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Sex in Advertising: A Closer Look - Paul Long Home Page
Sex in Advertising: A Closer Look - Paul Long Home Page

... II. The History of Sex in Advertising The use of sexual information in mediated promotional messages has maintained a foothold in the media since advertising’s beginning. Sex in advertising began when items such as wood carvings, posters, and signs that depicted attractive and scantily-clad women a ...
Correcting some common misrepresentations of evolution in
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Flexbook ()
Flexbook ()

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Polyandry as a mediator of sexual selection before and after mating
Polyandry as a mediator of sexual selection before and after mating

... Figure 1. Operational sex ratio (OSR) is a central concept for understanding variation in mating competition and sexual selection within and between species. OSR is the ratio (m : f ) or proportion (m/m þ f ) of males and females that are ready to mate in a population at any one time [4,9]. In many ...
Genetic Variation Underlying Sexual Behavior and Reproduction
Genetic Variation Underlying Sexual Behavior and Reproduction

... in males. Females often appear to choose mates, however, suggesting genetic variation in males which is important to females. Evidence is reviewed on allelic substitutions, karyotypic variation, and especially the heritable variation of continuous traits involved in sexual behavior and reproduction. ...
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saes1ext_lect_outline_ch12

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SEXUAL SELECTION AND THE DESCENT OF MAN 1871-1971
SEXUAL SELECTION AND THE DESCENT OF MAN 1871-1971

... than once or twice. As shown by genetic markers in the offspring, males showed an almost linear increase in reproductive success with increased copulations. (A corollary of this finding is that males tended not to mate with the same female twice.) Although these results were obtained in the laborato ...
Parental Investment and Sexual Selection
Parental Investment and Sexual Selection

... than once or twice. As shown by genetic markers in the offspring, males showed an almost linear increase in reproductive success with increased copulations. (A corollary of this finding is that males tended not to mate with the same female twice.) Although these results were obtained in the laborato ...
Sexual Dysfunction Is Common in the Morbidly Obese Male and
Sexual Dysfunction Is Common in the Morbidly Obese Male and

... obesity is the mainstay of therapy. Although bariatric surgery certainly has risks, it has been shown to improve life expectancy, medical comorbidities, and quality of life. The national mortality rate after bariatric surgery is approximately 0.2%.24 Although 30% of the eligible obese population is ...
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EXAM 4-Spring 2005con respuestas.doc

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review
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... 33. Explain how geologic processes can fragment populations and lead to speciation. 34. Explain how sympatric speciation can occur, noting examples in plants and animals. 35. Explain why polyploidy is important to modern agriculture. Explain how modern wheat evolved. 36. Explain how hybrid zones are ...
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Reproduction in Aspergillus fumigatus: sexuality

... genetic ‘hitchhiking’ and enables removal of deleterious genes [2,5]. The latter is a particular benefit over purely asexual species where mutations can accumulate and become fixed within populations (e.g. the concept of Muller’s ratchet) [3,5]. Indeed, it has been argued that the benefits of sex, e ...
Descent with Modification – A Darwinian View of Life
Descent with Modification – A Darwinian View of Life

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Charles Darwin-reserach-term1

... sailed in a ship called the Beagle. The Beagle was not a big ship, it was only about 28 metres long and had to be home to 74 people for the whole voyage. Darwin took with him a copy of the bible and books by Milton, Humboldt as well as a copy of Lyell's first volume on Principles Of Geology. He also ...
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Bulletin of the World Health Organization
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The Genetic Basis for Sex Differences in Human Behaviour: Role of
The Genetic Basis for Sex Differences in Human Behaviour: Role of

... XX embryo (Koopman et al. 1991), and that it has both the spatial and temporal expression consistent with its identity as the TDF (e.g. McLaren, 1998). The expression of SRY , in a normal male, stimulates the undifferentiated gonad, containing both Mullerian and Wolffian ducts, to develop into the t ...
IOSR Journal Of Humanities And Social Science (IOSR-JHSS)
IOSR Journal Of Humanities And Social Science (IOSR-JHSS)

... abandoned several main factors that influence self disclosure. Gender, race, ethnic background, and even age could greatly influence findings and may contribute to the rate at which the onion is “shed”. Altman and Taylor [1973] while addressing the subject of adolescents‟ cybersex, also argued that ...
ppt - eweb.furman.edu
ppt - eweb.furman.edu

... P1: All populations have the capacity to ‘over-reproduce’ P2: Resources are finite C: There will be a “struggle for existence”… most offspring born will die before reaching reproductive age. P3: Organisms in a population vary, and some of this variation is heritable C2: As a result of this variation ...
Télécharger le pdf
Télécharger le pdf

... we ever hope to fully appreciate the extraordinary subtlety of this most important biological principle; for much of it has been handed down from Darwin without serious reflection or re-examination. 3 Since this paper is a philosophical consideration of the doctrine of natural selection, we must exa ...
A New Concept. Geodakian V. A. Russian J. of Genetics, 1998, v
A New Concept. Geodakian V. A. Russian J. of Genetics, 1998, v

... According to Darwin's theory, the evolution of a system follows environmental alteration and proceeds as a trial-and-error process. Hence, it is more advantageous to test part of a system rather than the whole. For this, the system should be divided into two parts: the first, more valuable part shou ...
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Sexual selection



Sexual selection is a mode of natural selection where typically members of one gender choose mates of the other gender to mate with, called intersexual selection, and where females normally do the choosing, and competition between members of the same gender to sexually reproduce with members of the opposite sex, called intrasexual selection. These two forms of selection mean that some individuals have better reproductive success than others within a population either from being sexier or preferring sexier partners to produce offspring. For instance in the breeding season sexual selection in frogs occurs with the males first gathering at the water's edge and croaking. The females then arrive and choose the males with the deepest croaks and best territories. Generalizing, males benefit from frequent mating and monopolizing access to a group of fertile females. Females have a limited number of offspring they can have and they maximize the return on the energy they invest in reproduction.First articulated by Charles Darwin who described it as driving speciation and that many organisms had evolved features whose function was deleterious to their individual survival, and then developed by Ronald Fisher in the early 20th century. Sexual selection can lead typically males to extreme efforts to demonstrate their fitness to be chosen by females, producing secondary sexual characteristics, such as ornate bird tails like the peacock plumage, or the antlers of deer, or the manes of lions, caused by a positive feedback mechanism known as a Fisherian runaway, where the passing on of the desire for a trait in one sex is as important as having the trait in the other sex in producing the runaway effect. Although the sexy son hypothesis indicates that females would prefer male sons, Fisher's principle explains why the sex ratio is 1:1 almost without exception. Sexual selection is also found in plants and fungi.The maintenance of sexual reproduction in a highly competitive world has long been one of the major mysteries of biology given that asexual reproduction can reproduce much more quickly as 50% of offspring are not males, unable to produce offspring themselves. However, research published in 2015 indicates that sexual selection can explain the persistence of sexual reproduction.
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