Sexe, genre et évolution : dimorphisme sexuel

Pour les questions liées à la division du travail dans les sociétés paléolithiques, j’ai créé une nouvelle page.

[Retour au sommaire des données scientifiques]

Evolution du dimorphisme de poids et de taille

[Nouvelle Page]

Autres dimorphismes

Sex differences in the pelvis did not evolve de novo in modern humans
Fischer et al.
Nature ecology & evolution, 2021

It is commonly assumed that the strong sexual dimorphism of the human pelvis evolved for delivering the relatively large human foetuses. Here we compare pelvic sex differences across modern humans and chimpanzees using a comprehensive geometric morphometric approach. Even though the magnitude of sex differences in pelvis shape was two times larger in humans than in chimpanzees, we found that the pattern is almost identical in the two species. We conclude that this pattern of pelvic sex differences did not evolve de novo in modern humans and must have been present in the common ancestor of humans and chimpanzees, and thus also in the extinct Homo species. We further suggest that this shared pattern was already present in early mammals and propose a hypothesis of facilitated variation as an explanation: the conserved mammalian endocrine system strongly constrains the evolution of the pattern of pelvic differences but enables rapid evolutionary change of the magnitude of sexual dimorphism, which in turn facilitated the rapid increase in hominin brain size.

Bilateral asymmetry and developmental plasticity of the humerus in modern humans
Zelazny et al.
American journal of physical anthropology, 2021

Hunter‐gatherers from Indian Knoll have significantly higher levels of asymmetry than other groups and are more sexually dimorphic, particularly in cross‐sectional properties of the diaphysis.

Impact Protection Potential of Mammalian Hair: Testing the Pugilism Hypothesis for the Evolution of Human Facial Hair
Beseris et al.
Integrative organismal biology, 2021

Because facial hair is one of the most sexually dimorphic features of humans (Homo sapiens) and is often perceived as an indicator of masculinity and social dominance, human facial hair has been suggested to play a role in male contest competition. Some authors have proposed that the beard may function similar to the long hair of a lion’s mane, serving to protect vital areas like the throat and jaw from lethal attacks. This is consistent with the observation that the mandible, which is superficially covered by the beard, is one of the most commonly fractured facial bones in interpersonal violence. We hypothesized that beards protect the skin and bones of the face when human males fight by absorbing and dispersing the energy of a blunt impact.

Sexual Dimorphism in the Functional Development of the Cochlear Amplifier in Humans [Abstract]
Mishra et al.
Ear and hearing, 2021

Male children showed a significant reduction in otoacoustic emission magnitudes with age, whereas female children did not show any such changes. Females showed higher stimulus-frequency otoacoustic emission magnitudes compared with males. However, the effect size of sex differences in young adults was larger compared with children. Unlike the otoacoustic emission magnitude, the noise floor did not show sexual dimorphism; however, it decreased with age.

Expanding the evolutionary explanations for sex differences in the human skeleton
Holly M. Dunsworth
Evolutionnary anthropology, 2020

While the anatomy and physiology of human reproduction differ between the sexes, the effects of hormones on skeletal growth do not. Human bone growth depends on estrogen. Greater estrogen produced by ovaries causes bones in female bodies to fuse before males’ resulting in sex differences in adult height and mass. Female pelves expand more than males’ due to estrogen and relaxin produced and employed by the tissues of the pelvic region and potentially also due to greater internal space occupied by female gonads and genitals.

False dichotomies and human sexual size dimorphism: A comment of Dunsworth (2020)
Font & Carazo
Evolution and human behavior, 2020

Sexual dimorphism in human arm power and force: implications for sexual selection on fighting ability
Morris et al.
Journal of experimental biology, 2020

our results indicate the presence of pronounced male-biased sexual dimorphism in muscle performance for protracting the arm to propel the fist forward. We also compared overhead pulling force between males and females, to test the alternative hypothesis that sexual dimorphism in the upper body of humans is a result of selection on male overhead throwing ability. We found weaker support for this hypothesis, with less pronounced sexual dimorphism in overhead arm pulling force. The results of this study add to a set of recently identified characters indicating that sexual selection on male aggressive performance has played a role in the evolution of the human musculoskeletal system and the evolution of sexual dimorphism in hominins.

Evolution built men to pack a punch
Kathrin Knith
Journal of experimental biology, 2020

The Performance Gap in Sport Can Help Determine Which Movements Were Most Essential to Human Evolution
Colin Carroll
Frontiers in physiology, 2019

This difference suggests that general sexual dimorphism does not explain why female performance is relatively closer to male performance at some track and field events than others. We hypothesize that this trend can be explained by the presence of sex-blind musculoskeletal adaptations (SBMA’s), which accumulate over generations to reduce the size of the PG in certain movements. We conclude that the selection trend favoring in humans should be explored further to determine whether the PG in sport can indeed be used to determine movements to which the human body is adapted.

Cochlear shape reveals that the human organ of hearing is sex-typed from birth [Texte]
Braga et al.
Nature scientific reports, 2019

Sexual Dimorphism in Hominin Ancestors
J. Michael Plavcan
The international encyclopedia of anthropology, 2018

The fossil record suggests that the earliest known hominin—Ardipithecus ramidus—showed little size or canine dimorphism. Later australopithecines show modest to strong dimorphism, with dimorphism approaching modern human levels in Homo erectus and Homo heidelbergensis. Behavioral inferences based on dimorphism are uncertain, but strong dimorphism in Australopithecus suggests polygynous mating, with strong male competition. Changes in dimorphism and body size suggest changes in female life history and associated patterns of male competition. Finally, the reevolution of dimorphism in hominins suggests that the modern human condition is derived and not inherited from the common ancestor of Homo and Pan.

On The Evolution of The Sex Differences in Throwing: Throwing is a Male Adaptation in Humans
Lombardo & Deaner
The quarterly review of biology, 2018

The development of the ability to throw projectiles for distance, speed, and accuracy was a watershed event in human evolution. We hypothesize that throwing first arose in threat displays and during fighting and later was incorporated into hunting by members of the Homo lineage because nonhuman primates often throw projectiles during agonistic interactions and only rarely in attempts to subdue prey. Males, who threw more often than females in both combat and hunting, would have been under stronger selection than females to become proficient at the ability to throw, intercept, and dodge projectiles as throwing skills became critical to success in combat and hunting. Therefore, we predict that males, more than females, should display innate anatomical and behavioral traits associated with throwing. We use data from a variety of disciplines to discuss: the sex differences in throwing speed, distance, and accuracy; sex differences in the development of the throwing motion; inability of training or cultural influences to erase the sex differences in throwing; sex differences in the use of throwing in sports, combat, and hunting; and sex differences in anatomical traits associated with throwing that are partly responsible for male throwing superiority. These data contradict the view held by many commentators that socialization rather than innate sex differences in ability are primarily responsible for male throwing superiority. We suggest that throwing is a male adaptation.

Sexual Dimorphism
Mori et al.
Encyclopedia of Animal Cognition and Behavior, 2017 non cliquable, copier l’URL)

Homo sapiens shows an adult male-to-female body weight of about 1.1–1.2; on average, males are taller than females, with a ratio of 1.06 ; they are also more muscular, have larger heart and lungs, a greater number of red cells in blood, and a beard (Dixon2009). Also, males with a broad chest and shoulders, narrow hips, and a muscular torso tend to be considered attractive partners by females, so that sexual selection comes into play. Conversely, females invest more in the production and storage of fat, mainly deposited around buttocks, hips, thighs, and breast, as a result of estrogen action, when they become mature reproductively (Pond1998). In fact, fat reserves are crucial for reproduction and it makes sense their positive selection in evolutionary terms, as they are honest signals of reproductive potential. There are quite a few other signs of sexual dimorphism in Homo sapiens, relevant to skin color, craniofacial traits, and voice pitch, some of them dependent on differential hormone actions during development. All these features make the human species a remarkably dimorphic one.

Gorillas in Our Midst? Human Sexual Dimorphism and Contest Competition in Men
Hill et al.
On human nature, 2017

The literature on human sexual selection has historically focused on the role of female mate choice, but cumulating experimental, correlational, and cross-cultural evidence suggests that male contest competition may have been more influential in shaping men’s phenotypes. Cross-species comparison has shown similarities between humans and our closest extant phylogenetic relatives, the Great Apes, in male–male aggression, and archeological evidence also indicates a great antiquity for male–male violence. Compared to women, men possess substantially greater muscle mass, strength, cranial robusticity, physical aggression, pain tolerance, risk-taking, weapons use, and participation in coalitional aggression. Men also exhibit displays of physical prowess and acuity to the formidability of male conspecifics, as well as possessing a suite of traits, such as facial hair and low vocal pitch, that increase perceptions of dominance. These traits are consistent with having been shaped by contest competition over mates: they are sexually dimorphic, appear at sexual maturity, and predict success in male contests as well as success in mating and reproduction. While alternative explanations for some of these sexually dimorphic traits are possible, contest competition among males throughout human evolutionary history is the most parsimonious.

Sexual competition among women : a review of theory and supporting evidence
Arnocky & Vaillancourt
The oxford handbook of women and competition, 2017

Arnocky 2017 sexual competition among women

Sexual selection on male vocal fundamental frequency in humans and other anthropoids
Puts et al.
Proceedings of the Royal Society B, 2016

In many primates, including humans, the vocalizations of males and females differ dramatically, with male vocalizations and vocal anatomy often seeming to exaggerate apparent body size. These traits may be favoured by sexual selection because low-frequency male vocalizations intimidate rivals and/or attract females, but this hypothesis has not been systematically tested across primates, nor is it clear why competitors and potential mates should attend to vocalization frequencies. Here we show across anthropoids that sexual dimorphism in fundamental frequency (F0) increased during evolutionary transitions towards polygyny, and decreased during transitions towards monogamy. Surprisingly, humans exhibit greater F0 sexual dimorphism than any other ape. We also show that low-F0 vocalizations predict perceptions of men’s dominance and attractiveness, and predict hormone profiles (low cortisol and high testosterone) related to immune function. These results suggest that low male F0 signals condition to competitors and mates, and evolved in male anthropoids in response to the intensity of mating competition.

Les chimpanzés mâles commettent plus de meurtres que les chimpanzés femelles. Les victimes sont plus souvent des mâles, mais les chimpanzés mâles tuent aussi des femelles. Ces chiffres sont assez proches de ce que l’on retrouve chez l’humain.

Lethal aggression in Pan is better explained by adaptive strategies than human impacts
Wilson et al.
Nature, 2014

Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. Two kinds of hypothesis have been proposed. Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates1,2,3,4,5. Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning6,7,8,9. To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported.

A rapprocher de ce qu’on trouve chez les humains :

Cliquer pour accéder à 2014_GLOBAL_HOMICIDE_BOOK_web.pdf

“I sing of arms and of a man…”: medial epicondylosis and the sexual division of labour in prehistoric Europe
Villotte & Knüsel
Journal of archeological science, 2014

This indicates that males, but not females, preferentially employed movements involving throwing motions in these hunter-gatherer and early farming groups. Based on this evidence we postulate the existence of a persistent sexual division of labour in these prehistoric European populations involving one or several strenuous activities linked to unilateral limb use.

The importance of physical strength for males
Sell et al.
Human nature, 2012

Fighting ability, although recognized as fundamental to intrasexual competition in many nonhuman species, has received little attention as an explanatory variable in the social sciences. Multiple lines of evidence from archaeology, criminology, anthropology, physiology, and psychology suggest that fighting ability was a crucial aspect of intrasexual competition for ancestral human males, and this has contributed to the evolution of numerous physical and psychological sex differences. Because fighting ability was relevant to many domains of interaction, male psychology should have evolved such that a man’s attitudes and behavioral responses are calibrated according to his formidability. Data are reviewed showing that better fighters feel entitled to better outcomes, set lower thresholds for anger/aggression, have self-favoring political attitudes, and believe more in the utility of warfare. New data are presented showing that among Hollywood actors, those selected for their physical strength (i.e., action stars) are more likely to believe in the utility of warfare.

Men physical strenght

Osteological clues for the presence of a sexual division of labour in the Eurasian Middle Paleolithic
Japp Saers
Leiden university, 2011

In this bachelor thesis I investigate whether Neanderthals had a sexual division of labour or not. I established three hypotheses: 1) Neanderthals had a sexual division of labour where males hunt and females gather plant foods and perform other activities, 2) Neanderthals had a sexual division of labour where males and females hunt but males perform the most dangerous tasks, 3) there was no sexual division of labour and males and females hunted and gathered in equal amounts. To find out if Neanderthals had a sexual division of labour, a meta-study of two osteological analyses applied to Neanderthal bones was performed. The first methods that was used was a comparison of the shape and robusticity of male and female Neanderthal limb bones compared to samples of modern human hunter-gatherers and sedentary populations. Secondly the distribution of trauma across the skeletons of male and female Neanderthals was compared. In both of the analyses the evidence pointed towards the first hypothesis. The evidence however was too limited. The small sample size of sexable Neanderthals was the largest issue. I concluded that according to the data gathered in this thesis hypothesis 1 is the most likely. However, none of the three hypotheses can be rejected confidently due to the limited evidence.

Identifying and explaining apparent universal sex differences in cognition and behavior
Lee Ellis
Personality and individual differences, 2011

With growing recognition that there are universal sex differences in cognition and behavior, four theories have been proposed to account for these differences: the founder effect theory, the social structuralist theory, the evolutionary theory, and the evolutionary neuroandrogenic (ENA) theory. The latter of these theories is described in considerable detail as offering an explanation for most of 65 recently identified apparent universal sex differences (AUSDs) in cognition and behavior. Regarding “ultimate causes” (why), ENA theory asserts that (a) evolutionary-genetic factors incline females to bias their mate choices toward males who are loyal and competent provisioners of resources and (b) males are merely a genetic variant on the female sex selected for responding to female mating biases. In terms of “proximate causes” (how), the theory maintains that high exposure to androgens has evolved to alter the male brain functioning in two specific ways relative to most female brains: (a) suboptimal arousal and (b) a rightward shift in neocortical functioning. These two functional patterns are described and hypothesized to incline males and females to learn differently in many respects. The most fundamental differences involve males learning ways of either complying with or circumventing female mate preferences. Numerous universal sex differences in cognition and behavior are hypothesized to result from these evolved neurohormonal factors, including most of the 65 AUSDs herein summarized in seven categorical tables.

Sex differences in chimpanzees’ use of sticks as play objects resemble those of children
Kahlenberg & Wrangham
Current Biology, 2010

Sex differences in children’s toy play are robust and similar across cultures 1, 2. They include girls tending to play more with dolls and boys more with wheeled toys and pretend weaponry. This pattern is explained by socialization by elders and peers, male rejection of opposite-sex behavior and innate sex differences in activity preferences that are facilitated by specific toys [1]. Evidence for biological factors is controversial but mounting. For instance, girls who have been exposed to high fetal androgen levels are known to make relatively masculine toy choices [3]. Also, when presented with sex-stereotyped human toys, captive female monkeys play more with typically feminine toys, whereas male monkeys play more with masculine toys [1]. In human and nonhuman primates, juvenile females demonstrate a greater interest in infants, and males in rough-and-tumble play. This sex difference in activity preferences parallels adult behavior and may contribute to differences in toy play [1]. Here, we present the first evidence of sex differences in use of play objects in a wild primate, in chimpanzees (Pan troglodytes). We find that juveniles tend to carry sticks in a manner suggestive of rudimentary doll play and, as in children and captive monkeys, this behavior is more common in females than in males.

Male chimpanzees exchange political support for mating opportunities
Duffy et al.
Current biology, 2007

Male chimpanzees, Pan troglodytes, differ from males in most other mammalian taxa because they remain in their natal communities throughout their lives, form close bonds with one another, and cooperate in a range of activities [1]. However, males also compete fiercely for status within their groups 2, 3, and high rank enhances male reproductive success 4, 5. Males rely partly on coalitions to achieve and maintain status 2, 3, 6, 7, 8, 9, and shifts in male alliances can have dramatic political effects 2, 3, 6. It is not known what benefits are obtained by low-ranking coalition partners. Here we report that the highest-ranking (alpha) male in one well-studied community of chimpanzees rewarded his allies by allowing them preferential access to mates.

Sexual dimorphism in primate evolution
J. Michael Plavcan
American journal of physical anthropology, 2002

In contrast to the canine teeth, dimorphism inhominid body mass was apparently quite substan-tial. McHenry (1992, 1994a,b) provides data sug-gesting that body mass dimorphism in early homin-ids ranged from comparable to a chimpanzee inAustralopithecus robustus,to quite gorilla-like inA.boisei(Plavcan and van Schaik, 1997a). Interest-ingly, the data of McHenry (1992, 1994a,b) suggestthatHomo erectus,considered as a single species,could have shown substantial body size dimorphism.However, if traditionalH. erectusis split intoH.erectus sensu strictoandH. ergaster,then the levelsof dimorphism are reduced to levels more compara-ble to modern humans. Regardless, analyses of theface and skeletal elements of early hominids all sug-gest that body mass dimorphism in these animalswas substantial

Variation in human body size and shape
Christopher Ruff
Annual review of anthropology, 2002

Dimorphisme australopithèque et Homo Ruff 2002

(Cité par Priscille Touraille)

Male strategies and Plio-Pleistocene archaeology
O’Connell et al.
Journal of human evolution, 2002

Cliquer pour accéder à ebd7d1c26d499f3a98e68e1573d0f81e0578.pdf

Archaeological data are frequently cited in support of the idea that big game hunting drove the evolution of early Homo, mainly through its role in offspring provisioning. This argument has been disputed on two grounds: (1) ethnographic observations on modern foragers show that although hunting may contribute a large fraction of the overall diet, it is an unreliable day-to-day food source, pursued more for status than subsistence; (2) archaeological evidence from the Plio-Pleistocene, coincident with the emergence of Homo can be read to reflect low-yield scavenging, not hunting. Our review of the archaeology yields results consistent with these critiques: (1) early humans acquired large-bodied ungulates primarily by aggressive scavenging, not hunting; (2) meat was consumed at or near the point of acquisition, not at home bases, as the hunting hypothesis requires; (3) carcasses were taken at highly variable rates and in varying degrees of completeness, making meat from big game an even less reliable food source than it is among modern foragers. Collectively, Plio-Pleistocene site location and assemblage composition are consistent with the hypothesis that large carcasses were taken not for purposes of provisioning, but in the context of competitive male displays. Even if meat were acquired more reliably than the archaeology indicates, its consumption cannot account for the significant changes in life history now seen to distinguish early humans from ancestral australopiths. The coincidence between the earliest dates for Homo ergaster and an increase in the archaeological visibility of meat eating that many find so provocative instead reflects: (1) changes in the structure of the environment that concentrated scavenging opportunities in space, making evidence of their pursuit more obvious to archaeologists; (2) H. ergaster‘s larger body size (itself a consequence of other factors), which improved its ability at interference competition.

Grosse synthèse du dimorphisme chez les primates, et de ses causes possibles.

Size, sexual dimorphism, and polygyny in primates
J. Michael Plavcan
Yearbook of physical anthropology, 2001

Sex differences in throwing: monkeys having a fling
Neil V. Watson
Trends in cognitive sciences, 2001

Fast and accurate throwing was undoubtedly important to ancestral hominids, and was subject to sexual-selection pressures that generated a male advantage in throwing accuracy that persists in modern humans. The balance of evidence, including that from a recent comparative study of throwing in humans and capuchin monkeys, suggests that high-performance throwing involves unique adaptations in the domains of spatial targeting, precision timing, and multi-joint motor control.

Sexual dimorphism in relation to big-game hunting and economy in modern human populations
Stephen Collier
American journal of physical anthropology, 1993

the big‐game hunting (whaling) Eskimos had the lower multivariate dimorphism in the humerus, which could be expected to be the structure under greatest exertion by such hunting in males. While the exertions of the whale hunting economic activities led to high skeletal robusticity, as predicted by Frayer’s model, this was true of the females as well as the males, resulting in low sexual dimorphism in some features. Females are half the sexual dimorphism equation, and they cannot be seen as constants in any model of economic behavior.

(Cité par Priscille Touraille)

Human marriage systems and sexual dimorphism in stature
Gaulin & Bauster
American Journal of Physical Anthropology, 1992

Contemporary populations of Homo sapiens are sexually dimorphic on a variety of traits. In terms of stature, men are reliably between 4% and 10% taller than women in well‐sampled human populations. Are cross‐cultural differences in the magnitude of sexual dimorphism consistent with expectations from sexual selection theory? Prior studies have provided conflicting answers to this question in part because they failed to agree on how the force of sexual selection should or could be operationalized. Here we offer a simple and unbiased method for operationalizing sexual selection and retest two separate predictions from earlier work (Alexander et al., 1979) about its expected impact on stature dimorphism in a sample of 155 societies. Neither prediction matches the observed cross‐cultural distribution of dimorphism. However, this is not the consequence of a random distribution of dimorphism across societies. Instead, the data exhibit a robust and unexpected pattern.

Female subsistence strategies among Ache hunter–gatherers of eastern Paraguay.
Hum Ecol. 1985

(cité par Priscille Touraille)

Size, Sexual Dimorphism, and Polygyny in Primates, in Size and Scaling in Primate Biology
T. H. Clutton-Brock
Advances in primatology, 1985

Among primates, the extent of sexual dimorphism in body size ranges from species where mature females are slightly larger than mature males, as in some of the marmosets and tamarins (Ralls, 1976), through species where males are slightly larger than females, like many of the diurnal lemurs and the arboreal colobines, to those where males are nearly twice as heavy as females, as in the larger cercopithecines, the gorilla and the orang (Clutton-Brock and Harvey, 1978). The tendency for polygynous mammals to show greater size dimorphism than monogamous ones was originally noticed by Darwin (1871), and quantitative studies have subsequently confirmed that in primates (Gautier-Hion, 1975; Clutton-Brock et al., 1977; Clutton-Brock and Harvey, 1978)

(cité par Priscille Touraille)

Cross-cultural differences in sexual dimorphism: Is there any variance to be explained?
Gaulin & Boster
Ethology and sociobiology, 1985

Some argue that cross-cultural variation in sexual dimorphism is associated with marriage practices whereas others suggest it is a function of absolute size. We reject both explanations, noting that the degree of dimorphism in humans is very consistent and the observed variance is mainly a function of sample size.

(cité par Priscille Touraille)

Subsistence practices and human sexual dimorphism of stature
Wolfe & Gray
Journal of human evolution, 1982

Hypotheses recently advanced by Brace & Ryan (1980) and Frayer (1980) suggest links between changes in human sexual dimorphism and changes in technology and subsistence practices. In this paper we test these hypotheses using a sample of extant human groups. Results indicate that extant agriculturalists exhibit a greater degree of sexual dimorphism in stature than extant hunter-gatherers. Moreover, the data analysed in this paper do not indicate that a more equal division of labor is associated with a decrease in human height sexual dimorphism.

Sexual differences in Neanderthal limb bones
Eric Trinkaus
Journal of human evolution, 1980

Neanderthal sexual size dimorphism, both within single site samples and in the total sexable sample, is virtually the same as that of recent human samples. Furthermore, despite a tendency towards more robust limbs, the Neanderthals exhibit sexual dimorphism in limb bone shaft and articular robusticity similar to that of recent human samples. By the time of the Neanderthals, sexual dimorphism in limb bone size and robusticity appears to have reached recent human proportions.

(cité par Priscille Touraille)

Sexual dimorphism and human tooth size differences
Brace & Ryan
Journal of human evolution, 1980

Late in the Pleistocene the development of food processing techniques led to the reduction of both male and female dental dimensions. Dental sexual dimorphism, however, was maintained until the very end of the Pleistocene when the hunting of large game animals by crude techniques was replaced by a focus on great numbers of small game caught by more sophisticated means and by an increasing utilization of plant foods. The subsequent reduction in dimorphism represents the actions of the Probable Mutation Effect operating under conditions of relaxed selection. The conclusion offered is that the smallest degree of sexual dimorphism visible in the modern world is to be found among those populations that are separated by the greatest interval of time from precursors who depended for their survival on a Pleistocene big game hunting mode of subsistence.

(cité par Priscille Touraille)

Sexual dimorphism and cultural evolution in the Late Pleistocene and Holocene of Europe
David Frayer
Journal of human evolution, 1980

Dental, cranial and body size data are reviewed for European Upper Paleolithic, Mesolithic and Neolithic males and females. Over these three periods there is a substantial decrease in the level of sexual dimorphism. From separate analysis of trends occurring between males and females, it is shown that the major cause for this decrease in sexual dimorphism is gracilization of the males between the Upper Paleolithic and Mesolithic. Reduction in males is related to shifting technological patterns associated with hunting and changes in the types of animals hunted. Further reduction in sexual dimorphism between the Mesolithic and Neolithic and from the Neolithic to modern European populations is shown to be more closely tied to changes occurring among females. Analysis of changing patterns of sexual dimorphism in Late Pleistocene and Holocene populations of Europe suggests an interrelationship between cultural and biological evolution.

(cité par Priscille Touraille)

Differences between ethnic groups in sex dimorphism of adult height
Phyllis B. Eveleth
Annals of human biology, 1974

An analysis has been made of sex dimorphism in adult height using data from 58 Negroid, 76 European, and 67 Amerindian populations. Regression analyses were carried out on the sex difference and sex average of male and female stature means. The greatest sex dimorphism was found in Amerindians and the least in Negroid populations. Data from 36 Asiatic and 27 New Guinea populations have also been considered. It seems that sex dimorphism in adult height has a strong genetic component, making it inappropriate as a measure by which to judge the health and nutritional status of a population.

Divers visuels non issus de publications scientifiques


Différences physiques entre hommes et femmes

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