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<span id="zyzz"></span>[[File:Buff.jpg|thumb|right|One popular sex icon for men: Zyzz, died young of sudden cardiac arrest from too much steroid use to make himself look hyper-masculine. He was not a [[reproductive success]].]] | <span id="zyzz"></span>[[File:Buff.jpg|thumb|right|One popular sex icon for men: Zyzz, died young of sudden cardiac arrest from too much steroid use to make himself look hyper-masculine. He was not a [[reproductive success]].]] | ||
'''Fisherian runaway''' is a mechanism by which | '''Fisherian runaway''' is a mechanism by which [[sexual selection]] leads to exaggerated physical traits (ornamentation), potentially to the extent of [[maladaptiveness]] and reduced population viability,<ref>Encyclopedia of Ecology, By Brian D. Fath, page 316 https://books.google.com/books?hl=en&lr=&id=x1h7DwAAQBAJ&oi=fnd&pg=PA310&dq=%22fisherian+runaway%22+extinction+%22selection%22&ots=cq04BIA2Lf&sig=Otp5RbC3B_5W1ZR7Q3zGjPOe7uA#v=onepage&q=fisherian%20runaway&f</ref> or even extinction.<ref>The evolution of sexual strategy in modern humans: an interdisciplinary approach by Collins, Kendra Marie, https://studyres.com/doc/2550939/--california-state-university</ref><ref>Moen et al., 1999</ref> | ||
The name Fisherian runaway derives from the originator of the concept, Ronald Fisher, the 20th century British statistician, geneticist, eugenicist and racialist. | |||
== Animal examples == | == Animal examples == | ||
Despite there being debate on the role of sexual selection causing extinction without other factors present, everyone agrees that, combined with environmental factors, sexual selection can and does cause "evolutionary suicide" or extinction due to runaway selection.<ref>https://biology.stackexchange.com/questions/239/is-there-any-evidence-that-sexual-selection-may-lead-to-extinction-of-species</ref> | Despite there being debate on the role of sexual selection causing extinction without other factors present, everyone agrees that, combined with environmental factors, sexual selection can and does cause "evolutionary suicide" or extinction due to runaway selection.<ref>https://biology.stackexchange.com/questions/239/is-there-any-evidence-that-sexual-selection-may-lead-to-extinction-of-species</ref> | ||
Theoretic models suggest extinction cannot happen due to sexual selection without sudden environmental changes and as long the ornamented individual bears the cost.<ref>"Sexy to die for? Sexual selection and risk of extinction" by Hanna Kokko and Robert Brooks, Ann. Zool. Fennici 40: 207-219. [[https://www.jstor.org/stable/23736526 Abstract]]</ref> | Theoretic models suggest extinction cannot happen due to sexual selection without sudden environmental changes and as long the ornamented individual bears the cost.<ref>"Sexy to die for? Sexual selection and risk of extinction" by Hanna Kokko and Robert Brooks, Ann. Zool. Fennici 40: 207-219. [[https://www.jstor.org/stable/23736526 Abstract]]</ref> | ||
Certain species have been theorized to go extinct partly due to runaway female sexual selection. The Irish elk’s extinction was at least in part, due to runaway sexual selection. Female Irish elk selected male elk with larger bodies as well as increasingly larger antlers. Some recovered antlers measure nine feet across and weigh over 90 pounds. The extreme nutritious cost to grow such huge antlers, coupled with the burden of such a heavy load, were more than the males could handle, particularly as their food source density decreased during environmental changes.<ref>The evolution of sexual strategy in modern humans: an interdisciplinary approach by Collins, Kendra Marie, https://studyres.com/doc/2550939/--california-state-university</ref> In this case, natural selection would have favored males with smaller bodies and antlers needing fewer nutritional resources, however the sexual selection pressures were so strong, and had become so fixed in a positive feedback loop, that it ultimately cost the loss of the entire species.<ref>Moen et al., 1999</ref> | Certain species have been theorized to go extinct partly due to runaway female sexual selection. The Irish elk’s extinction was at least in part, due to runaway sexual selection. Female Irish elk selected male elk with larger bodies as well as increasingly larger antlers. Some recovered antlers measure nine feet across and weigh over 90 pounds. The extreme nutritious cost to grow such huge antlers, coupled with the burden of such a heavy load, were more than the males could handle, particularly as their food source density decreased during environmental changes.<ref>The evolution of sexual strategy in modern humans: an interdisciplinary approach by Collins, Kendra Marie, https://studyres.com/doc/2550939/--california-state-university</ref> In this case, natural selection would have favored males with smaller bodies and antlers needing fewer nutritional resources, however the sexual selection pressures were so strong, and had become so fixed in a positive feedback loop, that it ultimately cost the loss of the entire species.<ref>Moen et al., 1999</ref> | ||
<gallery mode="packed" widths="400" heights="200"> | <gallery mode="packed" widths="400" heights="200"> | ||
File:1920px-Male Peafowl (Peacock) at China National GeneBank, Shenzhen.jpg|A male Peafowl with completely useless plumage | File:1920px-Male Peafowl (Peacock) at China National GeneBank, Shenzhen.jpg|A male Peafowl with completely useless plumage | ||
File:Skull of Sabre-Toothed Tiger - Museum of Anthropology - La Paz - Baja California Sur - Mexico (23835305595).jpg| | File:Skull of Sabre-Toothed Tiger - Museum of Anthropology - La Paz - Baja California Sur - Mexico (23835305595).jpg|The Sabre-Toothed Tiger evolved comically large teeth | ||
File:Irish Elk Side.jpg|Skeleton of the Irish Elk | File:Irish Elk Side.jpg|Skeleton of the Irish Elk | ||
</gallery> | </gallery> | ||
Even though human females are more choosy in accordance to [[Bateman's principle]], both sexes are ornamented. Women have [[Boobs|permanently swollen breasts]], an hour glass shaped body etc., men have a V-shaped upper body, more toned muscles, beards, very large penises compared to other great apes, and [[:Category:Aesthetics|various other features]]. Both sexes have clearly defined [[Hairline|hairlines]] and very clear skin. None of these features | ==Humans== | ||
Even though human females are more choosy in accordance to [[Bateman's principle]], both sexes are ornamented. Women have [[Boobs|permanently swollen breasts]],<ref>https://doi.org/10.1016/j.evolhumbehav.2010.02.005</ref> an hour glass shaped body etc., men have a V-shaped upper body, more toned muscles, beards, very large penises compared to other great apes, and [[:Category:Aesthetics|various other features]].<ref>https://www.sciencedirect.com/science/article/abs/pii/S1090513810000279</ref> Both sexes have clearly defined [[Hairline|hairlines]] and very clear skin. None of these features have survival value besides being good looking, so they're likely sexually selected, likely mostly by aesthetic selection common to many higher animals,<ref>https://www.apa.org/monitor/oct06/pretty</ref> and possibly by feedback loops like Fisherian runaway and sensory bias,<ref>Fuller, R. C., Houle, D., & Travis, J. 2005. ''Sensory Bias as an Explanation for the Evolution of Mate Preferences.'' [[https://www.jstor.org/stable/10.1086/444443 Abstract]]</ref> leading to exaggeration and strengthened sexual dimorphism.<ref>https://www.sciencedirect.com/science/article/abs/pii/S1090513810000279</ref> Though dominant and masculine features like large beards and a deep, intimidating voice may also serve the intimidation of other males.<ref>https://www.sciencedirect.com/science/article/abs/pii/S1090513810000279</ref><ref>http://larspenke.eu/pdfs/Kordsmeyer_et_al_2018_-_Intra-_vs_intersexual_selection_on_human_males.pdf</ref> | |||
The fact that men have only reproduced half as often as women<ref>https://incels.wiki/w/Scientific_Blackpill#Before_.27enforced_monogamy.27.2C_women.27s_effective_population_size_was_up_to_17x_larger_than_men.27s</ref> suggests only the most dominant men were involved in selecting women's ornament. | |||
==Explanation== | ==Explanation== | ||
=== Mechanism === | === Mechanism === | ||
[[File:Peacock courting peahen.jpg|alt=|thumb|"The females may be dull looking, but they're very picky." A peacock courting a peahen]] | [[File:Peacock courting peahen.jpg|alt=|thumb|"The females may be dull looking, but they're very picky." A peacock courting a peahen]] | ||
Fisherian runaway is a selection process occurring over many generations, in which the one sex (either male or female) becomes more choosy about a heritable trait for the simple reason that it will make the offspring more attractive. As the the choosiness for the trait increases, the selective pressure to prefer the trait increases too, forming a [https://en.wikipedia.org/wiki/Positive_feedback_loop positive feedback loop]. In response to the increased choosiness, the other sex evolves to enlarge, overcomplicate or beautify that trait in efforts of becoming more attractive, eliciting [https://en.wikipedia.org/wiki/Supernormal_stimulus super-stimuli] in the opposite sex. The exponential nature of positive feedback loops exerts a strong selection pressure that the resulting exaggerate may reduce mobility and increase vulnerability to predators and to sudden environmental changes. | |||
Since females are [[Bateman's principle|more choosy]] in many species throughout the animal kingdom (including humans), the males tend to be more ornamented. | |||
=== Initiation === | === Initiation === | ||
Such feedback loops can be initiated by arbitrary aesthetic selection, but also when a trait is slightly correlated with fitness (e.g. health), or when a trait is similar in appearance to attractive or otherwise valuable objects or body parts.<ref>Fuller, R. C., Houle, D., & Travis, J. 2005. ''Sensory Bias as an Explanation for the Evolution of Mate Preferences.'' [[https://www.jstor.org/stable/10.1086/444443 Abstract]], p. 444</ref> For example, women's breasts may have evolved to mimic their buttocks because the latter was already a sexually attractive body part before humans developed upright posture, and then Fisherian runaway may have lead to breasts becoming increasingly larger and increasingly attractive to men. | Such feedback loops can be initiated by arbitrary aesthetic selection, but also when a trait is slightly correlated with fitness (e.g. health), or when a trait is similar in appearance to attractive or otherwise valuable objects or body parts.<ref>Fuller, R. C., Houle, D., & Travis, J. 2005. ''Sensory Bias as an Explanation for the Evolution of Mate Preferences.'' [[https://www.jstor.org/stable/10.1086/444443 Abstract]], p. 444</ref> For example, women's breasts may have evolved to mimic their buttocks because the latter was already a sexually attractive body part before humans developed upright posture, and then Fisherian runaway may have lead to breasts becoming increasingly larger and increasingly attractive to men. | ||
=== Beauty === | |||
Feedback loops like Fisherian runaway may have played a role in the evolution of beauty. Beauty could have evolved simply by sexual selection, i.e. mate selection favoring objective [[beauty]] (simplicity). But feedback loops as mentioned above may have exaggerated aspects of it, leading to increased sexual dimorphism and amplified and narrowed the attraction to specific kinds of beautiful physical traits. This also stabilizes the phenotype, making it harder to adapt to environmental changes. Any sort of [[sexual dimorphism]], whether behavioral or ornamental likely tends to get reinforced by such feedback loops because [[sexual dimorphism]] is inherently attractive.<ref>https://incels.wiki/w/Scientific_Blackpill#Even_chickens_prefer_sexually_dimorphic_human_faces.2C_to_the_same_extent_as_humans</ref> | |||
While it is not proven that feedback loops were involved in shaping human ornament, or just sexual selection without feedback, it is certainly plausible, especially considering the importance people place on good looks. It could explain why people undergo great risks and costs merely for improving their looks, e.g. by surgeries, diets or steroid intake (see [[#zyzz|Zyzz's photo]]). It could also explain the phenomenon of being ''stunned'' by someone's appearance, as well as "love on first sight" and [[oneitis]]. | |||
=== | === Intelligence === | ||
Miller suggested strong positive-feedback processes in sexual selection to have given rise to higher human cognition, which he regards as too complex. Much of male courtship may consists in eliciting super stimuli in women by cognitive performance such as poetry, dancing, art and humor.<ref>https://ontherapyaspse.files.wordpress.com/2012/04/geoffrey-miller-the-mating-mind.pdf</ref> | |||
==Criticism== | |||
===Good Genes Hypothesis=== | |||
Also called ''Zahavi's handicap principle'', this claims the exaggerated ornament is a costly and hence a reliable signal of other desirable traits. For example, a peacock with a very large tail would be easy prey (which is costly), and thus would most likely have other good traits that make up for this handicap (good genes). There is, however, little supporting scientific evidence. In humans in particular, beauty and ornament is not strongly correlated with health at all (those it is weakly), and even less with cognitive ability.<ref>https://incels.wiki/w/Scientific_Blackpill#Attractive_people_are_perceived_much_more_positively_than_they_really_are</ref> | |||
=== | ===Environmental factors and extinction=== | ||
Base sexual preference of an entire species can make them more likely to go extinct.<ref>https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2656.12601</ref><ref>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1691875/</ref><ref>https://www.sciencedaily.com/releases/2018/04/180411131646.htm</ref><ref>https://www.nature.com/articles/d41586-018-04059-7</ref> But the runaway selection of the most exaggerated members alone, arguably cannot cause the entire species to go extinct. However, together with environmental factors, runaway female selection has played a role in extinction, for example in the the Irish Elk.<ref>The evolution of sexual strategy in modern humans: an interdisciplinary approach by Collins, Kendra Marie, https://studyres.com/doc/2550939/--california-state-university</ref><ref>Moen et al., 1999</ref> | |||
There are scientific models that show under a stable environment, a feedback loop can develop where male intrasexual competition leads to a linear increase in size dimorphism, outstripping the ability of the environment to to support this increased size.<ref>http://www.jstor.org/stable/2410506</ref> | |||
== Female mate choice== | |||
=== Sexy son hypothesis === | |||
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The ''sexy son hypothesis'' was also proposed by Fisher and considers runaway sexual selection of men's [[looks]] and sexiness. It simply states that the positive feedback loop can make women so attracted to male ornament that women will choose a very good looking male regardless of other considerations such as morality or paternal investment, because the male's ornament—which is partly heritable—confers on their offspring a potential reproductive advantage.<ref>https://academic.oup.com/beheco/article/19/2/456/214088</ref> This is particularly staggering in women, otherwise [[libido|coy]], engaging in casual sex with men way above their league (i.e. getting [[pump and dump|pumped and dumped]]). | |||
Since women heavily depended on men's provision, only a [[Chad|tiny percentage]] of men is good looking enough that they can skip women's typical coy waiting time (around 4%, compared to 60-70% for men choosing women).<ref>https://incels.wiki/w/Scientific_Blackpill#Men_like_61.9.25_of_female_profiles.2C_women_like_only_4.5.25_of_male_profiles</ref> | |||
Women would also much more readily forego using a condom with a good looking mate.<ref>https://incels.wiki/w/Scientific_Blackpill#Women_are_less_likely_to_use_a_condom_with_a_more_attractive_male_partner</ref> Of course, men also more readily copulate with sexy women, but men have less [[Bateman's principle|parental investment]] and hence do not need to care as much about such considerations (as evidenced by men's much higher inclination to copulate with a random stranger, i.e. lower standards for casual sex; men are also more choosy when they actually have to provide). | |||
Hence, for women, copulating only based on sexiness has more drastic implications, hence people care less about the "sexy daughters" phenomenon. However, arguably, a similarly risky strategy for men is raping a sexy woman (to produce sexy daughters as a promising vehicle of their own genes). Both are irresponsible and socially parasitic as they depend on others investing in the offspring (in modern societies via taxes). Engaging in [[alpha fuxx, beta buxx]], the woman risks not being provided for. Engaging in rape, the man risks death and exile and also won't provide for the offspring. But provided some do engage in these strategies, may mean such sexual strategies have evolved because better looking offspring can make up for these risks on average (in terms of evolutionary fitness). | |||
{{#ev:youtube|https://www.youtube.com/watch?v=idc_XZpB0h0|frame|}} | |||
{{#ev:youtube|https://www.youtube.com/watch?v=kXrkgPgt234|frame|}} | |||
=== | === Is female mate choice maladaptive? === | ||
Various members of the [[MRA]] hypothesized that the increasingly dimorphic beauty standards that men are expected to have just to get a date in a sexually liberated online [[dating]] environment may be the beginning of a Fisherian runaway or intensification of existing ones. Only a very small percentage of men are being chosen, and it's the men with the most sexually dimorphic traits: cartoonishly large muscles and frame, with no selective attention paid to traits like loyalty, intelligence, etc. | |||
This also results in an even higher competitive environment among men without physically sexually dimorphic traits, and men with [[dark triad]] traits getting even more to win female attention, exaggerating a trait which arguably became [[Maladaptiveness|maladaptive]] after civilization and the industrial revolution. Of course this possibility is a concerning trend even without Fisherian runaway possibly intensifying such selection patterns in future generations. | |||
Men's rights activist [[Warren Farrell]] warned of such a thing in 1993, in his book, [[The Myth of Male Power]], warning women that their preference for and [[Cheerleaders|encouragement]] of, "hunter-killer", "star quarterback", type men could cause the extinction of the human race with the arrival of nuclear technology. He also claimed that since civilization and the industrial revolution [[dark triad]] traits have become maladaptive, as the traits which foster a healthy society have switched from might-makes-right individual brutality, to [[Nice guy|cooperation, intelligence, empathy]] etc. | |||
Research on sexual selection theory by Puts (2010) suggested women's preference for highly dominant men may have partly been a result of sexual selection.<ref>https://www.tandfonline.com/doi/abs/10.1080/07418825.2016.1216153?journalCode=rjqy20</ref><ref>https://doi.org/10.1016/j.evolhumbehav.2010.02.005</ref> | |||
<gallery mode="packed" widths="400" heights="400"> | <gallery mode="packed" widths="400" heights="400"> | ||
File:Gigachad500.jpg|Typical human male after 500 years of unconstrained female sexuality | File:Gigachad500.jpg|Typical human male after 500 years of unconstrained female sexuality | ||