Tend and befriend

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Tend-and-befriend is a behavior exhibited by some animals, including humans, in response to threat. It refers to protection of offspring (tending) and seeking out the social group for mutual defense (befriending). Tend-and-befriend was theorized as having evolved as the typical female response to stress, just as the primary male response was fight-or-flight. The tend-and-befriend theoretical model was originally developed by Dr. Shelley E. Taylor and her research team at the University of California, Los Angeles and first described in a Psychological Review article published in the year 2000.[1]

Versus fight-or-flight[edit]

The fight-or-flight response has been the dominant model of human (and nonhuman animal) responses to stress. The fight-or-flight response is characterized by either confronting a stressor (fight) or fleeing from it (flight). Although both men and women show the biological fight-or-flight pattern of arousal (e.g., elevated heart rate and blood pressure), men's behavior under stress is better characterized by fight (aggression) or flight (e.g., social withdrawal, substance abuse) than is women's behavior.[2] Among humans and other primates, another tendency is to affiliate, that is, to come together in groups in threatening times.[3] Tend-and-befriend refers to the behavioral response of managing stress by caring for offspring and seeking social support.[1][4] Human females are more likely than males to tend to and seek support from others in times of stress.[5]

Females and fight-or-flight[edit]

Due to higher parental investment in most female mammals, females from these species face the challenge of responding to stressors while protecting offspring.[1] Attacking or fleeing from a predator or threat may interfere with females' ability to protect their offspring. Therefore, these challenges faced by females over evolutionary history may have led to the evolution of a tend-and-befriend stress response and mechanisms to inhibit fight-or-flight. Taylor and colleagues suggest that neuroendocrine systems are the mechanisms underlying these adaptive responses to threat.[1]

Human males show higher levels of the physical fight response than females.[6] In contrast to males, females have lower levels of circulating androgens such as testosterone, which are associated with aggression.[7] Following exposure to acute stress, men showed an increase in testosterone, and this increase was associated with hostility.[8] Sympathetic arousal appears to be linked to hostility in men but not in women.[8]

Throughout most of human history, women spent most of their fertile years either pregnant, breastfeeding, or caring for young children. Female stress responses may have evolved to protect both the female and her offspring.[1] When women are pregnant, nursing, or providing childcare, fleeing a stressor may compromise the health and safety of offspring. Oxytocin, a posterior pituitary hormone released in response to stress, may inhibit the flight response.[1] Oxytocin exogenously administered to rats reduced fear, decreased sympathetic arousal, and increased relaxation and sedation.[9] These oxytocin-induced effects were stronger for females. Furthermore, oxytocin and estrogen are both associated with reduced anxiety in humans.[1]

Biological bases[edit]

According to the Polyvagal Theory developed by Dr. Stephen Porges, the "Social Nervous System" is an affiliative neurocircuitry that prompts affiliation, particularly in response to stress.[10] This system regulates social approach behavior. A biological basis for this regulation appears to be oxytocin.[11]

Oxytocin has been tied to a broad array of social relationships and activities, including peer bonding, sexual activity, and affiliative preferences.[11] Oxytocin is released in humans in response to a broad array of stressors, especially those that may trigger affiliative needs. Oxytocin promotes affiliative behavior, including maternal tending and social contact with peers.[12] Thus, affiliation under stress serves tending needs, including protective responses towards offspring. Affiliation may also take the form of befriending, namely seeking social contact for one's own protection, the protection of offspring, and the protection of the social group. These social responses to threat reduce biological stress responses, including lowering heart rate, blood pressure, and hypothalamic pituitary adrenal axis (HPA) stress activity, such as cortisol responses.[13]

Women are more likely to respond to stress through tending and befriending than men. Paralleling this behavioral sex difference, estrogen enhances the effects of oxytocin, whereas androgens inhibit oxytocin release.[14]

Tending under stress[edit]

Female stress responses that increased offspring survival would have led to higher fitness and thus were more likely to be passed on through natural selection.[1] In the presence of threats, protecting and calming offspring while blending into the environment may have increased chances of survival for mother and child. When faced with stress, females often respond by tending to offspring, which in turn reduces stress levels. Studies conducted by Repetti (1989) show that women respond to highly stressful workdays by providing more nurturing behaviors towards their children.[15] In contrast, fathers who experienced stressful workdays were more likely to withdraw from their families or were more interpersonally conflictual that evening at home. Furthermore, physical contact between mothers and their offspring following a threatening event decreased HPA activity and sympathetic nervous system arousal.[16] Oxytocin, released in response to stressors, may be the mechanism underlying the female caregiving response. Studies of ewes show that administration of oxytocin promoted maternal behavior.[17] Breastfeeding in humans, which is associated with maternal oxytocin release, is physiologically calming to both mothers and infants.[1]

Cooperative breeding[edit]

Tend-and-befriend is a critical, adaptive strategy that would have enhanced reproductive success among female cooperative breeders. Cooperative breeders are group-living animals where infant and juvenile care from non-mother helpers are essential to offspring survival.[18] Cooperative breeders include wolves, elephants, many nonhuman primates, and humans. Among all primates and most mammals, endocrinological and neural processes lead females to nurture infants, including unrelated infants, after being exposed long enough to infant signals.[19] Non-mother female wolves and wild dogs sometimes begin lactating to nurse the alpha female's pups.

Humans are born helpless and altricial, mature slowly, and depend on parental investment well into their young adult lives, and often even later.[19] Humans have spent most of human evolution as hunter-gatherer foragers. Among foraging societies without modern birth control methods, women have high parity, tending to give birth about every four years during their reproductive lifespan.[19] When mothers give birth, they often have multiple dependent children in their care, who rely on adults for food and shelter for eighteen or more years. Such a reproductive strategy would not have been able to evolve if women did not have help from others. Allomothers (helpers who are not a child's mother) protect, provision, carry, and care for children.[19] Allomothers are usually a child's aunts, uncles, fathers, grandmothers, siblings, and other women in the community. Even in modern Western societies, parents often rely on family members, friends, and babysitters to help care for children. Burkart, Hrdy, and Van Schaik (2009) argue that cooperative breeding in humans may have led to the evolution of psychological adaptations for greater posociality, enhanced social cognition, and cognitive abilities for cooperative purposes, including willingness to share mental states and shared intentionality.[18] These cognitive, prosocial processes brought on by cooperative breeding may have led to the emergence of culture and language.

Befriending under stress[edit]

Group living provides numerous benefits, including protection from predators and cooperation to achieve shared goals and access to resources. Women create, maintain, and use social networks—especially friendships with other women—to manage stressful conditions.[1] During threatening situations, group members can be a source of support and protection for women and their children. Research shows that women are more likely to seek the company of others in times of stress, compared to men.[20] Women and adolescent girls report more sources of social support and are more likely to turn to same-sex peers for support than men or boys are. Cross-culturally, women and girls tend to provide more frequent and effective support than men do, and they are more likely to seek help and support from other female friends and family members.[21] Women tend to affiliate with other women under stressful situations. However, when women were given a choice to either wait alone or to affiliate with an unfamiliar man before a stressful laboratory challenge, they chose to wait alone.[1] Female-female social networks can provide assistance for childcare, exchange of resources, and protection from predators, other threats, and other group members. Smuts (1992) and Taylor et al. (2000) argue that female social groups also provide protection from male aggression.[1][22]

Neuroendocrine underpinnings[edit]

Human and animal studies (reviewed in Taylor et al., 2000) suggest that oxytocin is the neuroendocrine mechanism underlying the female "befriend" stress response.[1] Oxytocin administration to rats and prairie voles increased social contact and social grooming behaviors, reduced stress, and lowered aggression. In humans, oxytocin promotes mother-infant attachments, romantic pair bonds, and friendships. Social contact or support during stressful times leads to lowered sympathetic and neuroendocrine stress responses. Although social support downregulates these physiological stress responses in both men and women, women are more likely to seek social contact during stress. Furthermore, support from another female provides enhanced stress-reducing benefits to women.[23]

Benefits of affiliation under stress[edit]

According to Taylor (2000), affiliative behaviors and tending activities reduce biological stress responses in both parents and offspring, thereby reducing stress-related health threats.[24] "Befriending" may lead to substantial mental and physical health benefits in times of stress. Social isolation is associated with significantly enhanced risk of mortality, whereas social support is tied to positive health outcomes, including reduced risk of illness and death.[3]

Women have higher life expectancies from birth in most countries where there is equal access to medical care.[25] In the United States, for example, this difference is almost 6 years. One hypothesis is that men's responses to stress (which include aggression, social withdrawal, and substance abuse) place them at risk for adverse health-related consequences.[26] In contrast, women's responses to stress, which include turning to social sources for support, may be protective to health.

Competition for resources[edit]

Group living and affiliation with multiple unrelated others of the same sex (who do not share genetic interests) also presents the problem of competing for access to limited resources, such as social status, food, and mates. Interpersonal stress is the most common and distressing type of stress for women.[27] Although the befriending stress response may be especially activated for women under conditions of resource scarcity,[1] resource scarcity also entails more intense competition for these resources. In environments with a male-biased sex ratio, where males are a more limited resource, female-to-female competition for mates is intensified, sometimes even resorting to violence.[28] Although male crime rates far exceed those of females, arrests for assault among females follow a similar age distribution as in males, peaking for females in the late teens to mid-twenties. Those are ages in which females are at peak reproductive potential and experience the most mating competition. However, the benefits of affiliation would have outweighed the costs in order for tend-and-befriend to have evolved.

Competition and aggression[edit]

Rates of aggression between human males and females may not differ, but the patterns of aggression between the sexes do differ. Although females in general are less physically aggressive, they tend to engage in as much or even more indirect aggression (e.g. social exclusion, gossip, rumors, denigration).[29] When experimentally primed with a mating motive or status competition motive, men were more willing to become directly aggressive towards another man, whereas women were more likely to indirectly aggress against another woman in an aggression-provoking situation.[30] However, experimentally priming people with a resource competition motive increased direct aggression in both men and women. Consistent with this result, rates of violence and crime are higher among males and females under conditions of resource scarcity.[31] In contrast, resource competition did not increase direct aggression in either men or women when they were asked to imagine that were married and had a young child. The costs of physical injury to a parent would also entail costs to his or her family.

Lower variance in reproductive success and higher costs of physical aggression may explain the lower rates of physical aggression among human females compared to males.[31] Females are in general more likely to produce offspring in their lifetimes than males. Therefore, they have less to gain from fighting and the risk of injury or death would produce greater fitness cost for females. The survival of young children depended more on maternal than paternal care, which underscores the importance of maternal safety, survival, and risk aversion.[31] Infants' primary attachment is to their mother, and maternal death increased the chances of childhood mortality in foraging societies by fivefold, compared to threefold in the cases of paternal death.[31] Therefore, women respond to threats by tending and befriending, and female aggression is often indirect and covert in nature to avoid retaliation and physical injury.

Informational warfare[edit]

Women befriend others not only for protection, but also to form alliances to compete with outgroup members for resources, such as food, mates, and social and cultural resources (e.g. status, social positions, rights and responsibilities). Informational warfare is the strategic competitive tactics taking the form of indirect, verbal aggression directed towards rivals.[32] Gossip is one such tactic, functioning to spread information that would damage the reputation of a competitor. There are several theories regarding gossip, including social bonding and group cohesion. However, consistent with informational warfare theory, the content of gossip is relevant to the context in which competition is occurring. For example, when competing for a work promotion, people were more likely to spread negative work-related information about a competitor to coworkers.[32] Negative gossip also increases with resource scarcity and higher resource value. In addition, people are more likely to spread negative information about potential rivals but more likely to pass on positive information about family members and friends.

As mentioned above, befriending can serve to protect women from threats, including harm from other people. Such threats are not limited to physical harm but also include reputational damage. Women form friendships and alliances in part to compete for limited resources, and also in part to protect themselves from relational and reputational harm. The presence of friends and allies can help deter malicious gossip, due to an alliance's greater ability to retaliate, compared to a single individual's ability. Studies by Hess and Hagen (2009) show that the presence of a competitor's friend reduced people's tendencies to gossip about the competitor.[32] This effect was stronger when the friend was from the same competitive social environment (e.g. same workplace) than when the friend was from a nonrelevant social environment. Friends increase women's perceived capabilities for inflicting reputational harm on a rival as well as perceptions of defensive capabilities against indirect aggression.

See also[edit]

References[edit]

  1. ^ a b c d e f g h i j k l m n Taylor, Shelley E.; Klein, Laura Cousino; Lewis, Brian P.; Gruenewald, Tara L.; Gurung, Regan A. R.; Updegraff, John A. (2000). "Biobehavioral responses to stress in females: Tend-and-befriend, not fight-or-flight". Psychological Review 107 (3): 411–29. doi:10.1037/0033-295X.107.3.411. PMID 10941275. 
  2. ^ Williams, David R. (2003). "The Health of Men: Structured Inequalities and Opportunities". American Journal of Public Health 93 (5): 724–31. doi:10.2105/AJPH.93.5.724. PMC 1447828. PMID 12721133. 
  3. ^ a b Cohen, Sheldon; Wills, Thomas A. (1985). "Stress, social support, and the buffering hypothesis". Psychological Bulletin 98 (2): 310–57. doi:10.1037/0033-2909.98.2.310. PMID 3901065. 
  4. ^ "Renew - Stress on the Brain (popular expositions with references)". Franklin Institute. 2004. Retrieved May 9, 2012. 
  5. ^ Belle, D. "Gender differences in the social moderators of stress". Gender and Stress (New York: The Free Press): 257–277. 
  6. ^ Eagly, A. H.; Steffen, V. J. (1986). "Gender and aggressive behavior: A meta-analytic review of the social psychological literature". Psychological Bulletin 100: 309–330. 
  7. ^ Archer, J. "The influence of testosterone on human aggression". British Journal of Psychology 82: 1–28. 
  8. ^ a b Girdler, S. S.; Jamner, L. D.; Shapiro, D. (1997). "Hostility, testosterone, and vascular reactivity to stress: Effects of sex". International Journal of Behavioral Medicine 4: 242–263. 
  9. ^ Uvnas-Moberg, K. (1997). "Oxytocin linked antistress effects – the relaxation and growth response". Acta Psychologica Scandinavica (Supplementum) 640: 38–42. 
  10. ^ Porges, S. W. (2001). "The Polyvagal Theory: Phylogenetic substrates of a social nervous system". International Journal of Psychophysiology 42: 123–146. 
  11. ^ a b Carter, C.S., Lederhendler, I.I., & Kirkpatrick, B., eds. (1999). The integrative neurobiology of affiliation. Cambridge, Mass.: MIT Press.[page needed]
  12. ^ Insel, Thomas R. (1997). "A Neurobiological Basis of Social Attachment". American Journal of Psychiatry 154 (6): 726–35. PMID 9167498. 
  13. ^ Light, Kathleen C.; Smith, Tara E.; Johns, Josephine M.; Brownley, Kimberly A.; Hofheimer, Julie A.; Amico, Janet A. (2000). "Oxytocin responsivity in mothers of infants: A preliminary study of relationships with blood pressure during laboratory stress and normal ambulatory activity". Health Psychology 19 (6): 560–7. doi:10.1037/0278-6133.19.6.560. PMID 11129359. 
  14. ^ McCarthy, MM (1995). "Estrogen modulation of oxytocin and its relation to behavior". Advances in experimental medicine and biology 395: 235–45. PMID 8713972. 
  15. ^ Repetti, R. L. (1989). "Effects of daily workload on subsequent behavior during marital interactions: The role of social withdrawal and spouse support". ournal of Personality and Social Psychology 57: 651–659. 
  16. ^ Gunnar, M. R.; Gonzales, C. A.; Goodlin, B. L.; Levine, S. (1981). "Behavioral and pituitary-adrenal responses during a prolonged separation period in rhesus monkeys". Psychoneuroimmunology 6: 65–75. 
  17. ^ Kendrick, K. M.; Keverne, E. B.; Baldwin, B. A. (1987). "Intracerebroventricular oxytocin stimulates maternal behaviour in the sheep". Neuroendocrinology 46: 56–61. 
  18. ^ a b Burkart, J. M.; Hrdy, S. B.; Van Schaik, C. P. (September 2009). "Cooperative breeding and human cognitive evolution". Evolutionary Anthropology: Issues, News, and Reviews 18 (5): 175–186. doi:10.1002/evan.20222. 
  19. ^ a b c d Hrdy, S. B. "Mothers and Others". Natural History Magazine. 
  20. ^ Tamres, Lisa K.; Janicki, Denise; Helgeson, Vicki S. (2002). "Sex Differences in Coping Behavior: A Meta-Analytic Review and an Examination of Relative Coping". Personality and Social Psychology Review 6: 2. doi:10.1207/S15327957PSPR0601_1. 
  21. ^ Whiting, B.; Whiting, J. (1975). Children of six cultures. Cambridge, MA: Harvard University Press. 
  22. ^ Smuts, B. (1992). "Male aggression against women: An evolutionary perspective". Human Nature 3: 1–44. 
  23. ^ Gerin, W.; Milner, D.; Chawla, S.; et al. "Social support as a moderator of cardiovascular reactivity: A test of the direct effects and buffering hypothesis". Psychosomatic Medicine 57: 16–22. 
  24. ^ Taylor, S.E. (2002). The tending instinct: How nurturing is essential to who we are and how we live. New York: Holt.[page needed]
  25. ^ "WHO Life expectancy data by country". WHO. 2012. Retrieved 1 June 2013. 
  26. ^ Verbrugge, Lois M. (1985). "Gender and Health: An Update on Hypotheses and Evidence". Journal of Health and Social Behavior 26 (3): 156–82. JSTOR 2136750. PMID 3905939. 
  27. ^ Davis, M. C.; Matthews, K. A.; Twamley, E. W. (1999). "Is life more difficult on Mars or Venus? A meta-analytic review of sex differences in major and minor life events". Annals of Behavioral Medicine 21: 83–97. 
  28. ^ Campbell, A. (1995). "A few good men: Evolutionary psychology and female adolescent aggression". Ethology and Sociobiology 16: 99–123. 
  29. ^ Bjorkqvist, K.; Niemela, P., eds. (1992). Of mice and women: Aspects of female aggression. San Diego, CA: Academic Press. 
  30. ^ Griskevicius, Vladas; et al. (2009). "Aggress to Impress: Hostility as an Evolved Context-Dependent Strategy". Journal of Personality and Social Psychology 96 (5): 980-994. doi:10.1037/a0013907. 
  31. ^ a b c d Campbell, A. (1999). "Staying alive: Evolution, culture, and women’s intrasexual aggression". Behavioral and Brain Sciences 22: 203–252. 
  32. ^ a b c Hess, Nicole; Hagen, Edward (2002). "Informational warfare: Coalitional gossiping as a strategy for within-group aggression". Cogprints. 

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