X-rated worm movies reveal sex secrets
By AMY MAXMEN - NATURENEWS - NATURE.COM
Added: Wed, 12 Jan 2011 14:22:39 UTC
Sperm design and mating behaviour co-evolve.
By watching countless hours of hermaphroditic worm sex, Lukas Schärer and his wife Dita Vizoso, evolutionary biologists at the University of Basel in Switzerland and their colleagues, have discovered evidence for a theory that has eluded testing for nearly a century: sex shapes sperm. Their findings, including videos of the mating worms, are published today in the Proceedings of the National Academy of Sciences
Sperm are the most diverse of animal cells, variously adorned with tails, hairs, hooks, bristles and more. "But we don't know what any of those doodads do," says Scott Pitnick, an evolutionary biologist at Syracuse University in New York. Fertilization is not easy to observe, and predictions about the function of sperm design are even harder to test, so it took a group of transparent and rather kinky flatworms to unravel a piece of the puzzle. The creatures are simultaneous hermaphrodites: each has both male and female genitalia. The worms are about the size of a comma, but readily mate under a microscope.
The heterosexual world of animal reproduction is populated primarily by males eager to mate and females more concerned with finding a superior partner, but simultaneous hermaphrodites face antagonistic desires at the same time. Flatworm species in the genus Macrostomum solve the conflict by allowing eager sex to come first, and selectivity to follow.Read more
Stephen Cave - Financial Times Comments
What we really know about our evolutionary past – and what we don’t
- - Ancestors Trail Walk Comments
WALK DARWIN’S TREE OF LIFE ~ 26 AUGUST 2012 - event begins on Saturday 25 August
Liat Clark - Wired.co.uk Comments
Astrophysicists simulate 14 billion years of cosmic evolution in high resolution
Alok Jha - The Guardian Comments
Cambridge scientists claim DNA overlap between Neanderthals and modern humans is a remnant of a common ancestor
- - Science Blog Comments
Why, after millions of years of evolution, do organisms build structures that seemingly serve no purpose?
Charles Choi - CBS News Comments
Four decades ago, in 1972, the Koobi Fora Research Project discovered the enigmatic fossilized skull known as KNM-ER 1470 which ignited a now long-standing debate about how many different species of early Homos existed.