How females control sperm storage to pick the best dad

September 30th, 2009 WASHINGTON - After sex, female fruit flies ditch the usual siesta in favour of extra foraging and searching for places to lay her eggs, a new study has found. The study showed that it is all down to a chemical or 'sex peptide' produced by male fruit flies.

August 22nd, 2009 WASHINGTON - A new study has shown that female fruit flies prefer keeping sex short and sweet because they get a reproductive boost from shorter intercourse. Since males like sex to last longer, a fight ensues.

July 10th, 2009 MELBOURNE - A new piece of research on red junglefowl, an ancestor of chickens, has shown that males can adjust the speed and effectiveness of their sperm, based on whether they find their mate attractive. Published in the Proceedings of the Royal Society B, the study adds to the growing body of evidence that males from promiscuous species, including humans, increase the chances of fertilisation when the female is deemed to be attractive.

July 10th, 2009 LONDON - Attractive males release fewer sperm per mating to maximise their chances of producing offspring across a range of females, according to a new study. The findings by researchers at UCL (University College London) and the University of Oxford suggest that, paradoxically, mating with attractive males may be less fertile than those with unattractive ones.

July 10th, 2009 WASHINGTON - A team of University College London and University of Oxford researchers say that a study on the evolution of ejaculation strategies has shown that attractive males release fewer sperm per mating to maximise their chances of producing offspring across a range of females. Writing about their findings in the journal American Naturalist, the researchers say that their findings suggest that, paradoxically, matings with attractive males may be less fertile than those with unattractive ones.

July 9th, 2009 LONDON - Scientists are calling for more tests to ensure that artificial sperm created by some British researchers are identical to their natural counterpart, saying that further proof may make them a valuable tool to understand male infertility. Karim Nayernia and his colleagues at the University of Newcastle recently treated male embryonic stem cells (ESCs) with a range of substances, which converted them first into germline stem cells, and finally into spermatogonial stem cells.

July 1st, 2009 WASHINGTON - Having sex every day improves men's sperm quality, an Australian study has revealed. In a study of men with fertility problems, researchers found that daily ejaculation for a week cut the amount of DNA damage seen in sperm samples.

June 18th, 2009 Tiny crustacean big on reproductionWASHINGTON — When it comes to sexual reproduction, it turns out that size does matter, at least for a group of ancient crustaceans called ostracods. Modern versions of these tiny animals also have extra large sperm, but not to the extent of their relatives 100 million years ago, researchers report in Thursday's edition of the journal Science.

June 17th, 2009 LONDON - An American researcher has shown that female giant pandas can tell one male's love calls from those of others, taking the first step towards proving that females among the animals use these bleats to choose their mates. Ben Charlton, a biologist at Zoo Atlanta, says that this finding attains significance as a gaining a better understanding of how females pick their mates might help zoos breed the notoriously picky and endangered animals.

June 16th, 2009 WASHINGTON - Researchers at McMaster University have discovered the existence of two types of males of a fiercely invasive fish spreading through the Great Lakes, which might help explain how they rapidly reproduce. They revealed that in addition to round goby males, which guard the nest from predators and look after their offspring, there exists what scientists call "sneaker" males - little males that look like females and sneak into the nests of the larger males.

June 15th, 2009 LONDON - Biologists studying sperm whales in the North Atlantic have found that mothers use organised babysitting sessions so they can go hunting for food. Scientists at the University of St Andrews, Durham University and Dalhousie University in Halifax, Nova Scotia, have discovered that females share responsibility for the younger members of a pod by establishing networks of carers.he whales are specially adapted to allow them to make long, deep dives.

June 12th, 2009 WASHINGTON - A study on flies of the species Drosophila montana has shown that females engaged in extended intercourse wait longer before they mate again, increasing the first fly's chances of fathering offspring. Published in the open access journal BMC Evolutionary Biology, the study explains why males favour longer copulation times.

May 15th, 2009 WASHINGTON - By altering parts of male genitalia in tsetse flies, researchers induced changes in female reproduction, including reduced ovulation, reduced sperm storage and increased re-mating attempts by the females. 'To the best of our knowledge, this was the first study to look at female choice following experimental manipulation of both male and female genitalia,' said William Eberhard, staff scientist at the Smithsonian Tropical Research Institute (STRI) and professor of biology at the University of Costa Rica.

April 13th, 2009 WASHINGTON - Fertility specialists heralded the birth of a baby girl who was conceived through in-vitro fertilisation (IVF) at their lab with sperm frozen 21 years ago, a world record. Chris Biblis, 38, of Charlotte (US) was treated for leukemia from age 13 to 18.

April 8th, 2009 WASHINGTON - Does love at first sight actually happen? Well, scientists say that the answer to this ever-existing query lies in geneticists. In a study on fruit flies, American and Australian researchers have discovered that some males and females are more compatible than others at the genetic level.