Sexual selection
hideSexual selection is the theory proposed by Charles Darwin that states that certain evolutionary traits can be explained by intraspecific competition. Darwin defined sexual selection as the effects of the "struggle between the individuals of one sex, generally the males, for the possession of the other sex". Biologists today distinguish between "male to male combat" (it is usually males who fight each other), "mate choice" (usually female choice of male mates) and sexual conflict. Traits selected by male combat are called secondary sexual characteristics (including horns, antlers, etc.) and sometimes referred to as "weapons"; and traits selected by mate choice are called "ornaments". Much attention has been given to cryptic female choice, a phenomenon in internally fertilising animals such as mammals and birds, where a female will get rid of a male's sperm without his knowledge. The equivalent in male-to-male combat is sperm competition.
Direct competition between members of one sex (usually males) for mates is also classified as intrasexual selection, while mate choice is known as intersexual selection.
Females often prefer to mate with males with external ornaments—exaggerated features of morphology. These can plausibly arise because an arbitrary female preference for some aspect of male morphology initially increased by genetic drift, creating, in due course, selection for males with the appropriate ornament. This is known as the sexy son hypothesis. Alternatively, genes that enable males to develop impressive ornaments or fighting ability may simply show off greater disease resistance or a more efficient metabolism—features that also benefit females. This idea is known as the good genes hypothesis.
For more information about Sexual selection, read the full article at
Wikipedia.
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News tagged with mate choice
Ecological speciation by sexual selection on good genes: Is speciation adaptive?
Nov 26, 2009 |
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Darwin suggested that the action of natural selection can produce new species, but 150 years after the publication of his famous book, 'On the Origin of Species', debate still continues on the mechanisms of speciation. New ...
Are female mountain goats sexually conflicted over size of mate?
Nov 17, 2009 |
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Mountain goats are no exception to the general rule among mammals that larger males sire more and healthier offspring. But University of Alberta researcher David Coltman has found a genetic quirk that might make female mountain ...
Unnatural selection: Birth control pills may alter choice of partners
Oct 07, 2009 |
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There is no doubt that modern contraception has enabled women to have unprecedented control over their own fertility. However, is it possible that the use of oral contraceptives is interfering with a woman's ability to choose, ...
Fish go mad for ginger gene
Sep 28, 2009 |
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There may be plenty of fish in the sea but the medaka knows what it likes. A new study published in the open access journal BMC Biology shows how a single gene mutation that turns Japanese Killifish a drab ...
Disease threat may change how frogs mate
Jul 27, 2009 |
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Dr Amber Teacher, studying a post-doctorate at Royal Holloway, University of London, has discovered evidence that a disease may be causing a behavioural change in frogs. The research, published in the August edition of Molecular Ec ...
Study shows animal mating choices more complex than once thought
Jun 08, 2009 |
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When female tiger salamanders choose a mate, it turns out that size does matter - tail size that is - and that's not the only factor they weigh.
Opposites attract -- how genetics influences humans to choose their mates
May 25, 2009 |
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New light has been thrown on how humans choose their partners, a scientist will tell the annual conference of the European Society of Human Genetics today. Professor Maria da Graça Bicalho, head of the Immunogenetics and ...
Female mammals follow their noses to the right mates
Mar 17, 2009 |
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Female birds often choose their mates based on fancy feathers. Female mammals, on the other hand, may be more likely to follow their noses to the right mate. That's one conclusion of Cambridge zoologist Tim Clutton-Brock ...
It's in his smell
Mar 03, 2009 |
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A female moth selects a mate based on the scent of his pheromones. An analysis of the pheromones used by the European Corn Borer (ECB, Ostrinia nubilalis), featured in the open access journal BMC Biology, ...
Mate selection more biologically determined in some human populations
Biology /
Sep 12, 2008 |
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Some human populations may rely on biological factors in addition to social factors when selecting a mate. In a recent study, published September 12 in the open-access journal PLoS Genetics, scientists in China, France, and th ...
Male fish deceive rivals about their top mate choice
Biology /
Jul 31, 2008 |
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When competitors are around, male Atlantic mollies try to hide their top mate choice, reveals a new study published online on July 31st in Current Biology.
