Biology:Alpha (ethology)

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Short description: Individual in the community with the highest rank
Male "silverback" gorillas are usually the alpha animal and may receive preferential treatment such as being groomed by other group members

In studies of social animals, the highest ranking individual of a dominance hierarchy is sometimes designated as the alpha. Males, females, or both, can be alphas, depending on the species. Where one male and one female fulfill this role together, they are sometimes referred to as the alpha pair. Other animals in the same social group may exhibit deference or other species-specific subordinate behavior towards the alpha or alphas.

Alpha animals usually gain preferential access to food and other desirable items or activities, though the extent of this varies widely between species. Male or female alphas may gain preferential access to sex or mates; in some species, only alphas or an alpha pair reproduce.

Alphas may achieve their status by superior physical strength and aggression, or through social efforts and building alliances within the group,[1] or more often, simply by breeding and being the parent of all in their pack.[2] The individual with alpha status sometimes changes, often through a fight between the dominant and a subordinate animal. These fights are often to the death, depending on the animal.[3]

Beta and omega

Social animals in a hierarchical community are sometimes assigned ranks in ethology studies.

  • Beta animals are collaborators, often act as second-in-command to the reigning alpha or alphas and will act as new alpha animals if an alpha dies or is otherwise no longer considered an alpha. In some species of birds, males pair up in twos when courting, the beta male aiding the alpha male. It has been found that the social context of the animals has a significant impact on courtship behavior and the overall reproductive success of that animal.[4]
  • Omega has a conflicted meaning ranging from "runt" to "lone wolf". As an antonym it is used to refer to the lowest caste of a hierarchical society. Following the theories that omega animals are subordinate to all others in the community, and are expected by others in the group to remain submissive to everyone. Omega animals may also be used as communal scapegoats or outlets for frustration, or given the lowest priority when distributing food.[5] These same researchers also compared the omega wolf to a "court jester," being first to initiate play, and while submissive, well liked and not outcast. In the pack under study, the omega named Lakota was in fact the largest and strongest of the wolves.[6]

Examples

Primates

Researcher M.W. Foster investigated primates and found that the leaders were more likely to be those who did more for those around them instead of being determined by strength.[7]

Baboons

Alpha male baboons monopolize resources and mating access to females, and they are also more likely to suffer from stress.[8] Lower status males must expend more time and energy for mating opportunities. Alpha males may sometimes allow subordinate males to have access to mating, so the subordinate males can serve as "spare dads" and protect their offspring from other alpha males.[9]

Capuchin monkeys

A study on the association of alpha males and females during the non-breeding season in wild Capuchin monkeys (Cebus apella nigritus) examined whether alpha males are the preferred mate for females and, secondly, whether female-alpha status and relationship to the alpha-male can be explained through the individual characteristics and or social network of the female.[10] The results indicated that alpha male Capuchin are the preferred mate for adult females. However, only the alpha females had strong interactions with the alpha males by virtue of a dominance hierarchy among the females in which only the most dominant and strong females were able to interact with the alpha male.[10]

Chimpanzees

Common chimpanzees use strength, intelligence, and political alliances to establish and maintain alpha position.[11] There have been rare cases where a group has killed the alpha male.[12][13] Common chimpanzees show deference to the alpha of the community by ritualized postures and gestures such as presenting their back, crouching, bowing, or bobbing.[14] [verification needed] Chimpanzees lower in rank than the alpha male will offer their hand while grunting to the alpha male as a sign of submission.[15] Bonobo society on the other hand is governed by alpha females. Males will associate with females for rank acquisition because females dominate the social environment. If a male is to achieve alpha status in a bonobo group, he must be accepted by the alpha female.[16] Female bonobos use homosexual sex to increase social status. High-ranking females rarely interact sexually with other females, but low-ranking females interact sexually with all females.[17]

Gorillas

Gorillas use intimidation to establish and maintain alpha position. A study conducted regarding the reproductive behavior of male mountain gorillas (Gorilla beringei beringei) found further evidence that dominant males are favored to father offspring, even when there is a greater number of males in a notably enlarged group size. The study also concluded that mating access dropped off less steeply with status; alpha, beta, and gamma showing more similar mating success, compared to what had been previously thought.[18]

Mandrills

Adult male mandrills with alpha status display vivid colouration on their skin, while those with beta status are more dull in colour. Both types of males engage in mating, but only the dominant alpha males have the ability to produce offspring. Male mandrills sometimes fight for breeding rights which results in dominance. Though conflicts are rare, they can be deadly. Gaining dominance, that is becoming the alpha male, results in an "increased testicular volume, reddening of sexual skin on the face and genitalia, and heightened secretion of the sternal cutaneous gland".[19] When a male loses dominance or its alpha status, the reverse happens, although the blue ridges remain brightened. There is also a fall in its reproductive success. This effect is gradual and takes place over a few years.[20][21][22] When beta males mate-guard a female, the competition between them allows the alpha males to have a greater chance of producing offspring,[23] since betas outnumber alphas 21 to 1.

Birds

Chiroxiphia

Male chiroxiphia can typically be designated alpha and beta, since there is a clear dominance relationship between them.[24] There is only ever one alpha male, but, depending on species, there may be one or two beta males. Beta males are sometimes sub-adults - easily recognized, as their plumage retain female-like characters. Only the alpha male is ever seen to mate with the female.

Montezuma oropendolas

Webster et al. observed that males defend sexually-receptive females, suggesting that Montezuma oropendolas have a female-defence mating system. While the females nest, the males fight and fend off one another, and the males were ranked depending on the outcome of each fight. The alpha male eventually pushes out all other males until he is the only one left. When the alpha males leave the others come back and defend females until he returns. This type of mating system is similar to that of polygynous mammals, not birds.[25]

Pale chanting goshawks

Normally, females mate with a single male (monogamy), but in "broken veld" vegetation (a prey-rich habitat in the Little Karoo), a female and two males may form a polyandrous trio.[26] In these cases an alpha male and female will be assisted in raising the young by a beta male. The alpha male copulates with the female 31-5 days before laying while the beta male copulates 5-3 days before laying.[27] Subordinate co-breeding males may have reproductive fitness benefits by assisting the alpha female with nest defense and prey provision.[28] Non-breeding individuals from previous broods may remain in their natal territory and form part of the breeding group.[26]

Fish

Cichlid

Aggressive behavior in cichlids is ritualized and consists of multiple displays used to seek confrontation while being involved in evaluation of competitors,[29] coinciding with temporal proximity to mating. Displays of ritualized aggression in cichlids include a remarkably rapid change in coloration, during which a successfully dominant[29] territorial male assumes a more vivid and brighter coloration, while a subordinate or "nonterritorial" male assumes a dull-pale coloration.[30] In addition to color displays, cichlids employ their lateral lines to sense movements of water around their opponents to evaluate the competing male for physical traits/fitness.[31] Male cichlids are very territorial due to the pressure of reproduction, and establish their territory and social status by physically driving out[32] challenging males (novel intruders)[33] through lateral displays (parallel orientation, uncovering gills),[34] biting, or mouth fights (head-on collisions of open mouths, measuring jaw sizes, and biting each other's jaws). The cichlid social dichotomy is composed of a single dominant with multiple subordinates, where the physical aggression of males becomes a contest for resources[32] (mates, territory, food). Female cichlids prefer to mate with a successfully alpha male with vivid coloration, whose territory has food readily available.

Moon wrasse

Some moon wrasses live in groups consisted of a dominant male, and a "harem" of about a dozen other wrasses, some female and some male.[35] The alpha male is more brightly colored, and at every low tide hour, changes from green to blue, and goes into a show of attacking and nipping all the other wrasses. This is his way of showing his dominance to the rest of the males and keeping the females in check. During breeding season and before high tide, the alpha male turns completely blue, gathers up every single female, and the spawning frenzy begins.

Mozambique tilapia

Mozambique tilapias often travel in groups where a strict dominance hierarchy is maintained. Positions within the hierarchy correlate with territoriality, courtship rate, nest size, aggression, and hormone production.[36] In terms of social structure, Mozambique tilapias engage in a system known as lek-breeding, where males establish territories with dominance hierarchies while females travel between them. Social hierarchies typically develop because of competition for limited resources including food, territories, or mates. During the breeding season, males cluster around certain territory, forming a dense aggregation in shallow water.[37] This aggregation forms the basis of the lek through which the females preferentially choose their mates. Reproductive success by males within the lek is highly correlated to social status and dominance.[38]

In experiments with captive tilapias, evidence demonstrates the formation of linear hierarchies where the alpha male participates in significantly more agonistic interactions. Thus, males that are higher ranked initiate much more aggressive acts than subordinate males. However, contrary to popular belief, Mozambique tilapias display more agonistic interactions towards fish that are farther apart in the hierarchy scale than they do towards individuals closer in rank. One hypothesis behind this action rests with the fact that aggressive actions are costly. In this context, members of this social system tend to avoid confrontations with neighboring ranks in order to conserve resources rather than engage in an unclear and risky fight. Instead, dominant individuals seek to bully subordinate tilapias both for an easy fight and to keep their rank.[39]

Seals

Elephant seals

Dominant male elephant seals arrive at potential breeding sites in spring, and fast to ensure that they can mate with as many females as possible.[40] Male elephant seals use fighting, vocal noises, and different positions to determine who will be deemed the dominant male.[40][41] When males reach eight to nine years of age, they have developed a pronounced long nose, in addition to a chest shield, which is thickened skin in their chest area.[40] They display their dominance by showing their noses, making loud vocalisations, and altering their postures.[40][41] They fight each other by raising themselves and ramming each other with their chests and teeth.[40]

When females arrive, the dominating males have already selected their territory on the beach.[40] Females cluster in groups called harems, which could consist of up to 50 females surrounding one alpha male.[40] Outside of these groups, a beta bull is normally roaming around on the beach.[40] The beta bull helps the alpha by preventing other males accessing the females.[40] In return, the beta bull might have an opportunity to mate with one of the females while the alpha is occupied.[40]

Canines

In the past, the prevailing view on gray wolf packs was that they consisted of individuals vying with each other for dominance, with dominant gray wolves being referred to as the "alpha" male and female, and the subordinates as "beta" and "omega" wolves. This terminology was first used in 1947 by Rudolf Schenkel of the University of Basel, who based his findings on researching the behavior of captive gray wolves.[42] This view on gray wolf pack dynamics was later popularized by the researcher L. David Mech in his 1970 book The Wolf. He later found additional evidence that the concept of an Alpha male may have been an interpretation of incomplete data and formally disavowed this terminology in 1999. He explained that it was heavily based on the behavior of captive packs consisting of unrelated individuals, an error reflecting the once prevailing view that wild pack formation occurred in winter among independent gray wolves. Later research on wild gray wolves revealed that the pack is usually a family consisting of a breeding pair and their offspring of the previous 1–3 years. In the article, Mech wrote that the use of the term "alpha" to describe the breeding pair adds no additional information, and is "no more appropriate than referring to a human parent or a doe deer as an alpha." He further notes the terminology falsely implies a "force-based dominance hierarchy." In 13 years of summer observations of wild wolves, he witnessed no dominance contests between them.[43]

In some other wild canids, the alpha male may not have exclusive access to the alpha female.[44] Other pack members as in the African painted dog (Lycaon pictus) may guard the maternity den used by the alpha female.[45]

Application to humans

The term "alpha male" is often incorrectly applied to any dominating man, especially bullies.[46] However, dominating behavior alone is rarely seen as a positive trait for either an ideal date or a romantic partner.[47] This misconception is common within the so-called "manosphere", especially in the pickup artist community.[48] The view that there is a dominance hierarchy among humans consisting of "alpha males" and "beta males" is sometimes reported in the mainstream media. Claims about women being "hard-wired" to desire "alpha males" are seen by experts as misogynistic and stereotypical, and are not supported by research.[49][50][51] No general classification of humans into a dominance hierarchy can be made, since human behavior and society are far more complex than that of other primates, and humans often take the dominant role in some social situations and a subordinate role in others.[50][51]

See also

References

  1. ↑ de Waal, Frans (2007). Chimpanzee Politics: Power and Sex Among Apes (25th Anniversary ed.). Baltimore, MD: JHU Press. ISBN 978-0-8018-8656-0. https://books.google.com/books?id=XsrhU2vV5PIC. 
  2. ↑ Letzter, Rafi (12 October 2016). "There's no such thing as an alpha male". https://www.businessinsider.com/no-such-thing-alpha-male-2016-10. 
  3. ↑ "Dominance hierarchy | animal behavior". https://www.britannica.com/science/dominance-hierarchy. 
  4. ↑ Wilson, David R.; Nelson, Ximena J.; Evans, Christopher S. (October 2009). "Seizing the Opportunity: Subordinate Male Fowl Respond Rapidly to Variation in Social Context" (in en). Ethology 115 (10): 996–1004. doi:10.1111/j.1439-0310.2009.01688.x. http://research.library.mun.ca/9779/1/2009_Wilson_et_al_Ethology.pdf. 
  5. ↑ Dutcher, Jim; Dutcher, Jamie (2019). Running with Wolves. National Geographic Books. pp. 115–119. ISBN 9781426333583. https://books.google.com/books?id=Ap9-DwAAQBAJ&q=lakota+omega+wolf&pg=PA115. 
  6. ↑ "The Omega Wolf". https://www.livingwithwolves.org/portfolio/the-omega/. 
  7. ↑ Foster, M.W. (2009). "Alpha male chimpanzee grooming patterns: implications for dominance "style"". American Journal of Primatology 2009 (2): 136–144. doi:10.1002/ajp.20632. PMID 19025996. 
  8. ↑ https://www.wired.com/2011/07/baboon-stress/
  9. ↑ https://www.newscientist.com/article/dn18366-why-alpha-male-baboons-allow-subordinates-sex-treats/
  10. ↑ 10.0 10.1 Tiddi, Barbara (2011). "Social relationships between adult females and the alpha male in wild tufted Capuchin monkeys". American Journal of Primatology 73 (8): 812–20. doi:10.1002/ajp.20939. PMID 21698660. 
  11. ↑ Foster, M; Gilby, I; Murray, C; Johnson, A; Wroblewski, E; Pusey, A (2009). "Alpha Male Chimpanzee Grooming Patterns: Implications for Dominance Style". American Journal of Primatology 71 (2): 136–144. doi:10.1002/ajp.20632. PMID 19025996. https://evolutionaryanthropology.duke.edu/sites/evolutionaryanthropology.duke.edu/files/Foster%20et%20al%202009%20Alhpa%20male%20chimapanzee%20styles.pdf. 
  12. ↑ Greshko, Michael (2017-01-30). "In Rare Killing, Chimpanzees Cannibalize Former Leader". National Geographic. http://news.nationalgeographic.com/2017/01/chimpanzees-murder-cannibalism-senegal/. 
  13. ↑ Whyte, Chelsea (2017-01-30). "Chimps beat up, murder and then cannibalize their former tyrant". New Scientist. https://www.newscientist.com/article/2119677-chimps-beat-up-murder-and-then-cannibalise-their-former-tyrant/. 
  14. ↑ "ChimpanZoo Homepage". http://www.chimpanzoo.org/african_notecards/chapter_11.html. 
  15. ↑ Noonan, Michael. "Inside a Chimpanzee Community". Canisius Ambassadors for Conservation. http://www.conservenature.org/learn_about_wildlife/chimpanzees/chimp_community.htm. 
  16. ↑ Cawthon Lang, Kristina (2010-12-01). "Primate Factsheets: Bonobo". Primate Info Net. http://pin.primate.wisc.edu/factsheets/entry/bonobo/behav. 
  17. ↑ Edwards, Lin (2012-03-02). "Female bonobos use homosexual sex to increase social status". https://phys.org/news/2012-03-female-bonobos-homosexual-sex-social.html. 
  18. ↑ Stoinski, T.S.; Rosenbaum, T.; Ngaboyamahina, T.; Vecellio, V.; Ndagijimana, F.; Fawcett, K. (2009). "Patterns of male reproductive behaviour in multi-male groups of mountain gorillas: examining theories of reproductive skew". Behaviour 146 (9): 1193–1215. doi:10.1163/156853909x419992. 
  19. ↑ Setchell, J. M.; Dixson A.F. (2001). "Changes in the Secondary Sexual Adornments of Male Mandrills (Mandrillus sphinx) Are Associated with Gain and Loss of Alpha Status". Hormones and Behavior 39 (3): 177–84. doi:10.1006/hbeh.2000.1628. PMID 11300708. 
  20. ↑ "Mask of the Mandrill". PBS. November 2006. https://www.pbs.org/wnet/nature/episodes/mask-of-the-mandrill/introduction/2351/. 
  21. ↑ Setchell, J. M.; Jean Wickings, E. (2005). "Dominance, status signals and coloration in male mandrills (Mandrillus sphinx)". Ethology 111: 25–50. doi:10.1111/j.1439-0310.2004.01054.x. 
  22. ↑ Dixson, A. F.; Bossi, T.; Wickings, E. J. (1993). "Male dominance and genetically determined reproductive success in the mandrill (Mandrillus sphinx)". Primates 34 (4): 525–532. doi:10.1007/BF02382663. 
  23. ↑ Setchell, J. M.; Dixson A.F. (2002). "Developmental Variables and Dominance Rank in Adolescent Male Mandrills (Mandrillus sphinx)". American Journal of Primatology 56 (1): 9–25. doi:10.1002/ajp.1060. PMID 11793410. 
  24. ↑ "The development of coordinated singing in cooperatively displaying long-tailed manakins". Behavior Ecology. 2002. 
  25. ↑ Webster, Michael S. (1994-10-01). "Female-defence polygyny in a Neotropical bird, the Montezuma oropendola" (in en). Animal Behaviour 48 (4): 779–794. doi:10.1006/anbe.1994.1302. ISSN 0003-3472. 
  26. ↑ 26.0 26.1 Malan, G.; Crowe, T. M.; Biggs, R.; Herholdt, J. J. (2008), "The social system of the Pale Chanting Goshawk Melierax canorus; monogamy v polyandry and delayed dispersal", Ibis 139 (2): 313–321, doi:10.1111/j.1474-919X.1997.tb04630.x  (Abstract only for non-subscribers.)
  27. ↑ Malan, Gerard (2005-10-01). "Reproductive partitioning among polyandrous alpha and beta pale chanting-goshawk males". African Zoology 40 (2): 213–222. doi:10.1080/15627020.2005.11407320. https://www.researchgate.net/publication/223995745. 
  28. ↑ Jenkins, A.R. Malan, G. & (1996-10-01). "Territory and nest defence in polyandrous pale chanting goshawks: do co breeders help?" (in en). African Zoology 31 (4). ISSN 1562-7020. https://journals.co.za/content/afzoo/31/4/AJA00445096_768. 
  29. ↑ 29.0 29.1 Shwartz, Mark (25 January 2007). "Study: Cichlids can determine their social rank by observation". Stanford University. http://news.stanford.edu/news/2007/january31/fishsr-013007.html. 
  30. ↑ Chen, Chun-Chun; Fernald, Russell D. (25 May 2011). "Visual Information Alone Changes Behavior and Physiology during Social Interactions in a Cichlid Fish (Astatotilapia burtoni)". PLOS ONE 6 (5): e20313. doi:10.1371/journal.pone.0020313. PMID 21633515. Bibcode: 2011PLoSO...620313C. 
  31. ↑ Knight, Kathryn (1 October 2015). "Fighting cichlids size up opposition with lateral line". Journal of Experimental Biology 218 (20): 3161. doi:10.1242/jeb.132563. 
  32. ↑ 32.0 32.1 Fernald, Russell D. (1 January 2017). "Cognitive skills and the evolution of social systems". Journal of Experimental Biology 220 (1): 103–113. doi:10.1242/jeb.142430. PMID 28057833. 
  33. ↑ Fernald, Russell D.; Kent, Kai R.; Hilliard, Austin T.; Becker, Lisa; Alcazar, Rosa M. (15 August 2016). "Two types of dominant male cichlid fish: behavioral and hormonal characteristics". Biology Open 5 (8): 1061–1071. doi:10.1242/bio.017640. PMID 27432479. 
  34. ↑ Arnott, Gareth; Ashton, Charlotte; Elwood, Robert W. (23 October 2011). "Lateralization of lateral displays in convict cichlids". Biology Letters 7 (5): 683–685. doi:10.1098/rsbl.2011.0328. PMID 21508024. 
  35. ↑ Allen, Gerald (2015). Reef Fish Identification Southern Pacific (second ed.). Jacksonville, Florida: New World Publications, Inc.. p. 225. ISBN 978-1-878348-60-9. 
  36. ↑ Oliveira, Rui F.; Vitor C. Almada; Adelino V. M. Canario (1996). "Social Modulation of Sex Steroid Concentrations in the Urine of Male Cichlid Fish Oreochromis mossambicus". Hormones and Behavior 30 (1): 2–12. doi:10.1006/hbeh.1996.0002. PMID 8724173. 
  37. ↑ Amorim, M. Clara P.; Almada, Vitor C. (1 March 2005). "The outcome of male–male encounters affects subsequent sound production during courtship in the cichlid fish Oreochromis mossambicus". Animal Behaviour 69 (3): 595–601. doi:10.1016/j.anbehav.2004.06.016. 
  38. ↑ Barata, Eduardo N.; Fine, Jared M.; Hubbard, Peter C.; Almeida, Olinda G.; Frade, Pedro; Sorensen, Peter W.; Canário, Adelino V. M. (1 April 2008). "A Sterol-Like Odorant in the Urine of Mozambique Tilapia Males Likely Signals Social Dominance to Females". Journal of Chemical Ecology 34 (4): 438–449. doi:10.1007/s10886-008-9458-7. PMID 18379847. 
  39. ↑ Oliveira, R.F.; V.C. Almada (1996). "Dominance hierarchies and social structure in captive groups of the Mozambique tilapia Oreochromis mossambicus (Teleostei Cichlidae)". Ethology Ecology & Evolution 8: 39–55. doi:10.1080/08927014.1996.9522934. 
  40. ↑ 40.0 40.1 40.2 40.3 40.4 40.5 40.6 40.7 40.8 40.9 Elephant seals. Friends of the Elephant Seal.. San Luis Obispo, Calif.: Central Coast Press. 1999. ISBN 9780965877695. OCLC 44446823. https://archive.org/details/elephantseals0000frie. 
  41. ↑ 41.0 41.1 Laws, R (1956). "The Elephant Seal: General, Social, and Reproductive Behavior". Falkland Islands Dependencies Survey 13. 
  42. ↑ "Schenkel's Classic Wolf Behavior Study Available in English". http://www.davemech.org/schenkel/. 
  43. ↑ Mech, L. David. (1999). "Alpha status, dominance, and division of labor in wolf packs". Canadian Journal of Zoology 77 (8): 1196–1203. doi:10.1139/z99-099. http://www.npwrc.usgs.gov/resource/2000/alstat/alstat.htm. 
  44. ↑ Greenberg & Haraway 1998
  45. ↑ Hogan, C. Michael (2009). "Painted Hunting Dog: Lycaon pictus". in N. Stromberg. http://globaltwitcher.auderis.se/artspec_information.asp?thingid=35993. 
  46. ↑ de Waal, Frans (2017). "The Surprising Science of Alpha Males" (in en). https://www.medpagetoday.com/tedmed/tedmed/84206. 
  47. ↑ Kaufman, Scott Barry (December 10, 2015). "The Myth of the Alpha Male". Greater Good Magazine. https://greatergood.berkeley.edu/article/item/the_myth_of_the_alpha_male. Retrieved May 18, 2021. 
  48. ↑ Ging, Debbie (2017-05-10). "Alphas, Betas, and Incels: Theorizing the Masculinities of the Manosphere:" (in en). Men and Masculinities. doi:10.1177/1097184X17706401. https://journals.sagepub.com/doi/10.1177/1097184X17706401. 
  49. ↑ Steadman, Ian (June 4, 2014). "The sexist pseudoscience of pick-up artists: the dangers of "alpha male" thinking". New Statesman. https://www.newstatesman.com/future-proof/2014/06/sexist-pseudoscience-pick-artists-dangers-alpha-male-thinking. 
  50. ↑ 50.0 50.1 Burnett, Dean (October 10, 2016). "Do alpha males even exist?" (in en). http://www.theguardian.com/science/brain-flapping/2016/oct/10/do-alpha-males-even-exist-donald-trump. 
  51. ↑ 51.0 51.1 Hosie, Rachel (May 9, 2017). "The Myth of the Alpha Male" (in en). https://www.independent.co.uk/life-style/myth-alpha-male-a7724971.html. 

Sources

Further reading




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