sex in Biological News

Beautiful plumage: Feather color and sex start the species revolution

Faculty of 1000, the leading scientific evaluation service, has highlighted research providing evidence for the evolution of a new species. Birds use plumage colour to recognize and select potential mates. A mutation of a single DNA base can lead to a striking colour change, as demonstrated by ...

Parasitic worms make sex worthwhile

BLOOMINGTON, Ind. -- The coevolutionary struggle between a New Zealand snail and its worm parasite makes sex advantageous for the snail, whose females favor asexual reproduction in the absence of parasites, say Indiana University Bloomington and Swiss Federal Institute of Technology biologists in ...

Yeast missing sex genes undergo unexpected sexual reproduction

DURHAM, N.C. An emerging form of the pathogenic yeast Candida is able to complete a full sexual cycle in a test tube, even though it's missing the genes for reproduction. And it may also do so while infecting us, according to Duke University Medical Center researchers. "Sex contributes to t...

The story of X -- evolution of a sex chromosome

Berkeley -- Move over, Y chromosome it's time X got some attention. In the first evolutionary study of the chromosome associated with being female, University of California, Berkeley, biologist Doris Bachtrog and her colleagues show that the history of the X chromosome is every bit as interest...

Biologists discover gene behind 'plant sex mystery'

An enigma unique to flowering plants has been solved by researchers from the University of Leicester (UK) and POSTECH, South Korea. The discovery is reported in the journal Nature on 23 October 2008. Scientists already knew that flowering plants, unlike animals require not one, but two s...

Individuals vary their immune response according to age, sex and the costs

Is it always good to respond maximally when pathogens or disease strike, or should individuals vary their immune response to balance immediate and future costs? This is the question evolutionary physiologists Oliver Love, Katrina Salvante, James Dale, and Tony Williams asked when they examined how...

How 'secondary' sex characters can drive the origin of species

BLOOMINGTON, Ind. -- The ostentatious, sometimes bizarre qualities that improve a creature's chances of finding a mate may also drive the reproductive separation of populations and the evolution of new species, say two Indiana University Bloomington biologists. In the September 2008 issue of E...

Fish with temperature-dependent sex determination face global warming

In vertebrates with separate sexes, sex determination can be genotypic (GSD) or temperature-dependent (TSD). TSD is very common in reptiles, where the ambient temperature during sensitive periods of early development irreversibly determines whether an individual will be male or female. The number ...

U of T discovers environmental factors linked to sex ratio of plants

TORONTO, ON. Environmental factors can transform the ratio of females to males in plant populations according to new research out of the University of Toronto. The study conducted by Ivana Stehlik, a lecturer, Jannice Friedman, a PhD candidate, and Spencer Barrett, a professor, involved a ...

A new analysis method allows to find out the sex of the baby from the second month of pregnancy

The spin off of the University of Granada Lorgen, in collaboration with the Foetal Medicine Unit of the Maternity Hospital Virgen de las Nieves of Granada, has managed to develop a genetic trial that identifies the sex of the foetus from the eighth week of pregnancy separating the DNA found in th...

Fungi can tell us about the origin of sex chromosomes

Fungi do not have sexes, just so-called mating types. A new study being published today in the prestigious journal PLoS shows that there are great similarities between the parts of DNA that determine the sex of plants and animals and the parts of DNA that determine mating types in certain fungi. ...

Too much sugar turns off gene that controls the effects of sex steroids

(Vancouver November 8, 2007) Eating too much fructose and glucose can turn off the gene that regulates the levels of active testosterone and estrogen in the body, shows a new study in mice and human cell cultures thats published this month in the Journal of Clinical Investigation. This discover...

Worms take the sniff test to reveal sex differences in brain

Buttery popcorn or fresh green vegetables? Your answer tells a lot about you. Now, scientists say that the way that thousands of tiny worms have answered that question likely reveals a lot about you and your brain, too. In the experiment at the University of Rochester Medical Center, worms t...

The best both of worlds -- how to have sex and survive

Researchers have discovered that even the gruesome and brutal lifestyle of the Evarcha culicivora, a blood gorging jumping spider indigenous to East Africa, cant help but be tempted by that big is beautiful mantra no matter what the costs. A study recently published in Ethology found that despite ...

Influence of sex and handedness on brain is similar in capuchin monkeys and humans

Hiram, Ohio, August 29, 2007 Capuchin monkeys are playful, inquisitive primates known for their manual dexterity, complex social behavior, and cognitive abilities. New research now shows that just like humans, they display a fundamental sex difference in the organization of the brain, specifical...

First finding of a metabolite in 1 sex only

Researchers at the University of Illinois at Chicago have discovered a chemical compound in male blue crabs that is not present in females -- the first time in any species that an entire enzyme system has been found to be activated in only one sex. The research, performed using nuclear magneti...

Study finds role for parasites in evolution of sex

What's so great about sex? From an evolutionary perspective, the answer is not as obvious as one might think. An article published in the July issue of the American Naturalist suggests that sex may have evolved in part as a defense against parasites. Despite its central role in biology, sex i...

Men are the weaker sex

Nurses in the maternity ward often say that a difficult labor is a sign of a baby boy. Now, a Tel Aviv University study provides scientific proof that a male baby comes with a bigger package of associated risks than his female counterparts. In a study of 66,000 births, Prof. Marek Glezerman, c...

U of Minnesota researcher finds link between aggression, status and sex

Have you ever wondered why it seems like the littlest things make people angry? Why a glance at the wrong person or a spilled glass of water can lead to a fist fight or worse? University of Minnesota researcher Vladas Griskevicius has three words to explain why people may be evolutionarily incline...

Lightweight and long-legged males go the distance for sex

Finding a mate can take considerable legwork as recently illustrated by the flightless and nocturnal Cook Strait giant weta Deinacrida rugosa. This cricket relative is found in New Zealand and is one of the world's heaviest insects with females weighing in at 20 g, averaging twice the size of male...

Gene in male fish lures females into sex

A gene has been found in male cichlid fish that evolved to lure female fish so that male cichlids can deposit sperm in the females mouths. A study in the online open access journal BMC Biology reveals that the gene is associated with egg-like markings on the fins of cichlid fishes and uncovers the...

The benefits of 80 million years without sex

Scientists have discovered how a microscopic organism has benefited from nearly 80 million years without sex. Bdelloid rotifers are asexual organisms, meaning that they reproduce without males. Without sex, these animals lack many of the ways in which sexual animals adapt over generations to su...

Living fossils have hot sex

University of Utah scientists discovered a strange method of reproduction in primitive plants named cycads: The plants heat up and emit a toxic odor to drive pollen-covered insects out of male cycad cones, and then use a milder odor to draw the bugs into female cones so the plants are pollinated....

The penalty of having a sister -- why sibling sex matters for male saiga antelopes

Having a twin sister could put male saiga antelopes at a reproductive disadvantage, says new research published today. The study shows that male twins with a sister are born lighter than those with a brother, making them smaller than the optimal size for males. The research also shows that saigas a...

No sex for 40 million years? No problem

A group of organisms that has never had sex in over 40 million years of existence has nevertheless managed to evolve into distinct species, says new research published today. The study challenges the assumption that sex is necessary for organisms to diversify and provides scientists with new insigh...

Bird sex is something else

We’ve all heard about the birds and the bees. But apparently when it comes to birds, they have an unusual take on his and hers ?and the difference is genetic. Species with differentiated sex chromosomes (X and Y in humans, for example) get around the fact that males and females get different-sized ...

New clues to how sex evolves

Sex is a boon to evolution; it allows genetic material from parents to recombine, giving rise to a unique new genome. But how did sex itself evolve" Researchers at the Department of Energy's Lawrence Berkeley National Laboratory and the University of California at Berkeley have found clues to one p...

Embryonic selection of sex avoids conceiving blind children

The Assisted Reproduction Unit at the Quirón Hospital in Donostia-San Sebastián has managed, for the first time in the Basque Country, to successfully carry out an embryonic sex selection in a woman who is a carrier of the disease Retinosis Pigmentaria, linked with the X chromosome ?in order to avo...

Study challenges myth that sex late in pregnancy hastens birth

A new study debunks the widely held belief that engaging in sexual intercourse during the final weeks of pregnancy can hasten labor and delivery. In fact, just the opposite was true in 93 women studied at Ohio State University Medical Center. Women who were sexually active in the final three week...

Study: Competition for sex is a 'jungle out there'

Mother Nature could use a few more good pollinators, especially in species-rich biodiversity hotspots, according to a new study in the Proceedings of the National Academy of Science (PNAS). Jana Vamosi, Ph.D, postdoctoral associate at the University of Calgary and Tiffany Knight, Ph.D., assistant...

Ocean 'dead zones' trigger sex changes in fish, posing extinction threat

Oxygen depletion in the world’s oceans, primarily caused by agricultural run-off and pollution, could spark the development of far more male fish than female, thereby threatening some species with extinction, according to a study published today on the Web site of the American Chemical Society jour...

Hanging baskets of sex and death help fruit growers

A hanging basket style device is at the heart of a plan by researchers at the University of Warwick to harness the sex drive of a major pest of fruit orchards as a weapon to spread a virus to kill that very same pest. The device allows growers to selectively target the pest with a virus that ...

Secret sex life of killer fungus?

Aspergillus fumigatus is a medically important fungus, causing potentially life-threatening infections in patients with weakened immune systems. It is also a major cause of respiratory allergy, and it is implicated in asthma as well. The fungus has always been thought to lack the ability to reprodu...

Why were the HIV prevention trials in commercial sex workers abandoned?

One promising approach to help stem the global HIV epidemic is to give commercial sex workers an HIV medication (such as the drug tenofovir) before they have high risk sex in the hope of reducing their chances of becoming infected, an approach called "pre-exposure prophylaxis" (PREP). But activist ...

New study: Sexually transmitted disease treatment can be effectively administered by sex partners

Effective control of sexually transmitted diseases (STDs) requires treatment of the sexual partners of infected patients. A new study shows that providing infected men with antibiotics to give their partners is more effective than traditional means of contacting and treating the partners, according...

Radio-tracking associated with 'dramatic shift' in water vole sex ratio

Wildlife researchers are being warned that radio-tracking could be affecting the animals they are studying. According to new research published today in the British Ecological Society's Journal of Applied Ecology, fitting radio-collars to water voles was associated with a "dramatic shift" in the se...

Female sex hormones play a vital role in defense against sexually transmitted diseases

Two McMaster University studies, to be published in the Journal of Virology, show that sex hormones have a profound effect on susceptibility of female mice to the herpes simplex virus, type 2 (HSV-2 ), one of the most common sexually transmitted diseases. Charu Kaushic, assistant professor and s...

Sex in the Caribbean: Environmental change drives evolutionary change -- eventually

...e, it's better not to fragment. Nutrients to form eggs and sperm needed for sex can, on the other hand, accumulate slowly over time. O'Dea, with Jeremy ...ps Institution of Oceanography, measured the relative amount of cloning and sex occurring in species over the last 10 million years in the Caribbean. "The ...

UC San Diego's $3 million NSF grant to fund science festivals

...need for science outreach in the community: "Here in America, we take pride in providing the best opportunities for everyone, regardless of race, age, sex or financial status. Programs that support science and mathematics in schools must be offered to even the poorest schools if this nation is to live up...

Sex involved in plant defense

...lly with the remainder reproducing asexually to gauge the effects of plant sex on defense mechanisms. The researchers found that so-called generalist herb...ow more rapidly and propagate even when pollination is not possible losing sex puts plants at a long-term disadvantage. "In the end, asexual reproduct...