Do you have low testosterone? Why does it
... extension medicine for the use of testosterone in anti-aging therapies. The literature suggests that testosterone may have a positive effect on mood and depression. High androgen levels are associated with menstrual cycle irregularities in both clinical populations and healthy women. Testosterone ma ...
... extension medicine for the use of testosterone in anti-aging therapies. The literature suggests that testosterone may have a positive effect on mood and depression. High androgen levels are associated with menstrual cycle irregularities in both clinical populations and healthy women. Testosterone ma ...
Universal Sex Differences in the Desire for Sexual Variety: Tests
... Although SST views both sexes as having long-term and shortterm strategies within their repertoire, men and women are predicted to differ fundamentally in certain respects. In long-term mating, for example, the sexes are predicted to differ in their mate preferences. Men are hypothesized to place a ...
... Although SST views both sexes as having long-term and shortterm strategies within their repertoire, men and women are predicted to differ fundamentally in certain respects. In long-term mating, for example, the sexes are predicted to differ in their mate preferences. Men are hypothesized to place a ...
Sexual Selection Favors Female‐Biased Sex Ratios: The Balance
... hypothesis. Some authors have called for a “greater integration of empirical and theoretical work on the TW hypothesis” (Carranza 2002, p. F3; see also Clutton-Brock 1991). However, others have suggested that the simplicity and extendability of the TW model is powerful because it can be applied “to ...
... hypothesis. Some authors have called for a “greater integration of empirical and theoretical work on the TW hypothesis” (Carranza 2002, p. F3; see also Clutton-Brock 1991). However, others have suggested that the simplicity and extendability of the TW model is powerful because it can be applied “to ...
Sexual Dimorphism in Human Hip Bone
... The four main features of biological identity are sex, age, stature and ethnic background. A reliable estimation of sex from the skeleton by using various criteria is important while dealing with undocumented skeletal material. Skeletal characteristics vary among populations; therefore each populati ...
... The four main features of biological identity are sex, age, stature and ethnic background. A reliable estimation of sex from the skeleton by using various criteria is important while dealing with undocumented skeletal material. Skeletal characteristics vary among populations; therefore each populati ...
Testing evolutionary hypotheses about human biological adaptation
... impact on the future reproductive success of males than of females, then the optimal sex ratio of offspring could be dependent on the resources available to the mother. In most polygynous species, whilst average reproductive success of males and females is equal, variation in male reproductive succe ...
... impact on the future reproductive success of males than of females, then the optimal sex ratio of offspring could be dependent on the resources available to the mother. In most polygynous species, whilst average reproductive success of males and females is equal, variation in male reproductive succe ...
Journal of Evolutionary Biology 26
... selection is important in driving adaptive divergence. Indeed, sperm competitive ability in Drosophila has been directly linked to polymorphism in certain male reproductive genes (Fiumera et al., 2005). Presumably, increasing competition between males for mating increases the intensity of sperm comp ...
... selection is important in driving adaptive divergence. Indeed, sperm competitive ability in Drosophila has been directly linked to polymorphism in certain male reproductive genes (Fiumera et al., 2005). Presumably, increasing competition between males for mating increases the intensity of sperm comp ...
Evolutionary Psychology - College of Agriculture and Life Sciences
... by the way that similar species were grouped together geographically, and by their apparent fit to local ecological conditions. Although the idea of biological evolution had been around for some time, what had been missing was an explanation of how evolution occurred—that is, what had been missing w ...
... by the way that similar species were grouped together geographically, and by their apparent fit to local ecological conditions. Although the idea of biological evolution had been around for some time, what had been missing was an explanation of how evolution occurred—that is, what had been missing w ...
Intralocus sexual conflict in hermaphroditic animals
... important contributor to mating rate) may be correlated and antagonistically selected between ...
... important contributor to mating rate) may be correlated and antagonistically selected between ...
Intralocus sexual conflict in hermaphroditic animals
... important contributor to mating rate) may be correlated and antagonistically selected between ...
... important contributor to mating rate) may be correlated and antagonistically selected between ...
A Guide to Sexual Selection Theory
... Sexual selection is the process by which individuals compete for access to mates and fertilization opportunities (Andersson 1994, Jones & Ratterman 2009). Darwin (1871) developed the concept of sexual selection to explain the evolution of exaggerated and flamboyant characters such as calls, odors, or ...
... Sexual selection is the process by which individuals compete for access to mates and fertilization opportunities (Andersson 1994, Jones & Ratterman 2009). Darwin (1871) developed the concept of sexual selection to explain the evolution of exaggerated and flamboyant characters such as calls, odors, or ...
Aerial performance of stalk-eyed ¯ies that differ in eye span
... mass. C. whitei males had longer wings, heavier thoraxes, and lighter abdomens in relation to body mass than did female C. whitei or C. quinqueguttata of either sex. Three-dimensional tracking of ¯ight paths showed that path velocity and the horizontal component of velocity did not dier according t ...
... mass. C. whitei males had longer wings, heavier thoraxes, and lighter abdomens in relation to body mass than did female C. whitei or C. quinqueguttata of either sex. Three-dimensional tracking of ¯ight paths showed that path velocity and the horizontal component of velocity did not dier according t ...
The scope and strength of sexspecific selection in genome evolution
... from mammals and birds suggests that the degree of sex-biased expression is lowest in the brain (Yang et al., 2006; Mank et al., 2008a; Reinius et al., 2008). However, these studies tend to examine the brain as a whole and thus, a more detailed examination of specific areas of the brain may reveal a ...
... from mammals and birds suggests that the degree of sex-biased expression is lowest in the brain (Yang et al., 2006; Mank et al., 2008a; Reinius et al., 2008). However, these studies tend to examine the brain as a whole and thus, a more detailed examination of specific areas of the brain may reveal a ...
Polyandry as a mediator of sexual selection before and after mating
... for both males and females [19] (cf. figure 2c). There are many costs of mating in general, and with multiple partners in particular [20,21]. For example, mate searching is often associated with time, energy and increased predation risk, as is competition for mates, courtship and mating activities [ ...
... for both males and females [19] (cf. figure 2c). There are many costs of mating in general, and with multiple partners in particular [20,21]. For example, mate searching is often associated with time, energy and increased predation risk, as is competition for mates, courtship and mating activities [ ...
FEMALE MATE-CHOICE BEHAVIOR AND SYMPATRIC SPECIATION
... individuals are either asexual or mate choice is determined by very simple rules. Females, for example, may be assumed either to compare their phenotype to that of a potential mate, preferring to mate with similar males (phenotype matching), or to possess preference genes that determine which male p ...
... individuals are either asexual or mate choice is determined by very simple rules. Females, for example, may be assumed either to compare their phenotype to that of a potential mate, preferring to mate with similar males (phenotype matching), or to possess preference genes that determine which male p ...
variation in mate choice and mating preferences: a review of causes
... unchanged. At present, evidence for stability is based on data that the mean preference function at the population level is unchanged (e.g. Ryan et al., ). However, selection on female choosiness could lead to very different patterns of mate choice. For example, two species could both have audit ...
... unchanged. At present, evidence for stability is based on data that the mean preference function at the population level is unchanged (e.g. Ryan et al., ). However, selection on female choosiness could lead to very different patterns of mate choice. For example, two species could both have audit ...
Testosterone`s Effects on Anxiety
... Animal Studies (in male rats) showing androgen receptor (AR) involvement in T’s action on hippocampus: • Gonadectomized (GDX) rats showed increased anxiety • DHT replacement to GDX rats showed decreased anxiety • AR blockade of intact or DHT-replaced male rats with AR antagonist (Flutamide) ↑ anxiet ...
... Animal Studies (in male rats) showing androgen receptor (AR) involvement in T’s action on hippocampus: • Gonadectomized (GDX) rats showed increased anxiety • DHT replacement to GDX rats showed decreased anxiety • AR blockade of intact or DHT-replaced male rats with AR antagonist (Flutamide) ↑ anxiet ...
Possible ecological risks of transgenic organism release when
... lthough production of transgenic organisms offers great agricultural potential, introduction of genetically modified organisms into natural populations could result in ecological hazards, such as species extinction (1–3). Such risk has been suggested to pose little environmental threat because trans ...
... lthough production of transgenic organisms offers great agricultural potential, introduction of genetically modified organisms into natural populations could result in ecological hazards, such as species extinction (1–3). Such risk has been suggested to pose little environmental threat because trans ...
sex-specific growth in the european sha g
... (Amundsen & Stockland 1988 ; Velando 1997) . (Velando 1997) . Fifty-six nesting sites were tagBecause this species is clearly dimorphic in size ged beginning in 1994 and visited periodically (males are 22% heavier than females during the thereafter. The fieldwork was carried out in colobreeding seas ...
... (Amundsen & Stockland 1988 ; Velando 1997) . (Velando 1997) . Fifty-six nesting sites were tagBecause this species is clearly dimorphic in size ged beginning in 1994 and visited periodically (males are 22% heavier than females during the thereafter. The fieldwork was carried out in colobreeding seas ...
The use of multiple cues in mate choice
... and be maintained due to other selection pressures than selection for communication. For example, body constitution and running speed may be under survival selection but simultaneously be used as indicators of fitness. However, often the traits have been modified for communication, or serve a function ...
... and be maintained due to other selection pressures than selection for communication. For example, body constitution and running speed may be under survival selection but simultaneously be used as indicators of fitness. However, often the traits have been modified for communication, or serve a function ...
Models of sexual and asexual coexistence in aphids based on
... Biological data on the genetic determination oj’ lijk-cycle in rrphids The genetic basis of the different types of life-cycle has been extensively studied in two aphid species, A4yzus persiue (Blackman, 1972) and Rhopalosiphum padi (Simon, 1991; Simon et al., 1994). A single locus appears to determi ...
... Biological data on the genetic determination oj’ lijk-cycle in rrphids The genetic basis of the different types of life-cycle has been extensively studied in two aphid species, A4yzus persiue (Blackman, 1972) and Rhopalosiphum padi (Simon, 1991; Simon et al., 1994). A single locus appears to determi ...
The Role of Coloration in Mate Choice and Sexual
... (GEIs) in the expression of the signal trait (Hunt et al., 2004; Kokko and Heubel, 2008). Simply, a GEI refers to a developmental outcome in which the phenotype that results from a particular genotype is a function of the environment under which the organism developed (or in which the gene(s) of int ...
... (GEIs) in the expression of the signal trait (Hunt et al., 2004; Kokko and Heubel, 2008). Simply, a GEI refers to a developmental outcome in which the phenotype that results from a particular genotype is a function of the environment under which the organism developed (or in which the gene(s) of int ...
Eye Tracking of Men`s Preferences for Female Breast Size and
... A total of 37 heterosexual men of European descent, ranging in age from 22 to 47 years (M = 30.05 years; SD = 6.21), were recruited opportunistically from the staff and post-graduate student body at Victoria University. Ten of these men were married. Participants were given individual verbal briefin ...
... A total of 37 heterosexual men of European descent, ranging in age from 22 to 47 years (M = 30.05 years; SD = 6.21), were recruited opportunistically from the staff and post-graduate student body at Victoria University. Ten of these men were married. Participants were given individual verbal briefin ...
Genetics of postzygotic isolation and Haldane`s rule in
... of species 2 hybridizes with a male of species 1, the male offspring will have a2b1b2 genotype, whereas female offspring will have a1a2b1b2 genotype. For the female genotype to show hybrid incompatibilities still both a2 and b2 have to be dominant, whereas for the male genotype to show incompatibili ...
... of species 2 hybridizes with a male of species 1, the male offspring will have a2b1b2 genotype, whereas female offspring will have a1a2b1b2 genotype. For the female genotype to show hybrid incompatibilities still both a2 and b2 have to be dominant, whereas for the male genotype to show incompatibili ...
Evolutionary Psychology and Feminism
... mechanisms, information processing devices housed in the brain, in conjunction with the external and internal inputs—social, cultural, ecological, physiological—that interact with them to produce manifest behavior; (2) Evolution by selection is the only known causal process capable of creating such ...
... mechanisms, information processing devices housed in the brain, in conjunction with the external and internal inputs—social, cultural, ecological, physiological—that interact with them to produce manifest behavior; (2) Evolution by selection is the only known causal process capable of creating such ...
sexual dimorphism of clavicle in south indian population
... are established for all skeletal elements and the proportions are expressed as indices in 38 th edition of Grays Anatomy [4]. In 1951, Oliver found that the left clavicle to be longer than the MATERIALS AND METHODS right in French people [5]. The present study also This cross sectional study has bee ...
... are established for all skeletal elements and the proportions are expressed as indices in 38 th edition of Grays Anatomy [4]. In 1951, Oliver found that the left clavicle to be longer than the MATERIALS AND METHODS right in French people [5]. The present study also This cross sectional study has bee ...