Animal Sexual Behavior: Let’s know about the Animal Sexual Behavior. Animal sexual behavior takes many different forms, including within the same species . Common mating or reproductively motivated systems include monogamy , polygamy , polyandry , polygamy , and mating . Other sexual behaviors may be reproductively motivated (eg sex due to explicit coercion or coercion and situational sexual behavior ) or non-reproductively motivated (eg interspecific sexuality , sexual arousal from objects or places, dead sex with animals ,homosexual sexual behavior and bisexual sexual behavior).
When animal sexual behavior is reproductively motivated, it is often referred to as mating or copulation ; For most non-human mammals , mating and copulation occur in oestrus (the most fertile period in the reproductive cycle of a mammalian female), increasing the chances of successful impregnation . [1] [2] The sexual behavior of some animals involves competition , sometimes fighting, between several males . Females often choose males for mating only when they appear strong and able to defend themselves. The male who wins the fight may also have a chance to mate with a larger number of females and so will pass on his genes to his offspring. (Animal Sexual Behavior)
Historically, it was believed that only humans and a small number of other species performed sexual functions other than reproduction, and that animal sexuality was instinctive and a simple ” stimulus-response ” behavior. However, in addition to homosexual behaviors, many species masturbate and may use objects as tools to help them do so . Sexual behavior may be more strongly tied to the establishment and maintenance of complex social bonds in a population that support its success by non-reproductive methods. Both reproductive and non-reproductive behavior may be related to an expression of dominance over another animal or survival in a stressful situation (such as sex under pressure or coercion).
mating system
In sociobiology and behavioral ecology , the term “reproductive system” is used to describe the ways animal societies are structured in relation to sexual behavior. The mating system specifies which males mate with which females and under what circumstances. There are four basic systems:
| Four basic mating systems | ||
|---|---|---|
| single woman | multiple women | |
| solo male | single-marriage | polygamy |
| multiple males | Polygamy | polygamy |
single-marriage
Monogamy occurs when one male mates exclusively with one female. A monogamous mating system is one in which individuals form long-lasting pairs and cooperate to produce offspring. These pairs may last a lifetime, as in pigeons , [6] or it may occasionally change from one mating season to another, as in emperor penguins . [7] Unlike tournament species , these pair-bonding species have male aggression, competition, and little sexual dimorphism .level is reduced. Zoologists and biologists now have evidence that monogamous pairs of animals are not always sexually exclusive. Many animals that form pairs and produce offspring regularly engage in sexual activity with additional mate partners. This includes previous examples, such as the swan. Sometimes, these extra-pair sexual activities lead to offspring. Genetic tests often show that some offspring raised by a monogamous pair comes from female mating with an extra-pair male partner. These discoveries have prompted biologists to adopt new ways of talking about monogamy. According to Ulrich Reichardt (2003):
Social monogamy refers to the social life arrangement of a male and female (for example, shared use of a territory, behavioral indicators of a social pair, and/or closeness between male and female), without any sexual contact or reproductive patterns. Mentioned. In humans, social monogamy takes the form of monogamous marriage. Sexual monogamy is defined as an exclusive sexual relationship between a woman and a man based on the observation of a sexual relationship. Finally, the term genetic monogamy is used when DNA analysis can confirm that a female-male pair breeds exclusively with each other. A combination of words indicates instances where the levels of relationship coincide, for example, social and social monogamous monogamy describe social and sexual, and social and genetic monogamous relationships respectively.
Whatever makes a pair of animals socially monogamous does not necessarily make them sexually or genetically monogamous. Social monogamy, sexual monogamy, and genetic monogamy can occur in various combinations. (Animal Sexual Behavior)
Social monogamy is relatively rare in the animal kingdom. The actual incidence of social monogamy varies greatly among different branches of the evolutionary tree. More than 90% of avian species are socially monogamous. [10] [16] This is in contrast to mammals. Only 3% of mammalian species are socially monogamous, although up to 15% are primate species. [10] [16] Social monogamy has also been observed in reptiles, fish and insects.
Sexual monogamy is also rare in animals. Many socially monogamous species engage in extra-pair copulation, making them sexually non-monogamous. For example, while more than 90% of birds are socially monogamous, “on average, 30% or more of the baby birds in any given nest [are] reared by an individual other than the resident male.” [17] Patricia Adair Goatti has estimated that of the 180 different species of socially monogamous songbird, only 10% are sexually monogamous. [18]
The incidence of genetic monogamy, as determined by DNA fingerprinting, varies widely among species. For some rare species, the incidence of genetic monogamy is 100%, with all offspring genetically related to socially monogamous pairs. But genetic monogamy is surprisingly low in other species. Barash and Lipton Note:
The highest known frequency of extra-pair copulation is found in fairy-writers, the furry tropical creatures technically known as Malurus splendens and Malurus sineus . More than 65% of all fairy-rain chicks are bred by males outside the alleged breeding group. [16] p. 12
Such low levels of genetic monogamy have surprised biologists and zoologists, forcing them to rethink the role of social monogamy in evolution. They can no longer assume that social monogamy determines how genes are distributed in a species. The lower the rate of genetic monogamy between socially monogamous pairs, the less role social monogamy plays in determining how genes are distributed among offspring.
polygamy
The term polygamy is an umbrella term generally used for non-monogamous intercourse. As such, polygamous relationships can be polygamous, polyandrous, or polygamous. In a small number of species, individuals may exhibit polygamous or monogamous behavior depending on environmental conditions. An example is the social wasp Apoica flavisima . In some species, polygamy and polyandry are exhibited by both sexes in the population. Polygamy in both sexes has been observed in the red flour beetle ( Tribolium castaneum ). Polygamy is also seen in several Lepidoptera species, including Mithymna unipuncta (the true armyworm moth ). (Animal Sexual Behavior)
A tournament species is one in which “mating is highly polygamous and involves high levels of male–male aggression and competition.” [20] Tournament behavior is often associated with high levels of sexual dimorphism, examples of species including chimpanzees and baboons. Most polygamous species present high levels of tournament behavior, with a notable exception being bonobos. (Animal Sexual Behavior)
polygamy
Polygamy occurs when one man has exclusive sexual intercourse with several women. In some species, especially those with harem-like structures, only one of the few males in a group of females will mate. Technically, in sociology and zoology, polygamy is defined as a system in which a man is in a relationship with more than one woman, but women are primarily tied to a single man. Should the active male be kicked out, killed, or otherwise removed from the group, in many species the new male will ensure that reproductive resources are not wasted on the young of the other male. [21] The new male can achieve this in several different ways, including:
- Competitive infanticide: In lions, hippopotamuses, and some monkeys, the new male will kill the offspring of the previous alpha male, making their mothers more receptive to his sexual advances as they are no longer feeding. To prevent this, many female primates display ovulation signals among all males, and show position-dependent receptivity. [22]
- Harassment to abort: Among wild horses and baboons, the male will “systematically harass” pregnant females until they miscarry.
- pheromone based spontaneous abortion
- In some rodents such as rats, a new male with a distinct odor will spontaneously fail to implant recently fertilized eggs to pregnant females. It does not require contact; It is mediated only by smell. This is known as the Bruce Effect.
Von Hartmann specifically described the mating behavior of the European pied flycatcher as gradual polygamy. [23] Within this system, males leave their home territory when their primary female lays her first egg. Males then create a second territory, possibly to attract a secondary female for breeding. Even when they are successful in obtaining a second mate, the males usually return to the first female specifically to provide for her and her offspring. [24]
Polygamous mating structures are estimated to occur in 90% of mammal species. [25] Since polygamy is the most common form of polygamy among vertebrates (including humans, to a lesser extent), it has been studied far more extensively than polyandry or polygamy.
Polygamy
Polyandry occurs when a female has exclusive mating rights with multiple males. In some species, such as the redlip blenies, both polygamy and polyandry are observed. [26]
In some deep sea anglerfish the males are much smaller than the females. When they find a female they bite into her skin, releasing an enzyme that digests the skin of her mouth and her body and fuses the pair to the blood-vessel level. The male then gradually atrophies, losing first his digestive organs, then his brain, heart and eyes, ending up as a pair of gonads, which release spermatozoa in response to hormones into the female’s bloodstream that Indicates egg release. This extreme sexual dimorphism ensures that, when the female is ready to lay eggs, she has a mate immediately available. [27] A single anglerfish female may “mate” with multiple males in this way.
polygamy
Polygamy occurs when several males have indiscriminate intercourse with multiple females. The number of males and females should not be the same, and in the vertebrate species studied so far, there are usually fewer males. Two examples of systems in primates are the multiple mating chimpanzees and the bonobos. These species live in social groups consisting of many males and many females. Each female mates with several males, and vice versa. Among bonobos, the amount of sexuality is particularly striking because bonobos use sex to reproduce, while simultaneously reducing social conflict. [28] This mutual involvement is the approach commonly used to breed animals, and is probably the “native fish mating system”. [4] : 161Common examples are forage fish, such as hermits, which form huge mating shoals in shallow water. The water turns milky with sperm and is wrapped with millions of fertilized eggs at the bottom. [4] : 161
Parental investment and reproductive success
Female and male sexual behavior differ in many species. Often, males are more active in initiating mating, and wear more distinctive sexual ornamentation such as horns and colored feathers. This is the result of anisogamy, where the sperm is smaller and much less expensive (energetic) than the egg. This difference in physiological costs means that males are more limited by the number of their mates, while females are limited by the quality of their mates’ genes, a phenomenon known as Bateman’s theory. [29] Many women also have an additional reproductive burden, as parental care often falls primarily or exclusively on them. Thus, females are more limited in their potential reproductive success. [30]In species where males incur higher breeding costs, such as seahorses and jacanas, the role is reversed, and females are larger, more aggressive, and more brightly colored than males.
In bisexual animals, the cost of parental care can be distributed equally between the sexes, such as in earthworms. In some planetary species, sexual behavior takes the form of penis fencing. In this form of copulation, the individual who enters the second with the first sex, forces the second to be female, thus bearing the majority of the cost of reproduction. [31] After mating, banana slugs sometimes bite off their partner’s penis as an act of sperm competition known as apophalation. [32]This is costly because they must heal, and expend more energy that can function as male and female. One hypothesis suggests that these slugs may be able to compensate for the loss of male function by directing energy that would have been exerted towards it towards female work. [33] In Gray Slug, a spectacular performance, where mates suspend themselves high above the ground by a slime thread, exchanging cost clues, ensuring none of them can refrain from taking on the cost of the egg carrier Huh.(Animal Sexual Behavior)
weather
Many animal species have specific mating (or breeding) periods such as (seasonal reproduction) so that offspring can be produced or born at the optimum time. In marine species with limited mobility and external fertilization such as corals, sea urchins and clams, the timing of normal spawning is the only externally visible form of sexual behavior. In areas with consistently high primary production, some species have a series of breeding seasons throughout the year. This is the case with most primates (which are mainly tropical and subtropical animals). Some animals (opportunistic breeders) breed depending on conditions in their environment other than the time of year.
mammals
Mating seasons are often associated with behavioral changes including changes in herd or group structure and territorialism among individuals. These can be annuals (such as wolves), biennials (such as dogs) or more frequently (such as horses). During these periods, females of most mammalian species are mentally and physically more receptive to sexual advances, a period scientifically described as oestrus, but usually “in season” or “in heat”. ” is described as. Sexual behavior may occur outside of oestrus, [35] and such acts are not necessarily harmful. [36]
Some mammals (such as domestic cats, rabbits and camels) have what are called “induced eggs”. For these species, the female ovulates due to external stimulation during or just before mating, rather than ovulating cyclically or spontaneously. Stimulants causing induced ovulation include coitus, sexual behavior of sperm and pheromones. Domestic cats have a penile spine. When a cat’s penis is withdrawn, the spine rakes the walls of the woman’s vagina, which can lead to ovulation.
amphibian
For many amphibians, an annual reproductive cycle is in place, usually controlled by ambient temperature, rainfall, surface water availability and food supply. This breeding season is emphasized in temperate regions, in boreal climates the breeding season is usually concentrated to a few days in spring. Some species, such as Rana clamitans (green frog), guard their territory from June to August. To protect these territories, they use five vowels. [39]
fish
Like many coral reef inhabitants, clownfish spawn around the time of the full moon in the wild. In a group of clownfish, there is a strict dominance hierarchy. The largest and most aggressive female is found at the top. Only two clownfish in a group, a male and a female, reproduce through external fertilization. Clownfish are hermaphrodite, meaning they first develop into males, and when they mature, they become females. If a female clownfish is removed from the group, as if by death, one of the largest and most dominant males will become a female. The remaining men will go up one rank in the hierarchy.
Inspiration
Various neurohormones stimulate sexual desire in animals. In general, studies have suggested that dopamine is involved in sexual arousal motivation, oxytocin and melanocortin in sexual attraction, and noradrenaline in sexual arousal. [40] Vasopressin is also involved in the sexual behavior of some animals. [41]
Neurohormones in the Mating System of Voles
The reproductive system of prairie voles is single; After mating, they form a lifelong bond. In contrast, montane voles have a polygamous mating system. When montane voles mate, they do not form any strong attachments, and are separated after copulation. Studies on the brains of these two species have found that it is the two neurohormones and their respective receptors that are responsible for these differences in mating strategies. Male prairie voles release vasopressin after copulation with a mate, and then an attachment to their mate develops. Female prairie voles release oxytocin after copulation with a mate, and thus develop attachment to their mate.
Neither male nor female montane voles release high amounts of oxytocin or vasopressin when they mate. Even when injected with these neurohormones, their mating system does not change. Conversely, if prairie voles are injected with neurohormones, they can form a lifelong attachment, even if they have not mated. It is believed [ by whom? ,that the different neurohormone response between the two species is due to differences in the number of oxytocin and vasopressin receptors. Prairie voles have a higher number of oxytocin and vasopressin receptors than montane voles, and are therefore more sensitive to those two neurohormones. It is believed that it is the amount of receptors, rather than the amount of hormones, that determines the mating system and bond-building of any given species.
Oxytocin and rat sexual behavior
Mother rats experience a postpartum estrus that makes them highly motivated to mate. However, they also have a strong motivation to protect their newborn puppies. As a result, the mother rat invites the male to the nest but at the same time becomes aggressive towards them to protect her young. If the mother rat is given injections of an oxytocin receptor antagonist, they no longer experience these maternal stimuli. [42]
Prolactin affects social bonding in rats. [42]
Oxytocin and Intimate Sexual Behavior
Oxytocin plays a similar role in non-human primates as it does in humans.
Grooming, sex and cuddling frequencies correlated positively with oxytocin levels. As oxytocin levels increase, so does sexual motivation. While oxytocin plays a major role in parent-child relationships, it also plays a role in adult sexual relationships. Its secretion affects the nature of the relationship or if there will even be a relationship. (Animal Sexual Behavior)
Studies have shown that monkeys in monogamous relationships have more oxytocin than those in monogamous relationships. In addition, couples’ oxytocin levels correlate positively; When the oxytocin secretion of one increases, the other also increases. Higher levels of oxytocin are related to monkeys expressing more behaviors such as cuddling, grooming and sex, while lower levels of oxytocin reduce motivation for these activities. (Animal Sexual Behavior)
Research into the role of oxytocin in the brain of animals suggests that it plays a lesser role in loving and affectionate behavior than previously thought. “When oxytocin was first discovered in 1909, it was mostly thought to affect a mother’s labor contractions and lack of milk. Then, in the 1990s, research with prairie voles found that Giving him a dose of oxytocin created a bond with his future partner (Azar, 40).” Oxytocin has since been regarded by the media as the sole player in the “love and mating game” in mammals. However, this view is proving to be incorrect, as “most hormones do not directly affect behavior. Rather, they affect thinking and feelings in a variable way (Azar, 40).”[४४] [४५] [४६] [४७] [४८] [४९] [५०]
Pleasure
It is often assumed that animals do not have sex for pleasure, or alternatively that humans, pigs, bonobos (and perhaps one or two more species of dolphins and primates) are the only species that do. This is sometimes referred to as “animals only mate for reproduction”. This view is considered a misconception by some scholars. [51] [52] Jonathan Balcombe argues that the prevalence of non-reproductive sexual behavior in some species suggests that sexual arousal is pleasurable. He also points to the presence of a clitoris in some female mammals and evidence of female mating in primates. [53] On the other hand, it is impossible to know the subjective emotions of animals, [40] and the notion that non-human animals experience emotions similar to humans is a controversial topic.[५४] [५५] [५६] [५७]
The Danish Animal Ethics Council report of 2006, [58] which examined current knowledge of animal sexuality in the context of legal questions relating to sexual acts by humans, made the following comments, which mainly pertain to domestic common animals. :
Even though the developmental purpose of mating may be called reproduction, it is not actually the creation of offspring that originally caused them to mate. It is possible that they orgasm because they are motivated for actual copulation, and because it is associated with a positive experience. It is therefore reasonable to assume that there is some kind of pleasure or satisfaction associated with the act. This assumption is corroborated by the behavior of males, which in the case of many species are drawn to work, especially if the female animal is in the fly, gaining access to female animals, and for breeding purposes. It is used for men who become very eager to collect sperm after they have removed the equipment associated with the collection. , , , There is nothing in the anatomy or physiology of female mammals that contradicts that stimulation and orgasm of the sex organs can be a positive experience. For example, the clitoris functions in the same way as in females, and scientific studies have shown that stimulation of the clitoris in relation to conception (among other species) on cows and mares improves reproductive success, as it transports improves. spermatozoa due to contraction of the internal genitalia. This probably applies to female animals of other animal species as well, and contractions are seen in the internal genitals such as during mating for females. It is therefore reasonable to assume that mating can be associated with a positive experience for female animals. And scientific studies have shown that stimulation of the clitoris on cows and mares in relation to conception (among other species) improves reproductive success, as it improves transport. spermatozoa due to contraction of the internal genitalia. This probably applies to female animals of other animal species as well, and contractions are seen in the internal genitals such as during mating for females. It is therefore reasonable to assume that mating can be associated with a positive experience for female animals. And scientific studies have shown that stimulation of the clitoris on cows and mares in relation to conception (among other species) improves reproductive success, as it improves transport. spermatozoa due to contraction of the internal genitalia. This probably applies to female animals of other animal species as well, and contractions are seen in the internal genitals such as during mating for females. It is therefore reasonable to assume that mating can be associated with a positive experience for female animals. And contractions are seen in the internal genitals like during intercourse for women too. It is therefore reasonable to assume that mating can be associated with a positive experience for female animals. And contractions are seen in the internal genitals like during intercourse for women too. It is therefore reasonable to assume that mating can be associated with a positive experience for female animals.
koinophilia
Koinophilia is the love of “normal” or phenotypically normal (Greek , koinos , meaning “common” or “common”). [59] The term was introduced to the scientific literature in the 1990s, and refers to the tendency of animals looking for a mate not to attribute any unusual, strange, or distracting features to the mate. [59] Similarly, animals preferentially choose mates with less fluctuating heterogeneity. [60] However, the sexual ornamentation of animals may have evolved through runaway selection, which is driven by (usually female) selection for non-standard traits. [61]
interpretation bias
The field of study of sexuality in non-human species was long taboo. [62] In the past, researchers sometimes failed to observe, misclassify, or misrepresent sexual behavior that did not meet their preconceptions—to support their bias into what is now stereotyped sexual behavior. as will be described. An example of ignoring behavior related to the description of giraffe mating:
Nine out of ten pairs occur among males, so “[e] the very male that a female sniffed was reported as sex, while intercourse with anal sex was only ‘associated’ among males [as [classified] was dominance, competition or congratulation.” [62]
In the 21st century, liberal social or sexual ideas are often projected onto animal subjects of research. Popular discussions of bonobos are frequently cited examples. Current research often echoes ideas such as the Museum of Natural History at the University of Oslo, which held an exhibition on animal sexuality in 2006:
Many researchers have described homosexuality as completely different from sex. They must realize that animals can have sex with anyone when they want and without considering the ethical principles of a researcher. [62]
Other animal movements can be misinterpreted because of the frequency and context in which the animals behave. For example, domestic ruminants display behaviors such as growling and head-biting. This often occurs when the animals are establishing a dominance relationship and are not necessarily sexually motivated. Careful analysis must be done to interpret what animal motivations are being expressed by those behaviors. [63]
types of sexual behavior
reproductive sexual behavior
sexual intercourse
Copulation is the union of male and female sex organs, a sexual activity conducted specifically to transmit male sperm into the female’s body. [64]
Cuckoldry
Alternative male strategies which allow smaller males to engage can develop in species such as fish where cuckoldry is dominated by large and aggressive males. Cuckoldry is a type of polyandry, and may be secretly accompanied by spawners. A sneak spawner is a male that rushes to join the spawning rush of a spawning pair. [65] A spawning rush occurs when a fish makes a burst of motion, usually at a vertical tilt, releasing gametes at the top, followed by a rapid return to the lake or sea floor or fish aggregation. [66] Secretly males do not participate in courtship. In salmon and trout, for example, jack malesare common. These are small silvery males that migrate upward with the standard, larger, hook-nosed males and spawn secretly in reds to release sperm together with a mating pair. This behavior is an evolutionarily stable strategy for reproduction, as it favors natural selection, just like the “standard” strategy of larger males. [67]
bisexuality
Bisexuality occurs when a given individual in a species has both male and female reproductive organs, or can alternate between having one first and then the other. It is common in invertebrates but rare in vertebrates. This can be compared to gonochorism, where each individual in a species is either male or female, and remains so throughout life. Most fish are gonochorists, but hermaphroditism is known to occur in 14 families of teleost fishes. [68]
Bisexuals are usually hermaphrodite , meaning they can change sex, usually from female to male (Protogyny) . This can happen when a dominant male is removed from a group of females. The eldest female in the harem can change sex in a few days and replace the dominant male. [68] It is found among coral reef fishes such as groupers, parrotfishes and wrasses. As an example, most wrasses are protogynous hermaphrodites within a hermic reproductive system. [69] [70] It is less common for a male to switch to a female (protandry). [4] : 162A common example of a protandrous species are clownfish – if a large, dominant female dies, in many cases, the breeding male gains weight and becomes a female. [71] [72] Bisexuality allows for complex mating systems. Wrasses exhibit three distinct mating systems: polygynous, lake-like, and promiscuous mating systems. [73]
sexual cannibalism
Sexual cannibalism is a behavior in which a female animal kills and eats a male before, during, or after copulation. Sexual cannibalism confers fitness benefits to both men and women. [74] Sexual cannibalism is common in insects, arachnids [75] and amphibians. [75] There is also evidence of sexual cannibalism in gastropods and copepods. [76]
sexual coercion
Sex has been documented in various species in the context of coercion, either explicitly or implicitly. In some herbivorous herd species, or species where males and females differ greatly in size, the male is sexually dominant by force and size. (Animal Sexual Behavior)
Some species of birds have been observed to mate with an apparent predatory attack; These include ducks, and swans. White-fronted female bee eaters are subjected to forced copulation. When females leave their nests, males sometimes take them to the ground and mate with them. Such forced copulation is preferably performed on females who are laying eggs and therefore can lay eggs fertilized by the male.
It is reported that rhinos were sexually abused and killed by young male elephants in South Africa. [81] This interpretation of the elephant’s behavior was disputed by one of the authors of the original study, who stated that “there was nothing sexual about these attacks”.
untouched reproduction
Parthenogenesis is a form of asexual reproduction in which the growth and development of the embryo occurs without fertilization. [83] Technically, parthenogenesis is not a behavior, however, sexual behavior may be involved.
Whip-tailed lizard females have the ability to reproduce through parthenogenesis and such males are rare and sexual reproduction non-standard. Women use “pseudocopulation” to stimulate ovulation [84]their behavior with their hormonal cycles; During low levels of estrogen, these (female) lizards engage in “masculine” sexual roles. Those animals with higher estrogen levels currently assume “female” sex roles. Lizards who perform courtship rituals have higher fertility than those kept in isolation due to an increase in hormones produced by sexual behavior. Therefore, even though populations of asexual whiptail lizards lack males, sexual arousal increases reproductive success. From an evolutionary standpoint these females are passing on their full genetic code to all their offspring, not 50% of the genes that would be passed on in sexual reproduction. (Animal Sexual Behavior)
True parthenogenesis is rare in fish, where females produce female offspring without any input from males. All female species include Texas silverside, Menidia clarkhubsi [85] and a complex of Mexican mollies. [4] : 162
Parthenogenesis has been recorded in 70 vertebrate species [86] including hammerhead sharks, [87] blacktip sharks, [88] amphibians [89] and lizards. [90]
bisexuality
Bisexuality occurs when a species is all-male or all-female. Some fish species are hermaphrodite and can take complex forms. Squalius alburnoides , found in many river basins in Portugal and Spain, appears to be an all-male species. The existence of this species reflects the potential complexity of mating systems in fish. The species originated as a hybrid between two species and is diploid but not hermaphrodite. There can be triploid and tetraploid forms, including all female forms that reproduce primarily through hybridogenesis. [91]
other
- Interbreeding : Hybrid offspring can result from the mating of two organisms of different but closely related parent species, although the resulting offspring is not always fertile. According to Alfred Kinsey, genetic studies on wild animal populations have shown a “large number” of inter-species hybrids. [92]
- Prostitution: There are reports that animals sometimes indulge in prostitution. Within a group of penguins, a small number of pair-boned females took up nesting material (stones) after copulating with non-mate males. “I was looking opportunistically, so I can’t give a precise figure of how common it really is,” the researcher said. [93] It has been reported that “the swap of meat for sex … is part of the social fabric of a group of wild chimps living in the Tai National Park in Cte d’Ivoire.” [94]
- Pavlovian Conditioning: The sexualization of objects or places is recognized in the animal reproductive world. For example, male animals may become sexually aroused by visiting a place where they have previously been allowed to have sex, or by seeing a stimulus previously associated with sexual activity, such as an artificial vagina. [95] Sexual preferences for certain cues can be artificially induced in rats by associating odors or objects with their initial sexual experiences. [96] The primary motivation for this behavior is Pavlovian conditioning, and this association is due to a conditioned response (or association) formed with a specific “reward”. [96]
- Viewing images: A study using four adult male rhesus macaques ( Macaca mulatta ) showed that male rhesus macaques would drop a highly prized object, the rus, to view images of high-status females’ faces or perineums . [97] Encouraging captive pandas to mate is problematic. Showing “panda pornography” to young male pandas is credited with the recent population boom among pandas in captivity in China. One researcher attributed this success to the sound of the recording. [98]
- Copulative lesions and traumatic insemination : Injury to a partner’s genital tract during intercourse occurs in at least 40 taxa, ranging from fruit flies to humans. However, it often goes unnoticed due to its latent nature and internal wounds not visible outside. [99]
non-reproductive sexual behavior
There are a number of behaviors that animals do that appear to be sexually motivated but which may not result in reproduction. This includes:
- Masturbation: Some species, both males and females, masturbate when mates are available and otherwise. [100] [101]
- Oral sex: Many species engage in both autophaletio and oral sex. It has been documented in brown bears, [102] Tibetan macaques, [103] wolves, [104] goats, primates, bats, [105] [106] Cape ground squirrels [107] and sheep. In the greater lesser nose fruit bat, mating by males is dorsoventral and females lick the shaft or base of the male’s penis, but not the glans which has already entered the vagina. While females do this, the penis is not withdrawn and research has shown a positive correlation between the duration of licking the penis and the duration of copulation. Genital grooming has also been observed after copulation. [108]
- Homosexuality: Same-sex sexual behavior occurs in many species, especially in social species, especially in marine birds and mammals, monkeys and great apes. As of 1999 , there were reports of homosexual behavior in at least 471 wild species in the scientific literature. [109] Organizers Against Nature? The exhibit states that “homosexuality has been observed in 1,500 species, and it is well documented in 500 of them.”
- Genital-Genital Rubbing: This is the sexual act in which an animal rubs its genitals against the genitals of another animal. It has been called “the most distinctive sexual pattern of the bonobo, unspecified in any other primate”. [112] [113]
- Inter-species Mating: Some animals opportunistically mate with individuals of other species. [114]
- Sexes involving juveniles Male: Stoats ( Mustela erminea ) will occasionally mate with infant females of their species. [115] This is a natural part of their reproductive biology—their gestation period is delayed, so these females give birth the following year when they are fully developed. Juvenile male chimpanzees have been recorded growing and copulating with immature chimpanzees. Infants in bonobo societies often engage in sexual behavior. [116]
- Necrophilia: This describes when an animal has sex with a dead animal. It has been observed in mammals, birds, reptiles and frogs. [117]
- Bisexuality: It is described when an animal shows sexual behavior towards both male and female.
- Extended female sexuality: This is when females have intercourse with males outside their gestation period. [118] [22]
sea horse
The seahorse, once thought to be a monogamous species with pairs for life, was described in a 2007 study as “asexual, flighty, and more than a little homosexual”. [119] 15 Aquaria scientists studied 90 seahorses from three species. Of the 3,168 sexual encounters, 37% were homosexual acts. Flirting was common (up to 25 potential mates in a day of both sexes); Only one species (the British spiny seahorse) contained loyal representatives, and for these 5 out of 17 were loyal, 12 were not. The hermaphrodite behavior was widespread and was considered “both a great surprise and a shock”, with large belly seahorses of both sexes not showing mate preference. 1,986 contacts were male-female, 836 female-female and 346 male-female. [119]
bonobo
In addition to bonobos, males and females engage in sexual behavior, with females being particularly noted for engaging in sexual behavior with each other, and sexual activity with the same and opposite sex being non-reproductive As being sexually active, at up to 75% do not necessarily correlate with their ovulation cycles. [112] Sexual activity occurs between almost all ages and sexes of bonobo societies. [120] [121] Primatologist Frans de Waal believes that bonobos use sexual activity to resolve conflict between individuals. [28] [122] Immature bonobos, in contrast, make genital contact when relaxed. [121]
african langur
Same-sex sexual behavior occurs in both male and female macaques. [123] It is believed that this is done for pleasure as an erect male mounts and thrusts upon another male. [123] [124] Sexual receptivity can also be indicated by red faces and screams. [123] Mutual ejaculation has also been observed following a combination of anal intercourse and masturbation, although this may be rare. [124] Compared to socio-sexual behaviors such as displays of dominance, homosexual mounts are longer, occur in series, and usually involve pelvic thrusting. [123]
Women are also believed to participate for pleasure because vulvar, perineal and anal stimulation is part of these interactions. The excitement can come from their own tail, twitching, thrusting, or a combination of these. [125]
dolphin
Male bottlenose dolphins have been observed working in pairs to follow or restrict the movement of one female at a time, waiting for her to become sexually receptive. The same couple has also been seen engaging in intense sexual play with each other. Janet Mann, professor of biology and psychology at Georgetown University, argues that [126] same-sex behavior between male dolphin calves is about bond formation and benefits the species in an evolutionarily fashioned way. They cite studies that have shown that dolphins are bisexual later in life and that homosexual male bonds serve to protect as well as to locate females with which to breed. In 1991, an Englishman was prosecuted for allegedly having sex with a dolphin. [127]The man was found not guilty when trial revealed that dolphin bathers were known to tow through the water by bending it around their penis. [127]
hyena
The female spotted hyena has a unique urogenital system, similar to the male’s penis, which is called a pseudo-penis. Dominance relationships with strong sexual elements are regularly observed between related females. They are notable for using visible sexual arousal as a sign of submission, but do not dominate males as well as females (females tend to have a larger erectile clitoris). [128] It is speculated that to facilitate this, their sympathetic and parasympathetic nervous systems may be partially reversed in relation to their reproductive organs. (Animal Sexual Behavior)
sexual intercourse
spine
mammals
Mammals mate through vaginal sex. To achieve this, the male usually swings the female from behind. [130] The female may exhibit lordosis in which she turns her back abdominally to facilitate penetration of the penis. In land mammals, apart from humans, only bonobos mate in a face-to-face situation, [131] [ better source needed ] as reflected by the anatomy of females, [112] although ventro-ventral copulation has also been observed. in Rhabdomys. [132] Some marine mammals copulate in the belly-to-belly position. [133] [134] Some camels mate while lying down. [135]Ejaculation in most mammals is followed by several injections, [136] but in most primates, copulation consists of a brief introduction. [137] In most ruminant species, there is only one pelvic thrust during copulation. [138] [ 139] In most deer species, a copulatory leap also occurs.
During mating, a “copulative tie” occurs in mammals such as fossas, [142] canids [143] and Japanese martens. [144] Some primate species also have a “copulatory lock”, such as Galago senegalensis. [145]
Copulative behavior of many mammalian species is influenced by sperm competition. [146]
Some women have concealed fertility, making it difficult for men to assess whether a woman is fertile. It is costly because a lot of energy is expended in ejaculation. [22]
invertebrates
Invertebrates are often bisexual. Some hermaphrodite land snails begin mating with an elaborate tactile courtship ritual. The two snails circle around each other for six hours, touching with their tentacles, and touching the area of the lips and genital orifice, which shows some early signs of sex divergence. As the snails approach mating, hydraulic pressure builds up in the blood sinus around the organ housing a pointed dart. The dart is made of calcium carbonate or chitin, and is called a love dart. Each snail maneuvers its genital opening closer to the other snail’s body to best position it. Then, when one snail’s body touches another snail’s genitalia, it triggers the firing of the love dart. [147]After the snails have fired their darts, they copulate and exchange sperm as a separate part of the mating progression. Love darts are covered with a mucus that contains a hormone-like substance that facilitates the survival of the sperm. [148] [149]
Penis fencing is a mating behavior performed by some species of flatworms, such as Pseudobiceros bedfordii . The species that engage in exercise are hermaphrodites, having both eggs and sperm-producing testes. [150] Species “fence” with double-headed dagger-like penises that are pointed and white in colour. One organism conceives another. Sperm are absorbed through pores in the skin, which leads to fertilization.
Corals can be both gonochoristic (sexual) and hermaphrodite, each of which can reproduce sexually and asexually. Breeding also allows corals to settle in new areas. Corals mainly reproduce sexually. 25% of hermaphroditic corals (stony corals) form single sex (gonochoristic) colonies, while the rest are hermaphroditic. [151] About 75% of all hermatypic corals “spawn” by releasing gametes—eggs and sperm—into the water to disperse the offspring. During fertilization the gametes fuse to form a microscopic larva called a planula, usually pink and oval in shape. [152]Synchronous spawning is very typical on coral reefs and often, even when multiple species are present, all corals spawn in a single night. This synchronization is necessary so that the male and female gametes can mate. Corals must rely on environmental cues that vary from species to species in order to determine the proper time to release gametes into the water. Signs include lunar changes, the time of sunset, and possibly chemical signals. [151] Synchronous spawning can form hybrids and is probably involved in coral species. [153]
Butterflies spend most of their time looking for mates. When the male sees a mate, he will fly closer and release pheromones. He then performs a special courtship dance to attract the female. If a woman appreciates dance she can join it. Then they attach their bodies end to end on their abdomens. Here, the male sends the sperm to the female’s egg-laying tube, which will soon be fertilized by the sperm. [154]
Many animals produce mucus plugs after mating to seal the female’s orifice. Normally such plugs are secreted by the male, in order to block the subsequent partners. In spiders the female can assist in this process. [155] Spider sex is unusual in that males transfer their sperm to females on small organs called pedipalps. They use these to pick up their sperm from their genitals and inject them into the female’s sexual opening instead of having sex directly. [155]On 14 occasions a sexual plug was formed, with the female creating it without the help of the male. On ten of these occasions, it appeared that the male’s pedipalps were trapped when transferring sperm (which is rarely the case in other species of spider), and they had great difficulty freeing themselves. In two of those ten cases, it was eaten. [155]
In the orb-weaving spider species Zygiella x-notata , individuals engage in a variety of sexual behaviors, including male selection, mate-guarding, and vibrational cues in courtship. [156] [157]
Genetic evidence of interspecific sexual activity in humans
Research into human evolution confirms that, in some cases, inter-species sexual activity may be responsible for the development of new species. Analysis of animal genes has provided evidence that, even when humans diverged from other apes, interbreeding regularly occurred to replace some of the genes in the new gene pool. [158] The researchers found that the X chromosomes of humans and chimpanzees must have separated from the other chromosomes approximately 1.2 million years later. One possible explanation is that modern humans emerged from a hybrid of human and chimpanzee populations. [159] A 2012 study questioned this explanation and concluded that “there is no strong reason to include complicating factors in interpreting autosomal data”.
avoidance of inbreeding
When close relatives mate, the offspring may exhibit the deleterious effects of inbreeding depression. Inbreeding depression is mainly due to homozygous expression of recessive deleterious alleles. [161] Over time, inbreeding depression can lead to the development of inbreeding avoidance behavior. Several examples of animal behavior that reduce mating of close relatives and inbreeding depression are described further.
Reproductively active female naked mole-rats mate with unfamiliar males (usually non-kin), while reproductively inactive females do not discriminate. [162] The preference of reproductively active females for unfamiliar males has been interpreted as an adaptation to avoid inbreeding.
When rats breed with close relatives in their natural habitat, there is a significant detrimental effect on the survival of the offspring. [163] In the house mouse, the major urinary protein (MUP) gene cluster provides a highly polymorphic odorant signal of genetic identity that appears to be based on kin recognition and inbreeding avoidance. Thus less mating occurs between mice sharing the MUP haplotype than would be expected when random mating occurs. [164]
Meerkat females seem to be able to distinguish the scent of their kin from that of their non-kin. [165] Kin identification is a useful ability that facilitates both cooperation between relatives and the avoidance of inbreeding. When mating occurs between meerkat relatives, it often results in intrauterine depression. Inbreeding depression was evident for a variety of traits: pup mass upon emergence from the natal burrow, hind-leg length, growth to independence, and juvenile survival. (Animal Sexual Behavior)
The gray-sided vole ( Myodes rufocanus ) exhibits male-biased proliferation as a means of avoiding incestuous mating. [167] In matings that involve inbreeding, the number of juveniles weaned in litters is significantly lower than in non-inbred litters indicating inbreeding depression.
In natural populations of the bird Paras major (Great Tit), inbreeding is avoided by dispersal of individuals from their birthplace, reducing the likelihood of mating with a close relative.
Toads, like many amphibians, show loyalty to the breeding site. Those who return to birth ponds to breed will encounter siblings as potential mates. Although incest is possible, Bufo americanus siblings rarely meet. These toads probably recognize close relatives as mates and actively avoid them. Ad vocalizations by males serve as signals by which females recognize their relatives.
