Bird Dads Suffer Infidelity But Bring Up Baby
...tecompared with most bird species. While a single copulation would provide enoughsperm to fertilize a clutch of four eggs, the researchers found jacanasaveraging 65 copulations for each clutch produced. -- When no extra males were available in a harem, all chicks were sired by thecare-taking male. Thus a male...Presence of a fertile female in the next nest can lead a bird astray, UB research finds
...se females and does not guard his own matefrom the copulation attempts of other males," said Webster. That, in turn, makes the mates of the straying males that much more vulnerableto attention from other roaming males, thereby escalating the chances that themale also will find extra-pair young in his nest when ...PCB exposure is bad news for the female sex drive
...les more oftenand took longer to return after each copulation attempt by the males (Bulletinof Environmental Contamination and Toxicology, vol 62, p 664). "We found thatfemales stayed away from the males for longer," says Chung. Chung suspects that during a crucial phase of development, theoestrogen-mim...Blister beetles use sex and subterfuge to infiltrate bee's nests
...searchers believe the aggregations lure males into copulation through a combination of visual and olfactory cues. They noted that triungulin masses position themselves on vegetation much like female bees-perched on the top of a plant stem-and males approach and land on masses and females in the same way. To tes...Sex and genetics: Why birds are unfaithful to their partners
...use to assess relatedness with a potential mate or copulation partner. Another intriguing possibility that can explain why extra-pair paternity occurs when mates are more related has to do with the mechanism of sperm competition. If most females copulate occasionally with other males, then sperm of the social m...Female gluttony blamed on male tick
...ll her to complete engorgement. Within 24 hours of copulation she will increase another 10 times her unfed weigh...0 times her unfed weight and the third phase after copulation when the female increases her weight a further 10-fold. The virgin tick, however, rarely exceeds the...Casanova or caveman: Scientists isolate nerve cells that choreograph male fly's courtship behavior
...enitalia with his proboscis, followed by attempted copulation (step five) and copulation (step six). "A normal male completes the first three steps in about two minutes," Baker said. "That'...Circadian clock genes reign in duration of fruit fly copulation
...the length of the fly's copulation. The effects on copulation are independent of light and the 24-hour circadian...ss," exhibited an altered sexual behavior in which copulation time was significantly extended. Whereas copulation normally lasts for around 15 minutes, males carr...