Non Human Primate Reproductive Strategies

Female gorillas leave the group when they are mature enough to start breeding. Females often do not get attached to one another, for competition of grooming and staying

Reproductive monogamy is defined as an exclusive sexual relationship between a female and a male based on their sexual interactions. Social Monogamy refers to male and female’s social living arrangement without sexual interactions. It refers to the living patterns, raising offsprings, and obtaining food. Monogamy is common in birds, but also occurs in invertebrates. Why would a male mammal choose to mate with one female when he can mate with more than one? Why would the male stay around instead of finding another female to live with? Many researchers have attempted to answer this question of why some mammals prefer monogamy over polygamy. Vole rats, one of the species that perform monogamous mating, demonstrate pair boding. Male and female pairs of vole rats have been observed together over several months, and the males stay with females even when the female is not reproductively active. A typical vole family in the wild is almost always consisted of one male, one female, and their offspring. In addition, unlike other species in which females are the only ones taking care of the offspring, vole rats share parental roles and even build nests together. Because they show these monogamous behaviors, they have served as a good species/model to learn about monogamy for neuroscientists. In this paper, monogamy, specifically in vole rats, will be explained along with its proximate and ultimate causes of this adaptation.

Mate choice is a product of mate preferences form in the environment of evolutionary adaptiveness (EEA). Sexual selection suggests that females prefer males who they can gain benefits from such as gifts. This is shown in male birds who make nests for females in order to mate with them and also in insects who give nuptial gifts.

In his article, The Strategies of Finding a Mate, David M. Buss discusses the act of finding a mate and the characteristics that people are drawn to in a mate. He begins the article with a brief look at the history of mating and the theories that have previously been proposed. In particular he addressed Charles Darwin’s theory of sexual evolution and belief in preferential mate choice. Buss proposes that there are three components to human mating. He states that “human mating is inherently strategic… mating strategies are context-dependent… [and that] men and women have faced different mating problems over the course of human evolution and, as a consequence, have evolved different strategies” (Buss, 1994, p. 241). He uses this theory to propose nine different hypotheses to prove that despite humans being varied and different from each other, all humans look for similar characteristics when trying to find a mate (Buss, 1994).

“Pair Living Primates have several unique characteristics that set them apart from other nonhuman primates. Monogamous Primates are two primates of different sexes that mate exclusively with one and other. The unique qualities of these animals are a result of the ecological constraints that these primates face. Because of the exclusive and solitary relationship that is monogamy there is a lack of specialized defensive roles by the adult male, which is also extensively involved in paternal care. Monogamous primates are highly territorial and very closely associated, Morphologically, there is a lack of sexual dimorphism amongst pair living primates, this is due to the exclusively and predictable genetic outcome of these animals mating with only

Orangutans (Figure 3) are our first cousins since they share 97 percent of our genetic material. Contrary to other apes, orangutans are semi solitary which is unique in its social organization (3). Adult males which are the most solitary, and they associate with only their current, former, and potential consorts. For the semi-solitary orangutans, the only playmate is its mother. Even female adults are more social than male ones, rarely they groom, touch, hold hands, chase, or fight. On rare occasions, female adults may groom; however, it lasts only few seconds. Sometimes, female adults meet and travel with one another to express the close relationship. The long call by a male orangutan expresses an alert to others about his presence. Usually, other orangutans only react if the call is close by or aggressive towards them. Male orangutan can use vocalization to express that he is angry and frustrated, and that call signals a threat to another male (3). Female orangutans also produce vocalization when they get upset by the presence of another male.

When discussing female long-term mating strategies, it has been identified that there are certain preferences in which a female desire from a mate (Buss, 2008). Preferences include, a preference for economic resources, a preference for industriousness and ambition, a preference for a good physical appearance and health, and also a preference for dependability and stability. Females prefer someone they can invest in and someone that is willing to invest in them also. And they also desire a mate that can physically protect them and their children and that is both healthy and displays compatibility. There are preconditions as too why these preferences have evolved, such as the idea that resources have been made more defensible and accruable and are more controlled by men, and the idea that men would have to be different between each other in their willingness to somewhat invest their resources in both women and their children. Belsky et al (1991) discovered that some men would rather invest in many women rather than one women and their children as this would mean them

Primate diversity can be strongly seen amongst the Bonobos and Chimpanzees; however, each primate species shares similar social traits that are common among the human species. In the various short videos on Bonobos and Chimps indicated that Chimps are violent creatures where males must assert social dominance by abusing their female counterpart. If a group of chimps were to encounter another group of chimps then there would be war amongst the two group. On the other hand, bonobos are the complete opposites of the chimp cousins. Bonobos are female dominant primate species and disputes are handled with intercourse. Intercourse for the bonobos species is also used to solidify relationships amongst both males and females. When two different groups of bonobos meet one another there are friendly interaction and the two groups would

In site one, where the Parahomo fracticranius was discovered, it can be assumed that the habitat for the species was an open grassland due to the fact that other fossils of animals that lived in the area were grazers. Since there were 14 remains of both male and female sexes, it can be assumed that the P. fracticranius lived in a large multi-male, multi-female system. Based on the lectures from class, it is known that for most cases, multi-male, multi-female environments result in polypoly mating (Atkisson Lecture: Primate mating systems and primate evo). Therefore, it can be assumed that the P. fracticranius not only engaged in polypoly mating, but they also had some sexual dimorphism and large testes. The evidence that supports the sexual dimorphism claim can be seen when the body size of the female and male are compared since the male’s body size is 41 kg larger than the female’s.

I decided to look at the sexual behavior of bonobos because they are known for their frequent sexual behavior. Though they are not one of the types of great apes mentioned in the book, a bonobo is nonetheless a great ape that belongs in the same genus as the common chimpanzee. Furuichi et al. observed bonobos in their naturalistic habitat in Wamba, Democratic Republic

In 1981 Owen Lovejoy suggested that behavioral mechanisms were a factor in the switch to bipedalism. This behavioral mechanism helped hominids in reproductive processes. Having the hands free to carry food and other things to the mate and offspring is seen to be a strong selection factor for choosing a mate. Having a such factor helps with reproductive success in a monogamous mating structure similar to what humans have today (Jacobs, 90). When

Thus, her breeding span is limited (79). In contrast, for males, it is minimal. He simply must produce sperm cells and go through with an act of copulation, in effect, his reproductive capability is limited by the number of females he mates with (Contrary to popular belief, humans are not a monogamous species but a largely monogamous and partly polgynous species) (Gray 79& 83). In addition, males must play the aggressor role in relationships and are more attracted to physical stimuli (Kanin pg. 71). These all require that males recognize love much more quicker then females (Kanin pg. 71).

Males and females differ considerably in how much they each invest in order to make offspring and a result of this, they approach mating with different methods. Researchers and scientists learn and examine these varying mating systems to explain how males and females pair up. A mating system explains the techniques males and females use to pair up when selecting a mate. It is important to begin by reviewing and understanding the reproductive strategies among primates. The major types of mating systems found in primates are monogamy and polygamy. Monogamy is a practice of mating in which one male pairs with one female. Polygamy also known as bisexual, is a pattern of mating in which a male mates with more than one female and a female mates with more than one male (Wong , 2010). Polygamy is then clarified into polygyny and polyandry. Polygyny is when one male mates with multiple females. Polyandry is when one female mates with multiple males. Recognizing the diversity of mating systems will help in understanding the interactive relationship of sexual size dimorphism and behavior in primates.

I can live in “both swamp and terra firma lowland forests throughout the Western Equatorial Africa.” (IUCN, 2016). We usually live in groups, mostly from 5 to 15 members, with a dominant male who serves as our alpha and protector. The dominant male gorilla will be chosen if he is the strongest and oldest silverback within the group (Seaworld Parks and Entertainment, 2016), and because of the privileges of being an alpha, which is having the opportunity to mate with the females in the group, to become the dominant one who usually makes the decision when to eat or move out to another place, he sometimes have to compete or to show off with the other silverbacks or male gorillas in order to maintain his position and

The first few chapters discuss in depth both the general rules for mate selection and the differences in mate selection and varying preferences for male and female genders. As explained in the intro the author theorizes that the current behavior of humans in relation to mating behavior can be linked to our evolutionary past. He references Charles Darwin 's theory of evolution and his idea of natural selection, which is the the process through which organisms adapt to their environment and in doing so tend to