Sexual selection is a likely driving force for many examples of sexual dimorphism, particularly the weaponry and display traits that Darwin was interested in.
From an evolutionary standpoint, sex differences in disease can be seen as a subset of the more general phenomenon of sexual dimorphism of quantitative traits, including important life-history traits such as ageing and longevity [ 9 ]. How can males and females differ in so many ways and yet have a common genetic code?
Biomedical scientists have traditionally ignored the importance of phenotypic differences between males and females [ 1 ], although this is changing [ 2 ].
A review by Ober et al. Identifying specific cases of how males and females differ biologically is important therapeutically, but in order for biologists and physicians to gain a full understanding, it is necessary to appreciate how these differences came about [ 17 The evolution of the iasc into.
The mechanisms by which traits become sexually dimorphic, whether via sexual or natural selection, are still not fully resolved, although evolutionary models have been proposed based on sex-specific differences in selection and changes to the genetic architecture [ 12 ].
It is the ultimate causes and consequences of sexual dimorphism that I explore in this review, with the emphasis on human physiological and disease phenotypes. The effect of sex on disease can be manifest in many ways, including the presentation of the disease and its associated symptoms, the prevalence or age of onset.
Taking an evolutionary view on sex differences in disease provides an opportunity for greater understanding of mechanisms of disease and as such provides a clear motivation for clinicians to explore how therapies may be tailored to the individual in a sex-dependent way.
The aim is to provide a researcher working at the front line of human physiology and disease with a clearer understanding of how sex differences evolve and to explore some of the ways in which sex differences can create novel selective pressures, generating further evolutionary change.
I also discuss how sex differences in themselves can generate new risk factors for disease, in effect becoming a new environmental factor, as well as briefly reviewing more general evidence for sexually antagonistic selection and genetic variation within humans. Received Nov 21; Accepted Feb Essentially, differences in selection experienced by the two sexes are rooted in anisogamy unequal gamete size.
This as most fundamental of all sexual dimorphisms sets the stage for unequal investment by the two sexes in reproduction. This article has been cited by other articles in PMC. In this review, I outline current ideas about the evolutionary origins of sex differences in phenotypes, with a particular focus on how sex differences in disease can arise.
The evolution of sexual dimorphism Evolutionary biologists have long wondered why males and females are different. Traditionally, the modifying action of hormones has been offered as a solution to this paradox, but experiments disentangling the effects of hormones and sex-chromosomes have shown that this cannot be the sole explanation.
Evolutionary theory can provide useful insights into the origins of sex differences, either as adaptations in their own right in the case of physiological differences or in explaining why pathogenic phenotypes persist in a population [ 78 ].
Female reproductive success is limited by resource availability and acquisition, whereas male reproductive success is limited by access to mates and the number of fertilizations and may therefore be more variable. Sexual dimorphism, Sex-specific genetic architecture, Sex-chromosomes, Evolutionary medicine, Darwinian medicine, Sexual selection, Natural selection, Personalized medicine, Gender medicine Review Introduction In the inaugural article of Biology of Sex Differences [ 1 ], Arnold outlined the main motivations for why the existence of separate sexes is an important factor to consider when investigating human disease, the key point is that sex differences in human physiology exist and that they matter, both in terms of determining disease phenotypes and also for shaping more effective therapies.
The NIH, for example, recently announced it will be developing its policies to pay attention to sex differences in preclinical research [ 3 ], which is likely to result in considerable benefits should prospective gender-specific therapies be implemented [ 4 ].
But for other traits not used in male-male competition or mate choice, the explanation is less obvious. From a genetic point of view, this is paradoxical, since the vast majority of genetic material is shared between the sexes.
These include rates of disease incidence, symptoms and age of onset.
These differences between the sexes can be seen as a subset of the more general phenomenon of sexual dimorphism of quantitative phenotypes.
The skewed distribution in male reproductive success depends to a large extent on traits such as size of ornaments or weapons or overall body size [ 11 ]. Bateman who first studied them [ 13 ] —these show how fitness changes for each sex in terms of reproductive output as a function of number of matings.
Abstract It is now becoming widely recognized that there are important sex differences in disease.Abstract. ABSTRACT: In this article, I undertake to review the major developments and turningpoints in the evolution of the IASC, followed by the evolution of the IASB.
THE ACCOUNTING REVIEW American Accounting Association Vol. 87, No. 3 DOI: /accr pp. – The Evolution of the IASC into the IASB, and the Challenges it Faces Stephen A. Zeff Rice University ABSTRACT: In this article, I undertake to review the major developments and turning-points in the evolution of the.
iASC Inter-Agency Standing Committee v HPG Working Paper HPG workinG PAPEr of operational and organisational change and the evolution of new norms.
By shedding light on the factors that A history of the humanitarian system.
The evolution of sex differences in disease. Edward H Morrow. Author information Article notes Evolutionary theory can provide useful insights into the origins of sex differences, IASC is only realized when the intersexual genetic correlation for the trait.
The Evolution of the IASC into the IASB, and the Challenges it Faces Stephen A. Zeff Rice University ABSTRACT: In this article, I undertake to review the major developments and turningpoints in the evolution of the IASC, followed by the evolution of the IASB.
evolution of the IASB insurance contract project, this paper has looked into (i) what the IASB aims to achieve in this project and (ii) where the fundamental problem lies as to the situation where the project is.Download