://video.google.com/videoplay?docid=-5253625995741461037Description: Naturalist, Sir David Attenborough takes the viewer on a spectacular journey into the rustic and picturesque land of New Guinea. There, we meet a diverse array of winged creatures known as the Birds of Paradise. Showcased are the birds mating rituals, display techniques and reproductive strategies.8. Life of Birds 6 of 10 episodes (2008) “Signals and Songs”Source: PBSLength: 60 minLink: http://www.pbs.org/lifeofbirds/Description: This video from the Life of Birds - is a multi-series documenting dozens of birds across 42 countries – is the sixth of ten episodes. Naturalist and film maker, David Attenborough hosts this intimate journey into the wildest of habitats. The sex lives of various winged animals are examined in great detail. That many of the species use courtship techniques similar to those of humans – songs, dances, adornments, and gifts – this series presents the learner with an excellent lens through with to think about human sexuality.Suggested Segments1. Superb Lyre Bird Length: 2 min, 54 secLink: http://www.youtube.com/watch?v=VjE0Kdfos4YDescription: This segment from the Life of Birds documentary by famous nature reporter, David Attenborough, features the sexy and talented Lyre bird. Listen carefully as this talented creature mimics the sounds of other birds, car alarms and chain saws. This is a truly remarkable video clip, demonstrating the amazing and unconscious vocal repertoire of a otherwise ordinary bird. 2. Plumed Bird of ParadiseLength: 4 min, 01 secLink: http://www.youtube.com/watch?v=cEh-zclVo44Description: This segment introduces the amazing and beautiful plumed Bird of Paradise. This magnificent animal puts on an elaborate courtship display in search of mating partners. Watch in awe as this skilled creature puts on a ‘rock star’ performance, all in an unconscious effort to pass on his genes.3. Natures Carpenter: The Bower BirdLength: 4 min, 12 secLink: http://www.youtube.com/watch?v=GPbWJPsBPdADescription: Meet one of nature’s most skilled carpenters. Taken from one of David Attenborough’s nature documentaries, we are introduced to the dedicated builder, the Bower bird. His brilliant and elaborate constructions, called Bowers, are unconscious sexual displays. This otherwise ordinary bird, demonstrates his reproductive worth to a potential mate by building beautifully ornate and highly elaborate structures.4. Natures Snazzy Dressers: PheasantsLength: 3 min, 24 secLink: http://www.youtube.com/watch?v=gqsMTZQ-pmEDescription: David Attenborough introduces several species of Pheasant. This segment features the power of sexual displays. With impressive iridescent waddles and giant tail feathers, natures most beautiful and extravagant costumes demonstrate the double-edge sword of conspicuous and often exaggerated display. Brilliant colors and expansive trains may attract the opposite sex; but they most certainly attract hungry predators.9. Flying Casanovas (2001)Source: PBS Nova SeriesLength: 60 minLink: http://www.pbs.org/wgbh/nova/bowerbirds/Description: “When a European naturalist first found small thatched huts in the rain forest of New Guinea in the late 19th century, he thought they were homes of an unknown tribe of pygmies. In front of each entrance, there was a neat lawn of moss flanked by decorative beds of pink blossom, orange fruits, and shining beetle wings. In fact, the builders were not people but a species of bowerbird. In "Flying Casanovas," host David Attenborough leads viewers into this little-known world of avian architecture.” –PBS Nova10. Life in the Freezer episode 3 of 6 (2007) “The Race to Breed” Source: BBCLength: 30 minLink: http://www.bbc.co.uk/programmes/b007bnhmDescription: A natural history of Antarctica presented by Sir David Attenborough. It's summer in Antarctica, and with 24-hour daylight the race to breed is on as two million fur seals crowd the beaches of South Georgia. When the pups are born, ferocious bulls attack any intruders who challenge their females. Meanwhile, Chinstrap penguins cross glacial streams and climb near vertical cliffs to feed their chicks as formidable leopard seals lurk.Suggested Segment1. Elephant Seal and His HaremLength: 5 min, 06 secLink: http://www.youtube.com/watch?v=fQI5KUfM2xcDescription: This segment features nature reporter David Attenborough as he discusses the mating strategy of the elephant seal. Just one male keeps a harem of nearly 100 females. To keep control, the harem master must keep a vigilant eye on his partners, least be cuckolded by a nearby rival hoping to poach one of the alpha seal’s mates.11. Homosexality in Nature Source: SexplorationsLength: 8 min, 20 secLink: http://www.youtube.com/watch?v=VUwza5Grxos&feature=relatedDescription: Researcher and author, of Biological Exuberance, Bruce Bagemihl, believe same-sex relationships occur in 15-30% of all the 1 million species that exist on the earth. In this segment, Dr. Bagemihl talks about a variety of animals he and others have observed engaging in homosexual behavior. He contends, in contrast to most evolutionary theories, homosexual interactions can have multiple meanings and can serve many purposes.12. Bizarre BreedingSource: BBC Weird NatureLength: 30 minLink: http://www.veoh.com/videos/v65795098AsPbzSw?rank=31&Description: This show chronicles the ever important and sometimes strange plight to reproduce. From cannibalistic insects to mice that actually copulate to death! No matter the approach to reproduction, or the organism participating, courtship is merely about getting one’s genes into the next generation.Concepts/Keywords: dancing scorpions, bower birds, nuptials, courtship displays, reproductive fitness, mice, sacrifice for sex, praying mantis, cannibalism, genes, gender, reef fish, sex changing fish, sex slugs, hermaphrodites, mating chains, Chinese fighting fish, bubble nests, foam nesting frogs, eggs, leaping leaf laying tetras, synchronized swimming, paternal investment, sub-dermal gestation, devoted bull frog fathers, Siberian dwarf hamster and male midwifery, birth, umbilical cord, sea horses, brood pouch, male pregnancy, contractions, extended childcare, Asian musk shrew