User:Choco Xiu/sandbox

Polygyny

 * competitive infanticide: in lions, hippopotamuses, and some monkeys, the new male will kill the offspring of the previous alpha male to cause their mothers to become receptive to his sexual advances since they are no longer nursing. To prevent this, many female primates exhibit ovulation cues among all males, and show situation-dependent receptivity.

Polygynandry
In bonobos, the amount of promiscuity is particularly striking because bonobos use sex to alleviate social conflict as well as to reproduce.

Types of Sexual Behaviour
Non-reproductive sex behaviour


 * Extended female sexuality: This is when females mate with males outside of their conceptive period.[117]

Bonobo
The bonobo is a fully bisexual species. Both males and females engage in sexual behaviour with the same and the opposite sex, with females being particularly noted for engaging in sexual behaviour with each other and up to 75% of sexual activity being non-reproductive, as being sexually active does not necessarily correlate with their ovulation cycles. Sexual activity occurs between almost all ages and sexes of bonobo societies.[120] Primatologist Frans de Waal believes that bonobos use sexual activity to resolve conflict between individuals.[119] Immature bonobos, contrariwise, perform genital contact when relaxed.

Macaques
Similar same-sex sexual behaviours occur in both male and female macaques. It is thought to be done for pleasure as an erect male mounts and thrusts upon or into another male. Sexual receptivity can also be indicated by red faces and shrieking. Mutual ejaculation after a combination of anal intercourse and masturbation has also been witnessed, although it may be rare. In comparison to socio-sexual behaviours such as dominance displays, homosexual mounts last longer, happen in series, and usually involves pelvic thrusting.

Females are also thought to participate for pleasure as VPA (vulvar, perineal, and anal) stimulation is part of these interactions. The stimulation can come from their own tails, mounting their partner, thrusting, contact between both VPAs, or a combination of these.

Parental investment and reproductive success
Female and male sexual behaviour differ in many species. Often, males are more active in initiating mating, and bear the more conspicuous sexual ornamentation like antlers and colourful plumage. This is a result of anisogamy, where sperm are smaller and much less costly (energetically) to produce than eggs. This difference in physiological cost means that males are more limited by the number of mates they can secure, while females are limited by the quality of genes of her mates, a phenomenon known as Bateman's principle. Many females also have extra reproductive burdens in that parental care often falls mainly, or exclusively, on them. Thus, females are more limited in their potential reproductive success. In species where males take on more of the reproductive costs, such as sea horses and jacanas, the role is reversed, and the females are larger, more aggressive and more brightly coloured than the males.

In hermaphroditic animals, the costs of parental care can be evenly distributed between the sexes, e.g. earthworms. In some species of planarians, sexual behaviour takes the form of penis fencing. In this form of copulation, the individual that first penetrates the other with the penis, forces the other to be female, thus carrying the majority of the cost of reproduction. Post mating, banana slugs will some times gnaw off their partners penis as an act of sperm competition called apophallation. This is costly as they must heal, and spend more energy courting conspecifics that can act as male and female. A hypothesis suggests these slugs may be able to compensate the loss of the male function by directing energy that would have been put towards it to the female function. In the grey slug, the sharing of cost leads to a spectacular display, where the mates suspend themselves high above the ground from a slime thread, ensuring none of them can refrain from taking on the cost of egg-bearer.

Mammals
Mammals mate by vaginal copulation. To achieve this, the male usually mounts the female from behind.[125] The female may exhibit lordosis in which she arches her back ventrally to facilitate entry of the penis. Amongst the land mammals, other than humans, only bonobos mate in a face-to-face position[126][better source needed] as the females' anatomy seems to reflect, although ventro-ventral copulation has also been observed in Rhabdomys.[127] Some sea mammals copulate in a belly-to-belly position.[128][129] Some camelids mate in a lying-down position.[130] In most mammals ejaculation occurs after multiple intromissions,[131] but in most primates, copulation consists of one brief intromission.[132]In most ruminant species, a single pelvic thrust occurs during copulation.[133][134] In most deer species, a copulatory jump also occurs.[135][136]

During mating, a "copulatory tie" occurs in mammals such as fossas,[137] canids[138] and Japanese martens.[139] A "copulatory lock" also occurs in some primate species, such as Galago senegalensis.[140]

The copulatory behavior of many mammalian species is affected by sperm competition.[141]

Some females have concealed fertility, making it difficult for males to evaluate if a female is fertile. This is costly as ejaculation expends much energy.

Peer Review
I would suggest elaborating further on your contributions to provide enough material for a final project. Also, when referencing things in text, you only need to use superscripts to connect them to your references, your in-text references are improperly formatted. Also, adding information about the costs and benefits of certain behaviours and why they may be observed would be beneficial.

Content
The mating systems in the introduction and content of 'polygyny', 'polyandry', and 'promiscuity' should be organized under 'polygamy'. Promiscuity is also scattered throughout the article, however, unlike the other mating systems it does not have a sub-section to itself, so some information may be left out. The layout of the article is messy, as it includes topics not previously mentioned (such as 'parental investment and reproductive success', 'seasonality', 'hormones' and motivation, 'koinophilia', 'interpretation bias', 'genetic evidence of interspecies sexual activity' and 'inbreeding avoidance') and loosely follows the order of the introduction. The article could be cleaned up by including relevant topics in the introduction and following the order throughout the article, combining the sub-sections of 'mating behaviour' with 'reproductive sexual behaviour' under 'types of sexual behaviour', including 'parental investment and reproductive success', 'koinophilia' (if needed at all, as there is no other mention in the article of how mates are chosen), 'genetic evidence of interspecies sexual activity', and 'inbreeding avoidance' under 'reproductive sexual behaviour'. Under 'seasonality', 'mammals', the last sentence in the first paragraph can be made grammatically correct by omitting "as do occur" and changing the sentence to: "Sexual behaviour may occur outside estrus, and such acts are not necessarily harmful".

Tone
The article keeps a neutral tone throughout. However, as mentioned previously, 'promiscuity' is not covered as well as the other 'mating systems'. Another topic that is not covered in-depth is 'vertebrates' (which has three small paragraphs), as compared to 'invertebrates' (which has five large paragraphs).

Talk Page
The talk page mentions a section on moles that has been removed, a section on '"stags fighting" as sexual behaviour' which addresses the lack of a reference, three 'external links modified' by a bot, and a suggestion to add some facts from this article's 'sexual coercion' section to the main 'sexual coercion' article. The top of the page also says that WikiProject Animals and WikiProject Sexology and sexuality, both rated C-class, mid-importance, are interested in this article. Some tasks that need to be completed include bringing over information from the French version of the sub-topics, and adding information to 'sexual behaviour of domestic animals', 'copulatory behaviour of mammals', 'sexual behaviour of African mammals', 'mating behaviour of non-human primates', and 'copulatory behaviour of other vertebrates'. Possible sources that can be used are also mentioned.