Urine sprays during courtship send mixed messages

Mar 29, 2010
Two crayfish fight in a cloud of visualized urine. Credit: Fiona Berry

Walking through urine drives crayfish into an aggressive sexual frenzy. Researchers writing in the open access journal BMC Biology suggest that a urine-mediated combination of aggressive and reproductive behaviour ensures that only the strongest males get to mate.

Fiona Berry and Thomas Breithaupt from the University of Hull, UK, investigated the effects of urine-based chemical signaling on sexually active crayfish. Breithaupt said, "Our results confirm that females initiate courtship behavior; males will only attempt to mate if they receive urinary signals from the female. Females, however, send a mixed message by releasing an aphrodisiac while also acting very aggressively towards the males".

Females could profit in different ways from displaying such conflicting signals. By stimulating in males, females can gauge male size and strength and thereby ensure that only the fittest males get to fertilise their eggs. According to the researchers, "Timing seems to be key to this interaction as urine induces in both sexes. Males will discontinue urine release early in the sexual encounter, which may mitigate the female's and enhance mating success".

Explore further: A step into the unmown creates a 'win-win' for wildlife and humans

More information: To signal or not to signal? Chemical communication by urine-borne signals mirrors sexual conflict in crayfish, Fiona C Berry and Thomas Breithaupt, BMC Biology (in press), www.biomedcentral.com/bmcbiol/

add to favorites email to friend print save as pdf

Related Stories

Piddling fish face off threat of competition

Dec 12, 2007

Research published today in the online open access journal, BMC Biology, shows that male tilapia fish use pheromones in their urine to fight off competitors and enforce social dominance.

Female guppies risk death to avoid sexual harassment

Aug 06, 2008

Sexual harassment from male guppies is so bad that long-suffering females will risk their lives to escape it, according to new research from Dr Safi Darden and Dr Darren Croft from Bangor University. Their work, which was ...

Mating that causes injuries

Feb 20, 2009

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 ...

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

Sep 20, 2007

Researchers have discovered that even the gruesome and brutal lifestyle of the Evarcha culicivora, a blood gorging jumping spider indigenous to East Africa, can’t help but be tempted by that ‘big is beautiful’ mantra ...

Sex is thirst-quenching for female beetles

Aug 28, 2007

Female beetles mate to quench their thirst according to new research by a University of Exeter biologist. The males of some insect species, including certain types of beetles, moths and crickets, produce unusually large ejaculates, ...

Recommended for you

Research helps steer mites from bees

12 hours ago

A Simon Fraser University chemistry professor has found a way to sway mites from their damaging effects on bees that care and feed the all-important queen bee.

Bird brains more precise than humans'

13 hours ago

(Phys.org) —Birds have been found to display superior judgement of their body width compared to humans, in research to help design autonomous aircraft navigation systems.

User comments : 0