Experimental evolution reveals trade
... investment. However, like all Lepidoptera, male P. interpunctella make a substantial reproductive investment at each mating— approximately 4 per cent of the male’s body mass [20]. It may be that the magnitude of male investment in ejaculate provisions transferred to females is sufficient to alter th ...
... investment. However, like all Lepidoptera, male P. interpunctella make a substantial reproductive investment at each mating— approximately 4 per cent of the male’s body mass [20]. It may be that the magnitude of male investment in ejaculate provisions transferred to females is sufficient to alter th ...
Does courtship behavior contribute to species
... isolating mechanisms. This is especially true in dense populations where a substantial number of mating interactions may be initiated without female phonotaxis to calling song, i.e., noncalling satellite and/or silent mate searching strategies are more effective at high density (Cade and Cade, 1992; ...
... isolating mechanisms. This is especially true in dense populations where a substantial number of mating interactions may be initiated without female phonotaxis to calling song, i.e., noncalling satellite and/or silent mate searching strategies are more effective at high density (Cade and Cade, 1992; ...
anita_repro_assignment_1
... achieve vaginal penetration and the inability to maintain this degree of penile rigidity until ejaculation. Penile diseases such as congenital malformation, peyronie’s disease, priapism, phimosis and rarely cold abscess may interfere with erectile function. There are two classification that have bee ...
... achieve vaginal penetration and the inability to maintain this degree of penile rigidity until ejaculation. Penile diseases such as congenital malformation, peyronie’s disease, priapism, phimosis and rarely cold abscess may interfere with erectile function. There are two classification that have bee ...
mate choice and its evolutionary consequences
... The ability to recognise potential mates and choose the best possible partner for reproduction is of fundamental importance for most animal species. This thesis presents studies of mate choice in marine snails of the genus Littorina, where male precopulatory mate choice seems to be more predominant ...
... The ability to recognise potential mates and choose the best possible partner for reproduction is of fundamental importance for most animal species. This thesis presents studies of mate choice in marine snails of the genus Littorina, where male precopulatory mate choice seems to be more predominant ...
Mate Choice, Sexual Conflict, and Evolution of Senescence
... on to their offspring. Thus, if a female can choose among males based on age, by choosing to mate with an older male, she is more likely to pass on high-quality viability genes to her offspring. Theoreticians have examined the conditions under which preference for old mates can evolve (Beck and Powe ...
... on to their offspring. Thus, if a female can choose among males based on age, by choosing to mate with an older male, she is more likely to pass on high-quality viability genes to her offspring. Theoreticians have examined the conditions under which preference for old mates can evolve (Beck and Powe ...
Social preferences based on sexual attractiveness: a female
... days each month just after parturition [18], at which time they emit chemical cues that attract males and stimulate male sexual activity [19]. For the remainder of the time, females are generally not receptive to mating attempts, although insemination at this time can lead to successful fertilizatio ...
... days each month just after parturition [18], at which time they emit chemical cues that attract males and stimulate male sexual activity [19]. For the remainder of the time, females are generally not receptive to mating attempts, although insemination at this time can lead to successful fertilizatio ...
Sexual selection on forelimb muscles of western grey kangaroos
... Both sexes of the larger kangaroos and wallabies (Macropodidae) have similar morphology but males often have extremely well-developed musculature of the arms and upper body. Can this difference in degree of development be explained in terms of sexual selection? The larger kangaroos and wallabies are ...
... Both sexes of the larger kangaroos and wallabies (Macropodidae) have similar morphology but males often have extremely well-developed musculature of the arms and upper body. Can this difference in degree of development be explained in terms of sexual selection? The larger kangaroos and wallabies are ...
- White Rose Research Online
... paternity. Delayed sperm ejection by a female after a second mating results in biased paternity in favour of the second male compared to individuals with a shorter sperm retention time. Thus, active regulation of the timing of sperm ejection could provide a mechanism by which females select sperm fr ...
... paternity. Delayed sperm ejection by a female after a second mating results in biased paternity in favour of the second male compared to individuals with a shorter sperm retention time. Thus, active regulation of the timing of sperm ejection could provide a mechanism by which females select sperm fr ...
Courtship role reversal and deceptive signals in the
... copulations for nuptial prey gifts. Females compete for male gifts within leks that are organized for a brief period each evening before dark. Before hovering within leks, females swallow air, inflating expandable pouches on the pleural margins of the abdomen. The result is a large saucer-like abdom ...
... copulations for nuptial prey gifts. Females compete for male gifts within leks that are organized for a brief period each evening before dark. Before hovering within leks, females swallow air, inflating expandable pouches on the pleural margins of the abdomen. The result is a large saucer-like abdom ...
Sex roles and sexual selection
... found in his studies of Drosophila melanogaster that multiple copulations led to a greater increase in the number of offspring produced in males than in females. Hence, he concluded that there is a greater advantage for males in copulating with several partners than there is for females, leading to ...
... found in his studies of Drosophila melanogaster that multiple copulations led to a greater increase in the number of offspring produced in males than in females. Hence, he concluded that there is a greater advantage for males in copulating with several partners than there is for females, leading to ...
Dusting Behavior - Digital Commons @ OWU
... related to sex and body size (Loizi et al. 2009 and Shannon et al. 2008). For example, post-pubescent and adult African elephant males are more likely than females to engage in chemosensory behaviors that could indicate female reproductive receptivity, including investigation of urine and feces. Whi ...
... related to sex and body size (Loizi et al. 2009 and Shannon et al. 2008). For example, post-pubescent and adult African elephant males are more likely than females to engage in chemosensory behaviors that could indicate female reproductive receptivity, including investigation of urine and feces. Whi ...
Summary of - DrMillsLMU
... adornments, whether to enhance sexual attractiveness or intimidate competitive males, have been poorly studied among primates. This review focuses on the relationships between occurrences of sexually dimorphic visual traits in male anthropoids (i.e., monkeys, apes, and human beings) and the types of ...
... adornments, whether to enhance sexual attractiveness or intimidate competitive males, have been poorly studied among primates. This review focuses on the relationships between occurrences of sexually dimorphic visual traits in male anthropoids (i.e., monkeys, apes, and human beings) and the types of ...
Crab-eating Raccoon
... and September. Both sexes are mature after one year but usually only older males breed as younger males cannot compete. It was recorded that 60% of wild and captive females mate as juveniles with litters being produced at 1 year old (Chapman and Feldhamer, 1983). Captive males may also mate and fath ...
... and September. Both sexes are mature after one year but usually only older males breed as younger males cannot compete. It was recorded that 60% of wild and captive females mate as juveniles with litters being produced at 1 year old (Chapman and Feldhamer, 1983). Captive males may also mate and fath ...
Cat Behavior and Training - Cat Neutering and Behavior
... Millions of cats are destroyed across North America each year because there are far more cats born than homes available. A single male cat can father many litters so that neutering of intact males is essential for population control. Although sexual desire will be greatly reduced by castration, some ...
... Millions of cats are destroyed across North America each year because there are far more cats born than homes available. A single male cat can father many litters so that neutering of intact males is essential for population control. Although sexual desire will be greatly reduced by castration, some ...
Sexual Selection - Evolutionary Biology
... • intersexual selection (generally seen as female choice) • ‘whilst in the other the struggle is likewise between the individuals of the same sex, in order to excite or charm those of the opposite sex, generally the females, which no longer remain passive, but select the more agreeable partners’ ...
... • intersexual selection (generally seen as female choice) • ‘whilst in the other the struggle is likewise between the individuals of the same sex, in order to excite or charm those of the opposite sex, generally the females, which no longer remain passive, but select the more agreeable partners’ ...
Eating Disorders and Males - John Hunter Hospital School
... The information in this article is by no means intended as a substitute for medical advice from a qualified health practitioner. It does not recommend any one treatment, therapy or medication. Please seek medical advice as different medications suit different individuals. ...
... The information in this article is by no means intended as a substitute for medical advice from a qualified health practitioner. It does not recommend any one treatment, therapy or medication. Please seek medical advice as different medications suit different individuals. ...
Allee effect, sexual selection and demographic stochasticity
... n (as expected), but that the convergence was rather slow. For n=50, we had p(n):90%, and for n= 10, p(n) :75%. In this first case, there was no assumption on the success of the matings. Incompatibility between phenotypes was then considered, assuming two incompatible phenotypes in equal average pro ...
... n (as expected), but that the convergence was rather slow. For n=50, we had p(n):90%, and for n= 10, p(n) :75%. In this first case, there was no assumption on the success of the matings. Incompatibility between phenotypes was then considered, assuming two incompatible phenotypes in equal average pro ...
Sexually selected females in the monogamous Western Australian
... We do not know the mechanism of the observed sexual selection on females, i.e. whether it is generated by intrasexual competition among females for males or by intersexual mate choice as a consequence of male preference for large females. The answer to this question will call for future, detailed be ...
... We do not know the mechanism of the observed sexual selection on females, i.e. whether it is generated by intrasexual competition among females for males or by intersexual mate choice as a consequence of male preference for large females. The answer to this question will call for future, detailed be ...
Sexual Selection Revisited — Towards a Gender- Neutral
... females has received less attention. Later theoretical work has revealed that Bateman’s result could be explained by both sexes mating randomly (e.g. no mate choice or male competition) (see Gowaty and Hubbell, 2005). Thus, differential variance in reproductive success between the sexes cannot alone ...
... females has received less attention. Later theoretical work has revealed that Bateman’s result could be explained by both sexes mating randomly (e.g. no mate choice or male competition) (see Gowaty and Hubbell, 2005). Thus, differential variance in reproductive success between the sexes cannot alone ...
sexually transmitted disease and the evolution of mating
... pathogens or parasites, females should be able to use sexual signals as indicators of genetic quality. The Hamilton-Zuk hypothesis proposes that host-parasite coevolution maintains variation in heritable quality. More recently, much attention has been focused on the related immunocompetence-handicap ...
... pathogens or parasites, females should be able to use sexual signals as indicators of genetic quality. The Hamilton-Zuk hypothesis proposes that host-parasite coevolution maintains variation in heritable quality. More recently, much attention has been focused on the related immunocompetence-handicap ...
Rapid evolutionary change in a sexual signal
... the very same elements of a signal that are preferred by females and because of this sexual signals represent a compromise between natural and sexual selection (Zuk and Kolluru, 1998). Perhaps the best-known example of this comes from túngara frogs where both females and predatory fringe-lipped bat ...
... the very same elements of a signal that are preferred by females and because of this sexual signals represent a compromise between natural and sexual selection (Zuk and Kolluru, 1998). Perhaps the best-known example of this comes from túngara frogs where both females and predatory fringe-lipped bat ...
Chapter 11: Sex and Evolution
... such species. In particular, which gender has more variable mating success? What basic asymmetry of life is responsible for this phenomenon and why? Answer: Males typically have more variable mating success than females. Females cannot increase their reproductive success by mating with many males be ...
... such species. In particular, which gender has more variable mating success? What basic asymmetry of life is responsible for this phenomenon and why? Answer: Males typically have more variable mating success than females. Females cannot increase their reproductive success by mating with many males be ...
Microsatellite analysis of maternity and the mating system in the Gulf
... operating on females than on males constitutes the definitional basis of sex-role reversal in recent sociobiological theory (Vincent et al. 1992). This reversal is thought to result from a female biased operational sex ratio (OSR), such that more females than males are available to mate at any given ...
... operating on females than on males constitutes the definitional basis of sex-role reversal in recent sociobiological theory (Vincent et al. 1992). This reversal is thought to result from a female biased operational sex ratio (OSR), such that more females than males are available to mate at any given ...
Microsatellite analysis of maternity and the mating system Syngnathus scovelli
... operating on females than on males constitutes the definitional basis of sex-role reversal in recent sociobiological theory (Vincent et al. 1992). This reversal is thought to result from a female biased operational sex ratio (OSR), such that more females than males are available to mate at any given ...
... operating on females than on males constitutes the definitional basis of sex-role reversal in recent sociobiological theory (Vincent et al. 1992). This reversal is thought to result from a female biased operational sex ratio (OSR), such that more females than males are available to mate at any given ...
Bateman`s principles and human sex roles - synergy
... of offspring (reproductive success [RS]) than females; (ii) males showed greater variance in number of sexual partners (mating success [MS]) than females; and (iii) there was a stronger relationship between RS and MS among males than females (note, Bateman measured mating success as the number of pa ...
... of offspring (reproductive success [RS]) than females; (ii) males showed greater variance in number of sexual partners (mating success [MS]) than females; and (iii) there was a stronger relationship between RS and MS among males than females (note, Bateman measured mating success as the number of pa ...