http://www.physorg.com/ en-us Physorg.com internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (PhysOrg.com) -- With its flamboyantly decorated plumage, the peacock is a classic example of how males among many bird species are more visually eye-catching than their female partners. But new research, led by Columbia biologist Dustin Rubenstein, shows that, in some cases, females living in family groups are just as showy as males. The findings, which appear in the Dec. 10 issue of the journal Nature, shed new light on Darwin`s theory of sexual selection. http://www.physorg.com/news180104802.html Biology Tue, 15 Dec 2009 13:17:51 EST news180104802 (PhysOrg.com) -- Female birds in species that breed in groups can find themselves under pressure to sexually show off and evolve the same kinds of embellishments - like fanciful tail feathers or chest-puffing courtship dances - as males, according to new research in the latest issue of Nature (Dec. 10, 2009). http://www.physorg.com/news179586770.html Biology Wed, 09 Dec 2009 13:13:22 EST news179586770 Females can be too attractive to the opposite sex -- too attractive for their own good -- say biologists at UC Santa Barbara. They found that, among fruit flies, too much male attention directed toward attractive females leads to smaller families and, ultimately, to a reduced rate of population-wide adaptive evolution. http://www.physorg.com/news179502397.html Biology Tue, 08 Dec 2009 14:20:01 EST news179502397 "Why is it that men can be bastards and women must wear pearls and smile?" wrote author Lynn Hecht Schafran. The answer, according to an article in the Journal of Vision, may lie in our interpretation of facial expressions. http://www.physorg.com/news179170846.html Medicine & Health Fri, 04 Dec 2009 17:42:02 EST news179170846 The world's largest species of monkey 'chooses' mates with genes that are different from their own to guarantee healthy and strong offspring, according to a new research study. http://www.physorg.com/news178315092.html Biology Tue, 24 Nov 2009 19:59:12 EST news178315092 (PhysOrg.com) -- Males have more pronounced personalities than females across a range of species - from humans to house sparrows - according to new research. Consistent personality traits, such as aggression and daring, are also more important to females when looking for a mate than they are to males. Research from the University of Exeter draws together a range of studies to reveal the role that sexual selection plays in this disparity between males and females. http://www.physorg.com/news177760776.html Biology Wed, 18 Nov 2009 10:00:46 EST news177760776 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 goats think twice about their romantic partners. http://www.physorg.com/news177692981.html Biology Tue, 17 Nov 2009 15:20:02 EST news177692981 (PhysOrg.com) -- Female water striders often reject their most persistent and aggressive suitors and prefer the males who aren't so grabby, according to new research. Water striders are insects commonly seen skittering across the surface of streams. http://www.physorg.com/news176652474.html Biology Thu, 05 Nov 2009 14:08:45 EST news176652474 The great diversity of male sexual traits, ranging from peacock's elaborate train to formidable genitalia of male seed beetles, is the result of female choice. But why do females choose among males? In a new study published today in Current Biology, researchers from Uppsala University found no support for the theory that the female choice is connected to "good genes". http://www.physorg.com/news175439685.html Biology Thu, 22 Oct 2009 14:30:02 EST news175439685 The sperm of male fruit flies are coated with a chemical 'sex peptide' which inhibits the female's usual afternoon siesta and compels her into an intense period of foraging activity. http://www.physorg.com/news173512654.html Biology Wed, 30 Sep 2009 06:58:14 EST news173512654 (PhysOrg.com) -- Scientists have found new evidence to explain how female insects can influence the father of their offspring, even after mating with up to ten males. A team from the University of Exeter has found that female crickets are able to control the amount of sperm that they store from each mate to select the best father for their young. http://www.physorg.com/news171627059.html Biology Tue, 08 Sep 2009 11:11:41 EST news171627059 (PhysOrg.com) -- When it comes to potential mates, women may be as complicated as men claim they are, according to psychologists. http://www.physorg.com/news170331327.html Medicine & Health Mon, 24 Aug 2009 11:15:58 EST news170331327 (PhysOrg.com) -- How honest are males when using sexual displays to signal their eligibility to females? http://www.physorg.com/news170079585.html Biology Fri, 21 Aug 2009 13:20:25 EST news170079585 (PhysOrg.com) -- Attractive males release fewer sperm per mating to maximise their chances of producing offspring across a range of females, according to a new paper on the evolution of ejaculation strategies. The findings by researchers at UCL (University College London) and the University of Oxford suggest that, paradoxically, matings with attractive males may be less fertile than those with unattractive ones. http://www.physorg.com/news166354811.html Biology Thu, 09 Jul 2009 10:40:43 EST news166354811 Contrary to predictions, males of high genetic quality are not very successful when it comes to fertilizing eggs. A new study on seed beetles by Swedish and Danish scientists Göran Arnqvist and Trine Bilde shows that when a female mates with several males, the males of low genetic quality are the most successful in fertilizing eggs. The study is published in this week's issue of Science. http://www.physorg.com/news165158293.html Biology Thu, 25 Jun 2009 15:10:06 EST news165158293 Throughout the animal kingdom brilliant colors or elaborate behavioral displays serve as "advertisements" for attracting mates. But, what do the ads promise, and is there truth in advertizing? Researchers at Yale theorize that when males must provide care for the survival of their offspring, the males' signals will consistently be honest - and they may devote more of their energy to caring for their offspring than to being attractive. http://www.physorg.com/news164539008.html Biology Thu, 18 Jun 2009 10:18:28 EST news164539008 In order to increase their chances of reproductive success, male flies of the species Drosophila montana try to copulate for much longer than the females would like. Researchers writing in the open access journal BMC Evolutionary Biology have shown that females engaged in extended intercourse wait longer before they mate again, increasing the first fly's chances of fathering offspring. http://www.physorg.com/news163989479.html Biology Fri, 12 Jun 2009 07:50:01 EST news163989479 In a study published in PLoS ONE June 10, Chang Seok Han and Piotr Jablonski at Seoul National University, Korea, report that by evolving a morphological shield to protect their genitalia from males' forceful copulatory attempts, females of an Asian species of water strider seem to "win" the evolutionary arms race between the sexes. Instead, females only expose their genitalia for copulation after males produce a courtship "song" by tapping the water surface. http://www.physorg.com/news163938148.html Biology Thu, 11 Jun 2009 11:22:49 EST news163938148 Whether baby lizards will turn out to be male or female is a more complicated question than scientists would have ever guessed, according to a new report published online on June 4th in Current Biology. The study shows that for at least one lizard species, egg size matters. http://www.physorg.com/news163342512.html Biology Thu, 04 Jun 2009 13:56:04 EST news163342512 Even while their blood pressures are still normal, overweight male teens may have elevated levels of a hormone known to increase pressures as well as early signs of heart damage, researchers say. http://www.physorg.com/news163075850.html Medicine & Health Mon, 01 Jun 2009 11:51:13 EST news163075850 A new study led by the University of Leicester has demonstrated that consuming alcohol did not affect how men judged the age of women. This has important legal implications if alcohol is cited as a cause of impairing judgement in cases of unlawful sex with a minor. http://www.physorg.com/news159443558.html Medicine & Health Mon, 20 Apr 2009 10:52:59 EST news159443558 Deletions, duplications or rearrangements of genomic regions in the human genomes produce differences in gene copy numbers, referred to as copy number variations (CNV). Those variations account for a substantial portion of human genetic diversity, and in a few cases, have been associated with behavioural traits or increased susceptibility to disease. A study published today in the open access journal BMC Genetics, describes a CNV map of the African American genome, and compares frequencies of CNVs between African American and white American/European populations. http://www.physorg.com/news157105146.html Medicine & Health Tue, 24 Mar 2009 09:20:22 EST news157105146 Adults of many animal species play a crucial role in the social development of youngsters. A new study published March 18 in the online, peer-reviewed, open-access journal PLoS ONE, reveals that the ratio of adults to young plays a much more important role in social development than the mere presence of adults. http://www.physorg.com/news156541001.html Biology Tue, 17 Mar 2009 20:37:09 EST news156541001 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 and Harvard researcher Katherine McAuliffe, whose review of evidence for female mate choice is published in the March 2009 issue of The Quarterly Review of Biology. http://www.physorg.com/news156523249.html Biology Tue, 17 Mar 2009 15:41:28 EST news156523249 Too little vitamin D could be bad for more than your bones; it may also lead to fatter adolescents, researchers say. http://www.physorg.com/news156088325.html Medicine & Health Thu, 12 Mar 2009 14:52:47 EST news156088325 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, shows that females can discern a male's ancestry, age and possibly reproductive fitness from the chemical cocktail he exudes. http://www.physorg.com/news155283044.html Biology Tue, 03 Mar 2009 06:11:31 EST news155283044 Researchers at Uppsala University can now show that what is good for one sex is not always good for the other sex. In fact, evolutionary conflicts between the two sexes cause characteristics and behaviors that are downright injurious to the opposite sex. The findings are being published in the scientific journal Current Biology. http://www.physorg.com/news154350679.html Biology Fri, 20 Feb 2009 11:11:46 EST news154350679 Mating can be exhausting. When fruit flies mate, the females' genes are activated to roughly the same extent as when an immune reaction starts. This is shown in a study at Uppsala University that is now appearing in the scientific publication, Journal of Evolutionary Biology. http://www.physorg.com/news154266738.html Biology Thu, 19 Feb 2009 11:52:52 EST news154266738 Women have traditionally been viewed as being more social and cooperative than men. However, there is recent evidence that this may not be the case. In fact, studies have shown that men maintain larger social networks with other males compared to women and tend to have longer lasting friendships with members of the same-sex than do women. Psychologist Joyce F. Benenson from Emmanuel College, along with her colleagues from Harvard University and the Universite du Quebec a Montreal wanted to compare males' and females' levels of tolerance towards same-sex peers. http://www.physorg.com/news153576647.html Medicine & Health Wed, 11 Feb 2009 12:11:27 EST news153576647 Inbreeding can unexpectedly extend male lifespan. Insect experiments described in the open access journal BMC Evolutionary Biology have shown that, in seed beetles, inbreeding causes males to live longer, while shortening female lifespan. http://www.physorg.com/news153147399.html Biology Fri, 06 Feb 2009 12:57:37 EST news153147399