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) -- 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 (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 Territorial behavior in male mice might be linked to more "girl-power" than ever suspected, according to new findings at UCSF. For the first time, researchers have identified networks of nerve cells in the brain that are associated with how male mice defend their territory and have shown that these cells are controlled by the female hormone estrogen. http://www.physorg.com/news173618739.html Biology Thu, 01 Oct 2009 12:26:12 EST news173618739 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 Walk into almost any household that includes teenage boys and you'll find one or more video game consoles. Walk into that household past 10PM and you`re likely to find one or more teenage boys playing those video games. Walk into the parents` bedroom, wake them up and then ask them what they think of their sons playing video games, and most likely they'll tell you it`s a waste of time - before they kick you out of their house. But is it truly a waste of time? http://www.physorg.com/news171724441.html Other Sciences Wed, 09 Sep 2009 14:40:07 EST news171724441 (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 Researchers studying the nervous control of nematode mating behavior have produced video footage of a male worm preparing to mate with a hermaphrodite. http://www.physorg.com/news165146102.html Biology Thu, 25 Jun 2009 10:55:23 EST news165146102 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 A newly released study by researchers at the University of Alaska Fairbanks offers evidence that in one breed of northern seabird, the size of males' feather crests may be more than simple ornamentation. http://www.physorg.com/news159126425.html Biology Thu, 16 Apr 2009 18:48:05 EST news159126425 (PhysOrg.com) -- When it comes to wooing females, males of all species -- even fruit flies -- try to gain a competitive edge. http://www.physorg.com/news158947334.html Biology Tue, 14 Apr 2009 17:02:49 EST news158947334 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 Researchers at the University of Pennsylvania School of Veterinary Medicine and Pennsylvania State University have identified for the first time a specific "niche factor" in the mouse testes called colony stimulating factor 1, Csf1, that has a direct effect on sperm stem cell self-renewal. Moreover, the study shows that the origin of this growth factor is the Leydig cell - located in the testes and stimulated by the pituitary gland to supply testosterone - that secretes Csf1 and enhances self-renewal of the stem cells. http://www.physorg.com/news155588652.html Biology Fri, 06 Mar 2009 19:08:17 EST news155588652 Young male lizards in South Africa imitate females to fool aggressive older males into leaving them alone, in an example of transvestism in the natural world, researchers have found. http://www.physorg.com/news155288676.html Biology Tue, 03 Mar 2009 07:45:13 EST news155288676 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 Nestled just off the east coast of Australia, picturesque North Stradbroke Island is a haven for local wildlife. Yet some of the inhabitants of the island's creeks and swamps are far from peaceful. Slender crayfish are aggressive territorial creatures, explains ecologist Robbie Wilson of the University of Queensland, Australia. When two crayfish catch sight of one another, they size each other up in a ritualistic display, which can quickly escalate from careful tapping of their opponent's chelae (enlarged front claws) to a full-blown fight. http://www.physorg.com/news154935911.html Biology Fri, 27 Feb 2009 05:45:57 EST news154935911 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 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 (PhysOrg.com) -- Women are not from Venus any more than men are from Mars. But even though both sexes are perfectly terrestrial beings, they are not lacking in other differences. And not only in their reproductive organs and behavior, either, but in such unsexy characteristics as the propensity for drug abuse, fine motor control, reaction to stress, moods and many brain structures. http://www.physorg.com/news152812170.html Medicine & Health Mon, 02 Feb 2009 15:50:10 EST news152812170 For the first time, male flies of a serious agricultural pest, the medfly, have been bred to generate offspring that die whilst they are still embryos. Researchers writing in the open access journal BMC Biology describe the creation of the flies that, when released into a wild population, could out-compete the normal male flies and cause a generation of pests to be stillborn - protecting important crops. http://www.physorg.com/news152263307.html Biology Tue, 27 Jan 2009 07:22:20 EST news152263307 (PhysOrg.com) -- That pesky buzz of a nearby mosquito is the sound of love, scientists have known for some time. But a new Cornell study reports that males and females flap their wings and change their tune to create a harmonic duet just before mating. http://www.physorg.com/news150650727.html Biology Thu, 08 Jan 2009 15:25:27 EST news150650727 Observing and betting on cricket fights has been part of Chinese cultural tradition since at least the Sung Dynasty (A.D. 960-1278). This ancient practice has resulted in quite a detailed list of characteristics that Chinese practitioners think make for champion fighters. "Because money was involved, there was a strong incentive for the practitioners of this sport to observe their cricket fighters closely," says Kevin Judge, a biology postdoctoral researcher at University of Toronto Mississauga. http://www.physorg.com/news150541753.html Biology Wed, 07 Jan 2009 09:09:13 EST news150541753 Shocking new research shows size isn't always an advantage in the animal world, shattering a widely-held belief that bigger is better. http://www.physorg.com/news148227762.html Biology Thu, 11 Dec 2008 14:22:42 EST news148227762 Big males outperform smaller ones in head-to-head mating contests but diminutive males make ten times better lovers because they're quicker to mature and faster on their feet, a new study of redback spiders reveals. http://www.physorg.com/news147927909.html Biology Mon, 08 Dec 2008 03:05:09 EST news147927909 When females aren't around, one species of parasitic nematode worm doesn't even bother to make any sperm, reveals a new report in the November 11th issue of Current Biology, a Cell Press publication. http://www.physorg.com/news145542963.html Biology Mon, 10 Nov 2008 12:36:03 EST news145542963 Suicide rates in those aged 10-19 in the UK declined by 28% in the seven year period from 1997-2003, shows a study published today in The Journal of Child Psychology and Psychiatry. The study, carried out by researchers at the University of Manchester, showed that the decline was particularly marked in young males, where rates declined by 35%. http://www.physorg.com/news143975669.html Medicine & Health Thu, 23 Oct 2008 10:14:29 EST news143975669