February 2012
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The Power of Estrogen: Male Snakes Attract Other... →
h3ro-of-m1nd:
A new study has shown that boosting the estrogen levels of male garter snakes causes them to secrete the same pheromones that females use to attract suitors, and turned the males into just about the sexiest snake in the neighborhood — attracting dozens of other males eager to mate.
[Image: This female garter snake is entwined in a “mating ball,” being sought by numerous other...
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A Bug's (Sex) Life: Diving Beetles Offer... →
shychemist:
Diving beetles are voracious predators. Even small puddles of freshwater often host several different species. (Credit: D. Sikes)
Studies of diving beetles suggest sperm evolution may be driven by changes in female reproductive organs, challenging the paradigm of post-mating sexual selection being driven mostly by competition among sperm.
Studying female reproductive tracts and...
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Synalpheus brooksi, one of about six eusocial shrimp species in the genus of snapping shrimp Sylanpheus, lives in large social colonies and usually has several reproducing females in a sponge.
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January 2012
20 posts
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Y-Chromosome Variation in Hominids: Intraspecific... →
High intraspecific variation in copy number and position of the DAZ and CDY genes is seen only in the chimpanzee. We hypothesize that this is best explained by sperm competition that results in the variant DAZ and CDY haplotypes detected in this species. In contrast, bonobos, gorillas and orangutans—species that are not subject to sperm competition—showed no intraspecific variation...
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Shape - but Not Size - Codivergence between Male... →
Genitalia are among the fastest evolving morphological traits in arthropods. Among the many hypotheses aimed at explaining this observation, some explicitly or implicitly predict concomitant male and female changes of genital traits that interact during copulation (i.e., lock and key, sexual conflict, cryptic female choice and pleiotropy). Testing these hypotheses requires insights into whether...
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Molecular Mechanism Links Temperature With Sex... →
A study led by the CSIC’s Institute of Marine Sciences, in collaboration with researchers from the Centre for Genomic Regulation (CRG), has found the epigenetic mechanism that links temperature and gonadal sex in fish. High temperature increases DNA methylation of the gonadal aromatase promoter in female.
The environmental temperature has effects on sex determination. There are species,...
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December 2011
28 posts
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During mating rituals, male cuttlefish often showcase this “zebra” pattern.
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The cuckoo catfish tricks cichlids into raising its fry. The cichlid is a mouthbreeder—it carries and protects the fry in its mouth until they are big enough to fend for themselves. After a cichlid has laid eggs, the cuckoo catfish darts in and lays her eggs among the host eggs, and the cichlid later scoops up and incubates all the eggs. Cuckoo catfish eggs hatch before the host eggs, which...
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