Table of ContentsWhat causes primate social behavior?GroomingFood sharingOther examples of altruismConclusionWhat causes the social behavior of primates?According to the American biologist Edward Wilson, social behavior in primates is caused by evolution (Larsen, pp. 194). However, even though aggression and altruism have opposite meanings, both elements are present in the primate world. What aspects of evolution have led to the presence of two contradictory elements in primates, including humans, until today? The intention of this article is to investigate the presence of altruism and aggression in human and non-human primates and to understand why this is considered important for evolution. Say no to plagiarism. Get a tailor-made essay on "Why violent video games should not be banned"? Get the original essay In the selfish gene theory, Richard Dawkins (1976) explains that human evolution is due to the selfish nature of our genes . He believes that our evolution is due to the desire of our genes to survive and reproduce. However, time has shown that humans care about more than just themselves and have demonstrated altruistic behavior over time (Slyke, 2010). Altruism is defined as behavior toward a recipient that benefits the recipient at the expense of the actor performing the behavior (de Waal, 2008). Altruism is common among humans, even toward strangers where there is no anticipated benefit to acting altruistically (Fehr & Fischbacher, 2003). Reciprocal altruism involves helping someone who has helped you in the past (Slyke, 2010). Indirect reciprocity is the act of helping someone when there is no direct benefit; however, as a result, your reputation for honest helping increases and thus increases your chances of receiving benefits in the future (Slyke, 2010). Humans can also be motivated to act altruistically purely out of empathy or concern for the recipient (Silk & House). , 2011). On the other hand, their altruistic behavior may be due to selfish reasons in which the actor expects expected benefits (Silk & House, 2011). Competitive altruism was also found to be present in humans in a study in which participants increased their generosity to increase their self-presentation in order to be chosen as a social partner (Barclay & Willer, 2007). Parent selection is also an evolutionary process of altruism. in that humans often help family members more often than strangers (Slyke, 2010). As you can see, altruism can be demonstrated by humans in many ways and for many reasons, from improving their reputation to empathizing with someone and understanding their need for help . How are these altruism mechanisms important for human evolution? According to one study on altruism, altruism toward nonkin was actually considered a sexually selected human trait that people sought in potential partners (Phillips, Barnard, Ferguson, & Reader, 2008). . This supports the idea that altruism is a component of sexual selection that is important for evolution in humans (Philips et al., 2008). Altruism, as a whole, can also contribute to our evolution by ensuring our survival. Many humans perform many altruistic acts every day, such as holding the door open for someone or letting them go ahead of them in a grocery store line. These small acts may not increase ourchances of survival, but greater acts can do so. For example, a person can give money to someone in need. The person can use this money to acquire the food necessary for survival. This act, and others like it, allows one to survive and possibly reproduce, which would contribute to our evolution as a whole. Altruism also increases social bonds and cooperation, which can also be considered an important part of survival (Slyke, 2010). Nonhuman primates are also prone to altruism (Warneken, Hare, Melis, Hanus, & Tomasello, 2007). Throughout my research, I have noticed that humans and non-human primates exhibit altruism for many of the same reasons. However, there are also some differences. In non-human primates, altruism can be expressed through grooming, food sharing, and other diverse situations for multiple reasons. GroomingAllogrooming, or social grooming, is perhaps the most common altruistic behavior among primates (Schino and Aureli, 2010). A possible motivation for primate grooming is kin selection, in which primates groom those with whom they are related (Schino and Aureli, 2008). For example, rhesus and Japanese macaques spend more time grooming their close relatives than their more distant relatives (Silk, 2002). Reciprocal altruism is another explanation for grooming, as is the case in red-fronted lemurs (Eulemur fulvus rufus) (Port, Clough, & Kappeler, 2009). In fact, Schino and Aureli (2010) conducted a study that found that the distribution of grooming in primates was explained more by reciprocity than by kin selection. However, this does not mean that grooming is equally reciprocal. In red-fronted lemurs, female primates that ranked low in their group were those who groomed others the most, relative to the amount of grooming they received (Port et al., 2009). Port et al. (2009) also found that, on average, males reciprocated less to females than they received from females. What other reasons justify the use of grooming in the primate world? In chimpanzees, grooming has been used to gain future help from those they groom (Koyama, Caws, & Aureli, 2006). Additionally, although this does not fit the usual definition of grooming, primates often clean the wounds of their conspecifics, or members of their species, in an attempt to heal the wound (de Waal, 2008). Finally, grooming may be exchanged for tolerance by the excluded, particularly at feeding sites, where food is unlikely to be shared with them (Silk, 2002). How is grooming important for evolution? Just like humans, it is important because it forms stronger social bonds. It also sparks cooperation for future conflicts, helping to ensure the survival of the species (Koyama et al., 2006). Grooming can also be used in exchange for food, which is of course necessary for survival (Frank & Silk, 2009). In addition, cleaning the wounds can ensure the survival of the individual who will then have the capacity to reproduce. The next example of altruism displayed in primates is food sharing. Food Sharing Food sharing is perhaps the second most common form of altruism within the primate community (Silk, Brosnan, Henrich, Lambeth, & Shapiro, 2013). Jaeggi & van Schaik (2011) stated that among non-human primates, chimpanzees are the only species that share food withadults in the wild. However, Silk & House (2011) found that marmosets, capuchins and tamarins give even more food than chimpanzees. During field observations at the Ellen Trout Lufkin Zoo, I witnessed food sharing between two white-faced sakis (Pithecia pithecia). I'm not sure of the underlying cause of this sharing as I don't know the relationship between the two monkeys. The male would go to his food bowl and take two food pellets, then give one to the female. Food sharing patterns among primates have been shown to be due to reciprocity, kin selection, strengthening social bonds, and appeasement of beggars (Silk & House, 2011). Meat sharing is common among chimpanzees after a group hunt (de Waal & Suchak, 2010). Those who actually participated in hunting had easier access to food than those who did not participate (de Waal and Suchak, 2010). Food sharing is in very need of evolution. Food. Food is necessary to survive and survival is necessary to reproduce. Other examples of altruismAlarm calls, which involve a primate emitting a loud call to alert its conspecifics that there is a threat approaching or nearby, are considered an act of altruism because it puts the actor in danger while benefiting others (Silk, 2002). Tree bridging, in which a primate uses its body as a bridge between two trees to help younger ones, is a common altruistic act among orangutans (van Schaik, 2004). During my field observations, I observed a De Brazza mother's monkey moving around her cage with her young offspring clinging to her belly. Acts like these show the strong bond that exists between primates. A study examining altruism in chimpanzees and human infants found that chimpanzees and infants helped strangers without expecting reward (Warneken et al., 2007). Warneken et al. (2007) also found that chimpanzees also helped other chimpanzees who were unrelated and unknown to them. Alarm calls are a motivation for evolution to the extent that they ensure the survival of the greatest number, even if they may sacrifice the life of the caller (Silk, 2002). ). Alarm calls ensure that the group is aware of a threat and can prepare for it (Silk, 2002). Tree bridging can be considered helpful to the survival of young chimpanzees as it ensures that they will reach the next tree safely. It certainly doesn't harm evolution, maybe it's a better way to look at it. Chimpanzees helping other chimpanzees who are not related to them can be seen as contributing to the survival of chimpanzees as a whole instead of just helping their lineage. The fact that humans and non-human primates are willing to help non-kin conspecifics shows how similar we are to other primates. Another similarity we share is aggression. Aggression has been defined by many psychologists as any behavior that one person displays toward another with the intention of harming someone who does not want to be harmed (Baumeister & Bushman, 2014). Aggression in humans has been subdivided into reactive aggression, which is an unplanned emotional response to provocation, and proactive aggression, which is planned, controlled, goal-directed behavior (Nouvion, Cherek, Lane, Tcheremissine and Living, 2007). ).Men have been found to be more aggressive towards people of the same sex, as well as towards people of the opposite sex (Wolfer and Hewstone, 2015).However, women are more likely than men to exhibit relational aggression, such as spreading rumors about someone or excluding them from their group (Baumeister & Bushman, 2014). In humans, most aggression involves familiar people (de Waal, 2000). A major difference between aggression in humans and non-human primates is the ability of humans to commit aggression using modern weapons (Cashdan and Downes, 2012). Aggression in humans ranges from domestic violence, to bar fights, to shoving or even killing someone, with or without a weapon. The reasons for aggression in humans are also complex and extensive. Some of the reasons are infidelity, lying, provocation, jealousy, trying to impress a potential partner, or having an incentive, such as money. How are primates different when it comes to aggression? One of the theories designed to explain aggression in primates is the male mate defense hypothesis, in which male aggression increases in the presence of females in heat (Kitchen & Beehner, 2007). This theory has been supported by evidence found in chimpanzees (Pan troglodyte), Japanese macaques (Macaca fuscata), bonnet macaques (M. radiate), and blue monkeys (Cercopithecus mitus) (cited in Kitchen & Beehner, 2007 ). This was also found to be true for white-faced sakis (Pithecia pithecia), whose primary reason for intergroup aggression appears to be maintaining exclusive access to females (Thompson, Norconk, & Whitten, 2012). In female chacma baboons, females in heat receive the most aggression, showing that females also fight for potential mates (Huchard and Cowlishaw, 2011). Additionally, pregnant chacma baboons have been found to be the most aggressive, likely due to competition for food resources involved in successful gestation and lactation (Huchard and Cowlishaw, 2011). In polygamous species, such as olive baboons (Papio anubis), males are chosen as mates based on their competitive prowess, thus having increased levels of male-male aggression (Sapolsky, 2006). Mountain gorillas also choose mates based on their fighting abilities (Robbins, Gray, Uwingeli, Mburanumwe, Kagoda, & Robbins, 2014). Aggression can take many different forms, including vocalizations, chasing, injury, and sometimes killing of conspecifics (Harris, 2007). Aggression in green monkeys (Chlorocebus aethiops) is manifested by threats, chasing, hitting, lunging, pushing and biting (Chalyan & Meishvili, 2007). In one species of macaques (Macaca mulatta), the intensity of aggression is high with lots of biting. (Thierry, 1985). In green monkeys, males exhibited higher levels of aggression than females due to the competitive nature to achieve high status and access to females (Chalyan & Meishvili, 2007). In marmosets (Callithrix iacchus), aggression increases in families that contain more than five individuals (de Filippis, Chiarotti, & Vitale, 2009). Hanya (2009) studied the occurrence of aggression during feeding time in wild Japanese macaques. He found that the fewer feeding sites, the higher the level of aggression displayed. However, aggression was only exhibited when feeding high-quality foods, such as fruits and seeds, as opposed to low-quality foods, such as leaves and flowers (Hanya, 2009 ). Bwindi mountain gorillas also fight for high-quality food.