The #1 source for news about monkeys and apes

[Josh Greenman <joshg1973 AT yahoo.com>]

http://www.hindustantimes.com/news/181_283496,00040001.htm

Scent molecules help monkeys find mates: Study 
Asian News International
Washington, June 17 
 
Mating in simians is determined by highly specific scent molecules called 
pheromones,
which help in hunting a suitable partner, a new study has revealed.

However, human begins are not that lucky when it comes to pheromone signals. 
According to
Jianzhi George Zhang, evolutionary biologist at the University of Michigan, 
colour vision
puts human pheromones out of business.

Although humans and apes still carry genes that create pheromone receptors in 
the noses,
these genes have mutated to the point that they are merely pseudogenes and 
are not
functional any more.

Using the genes of people and primates to crack this intriguing puzzle, Zhang 
presented
his findings in the online Proceedings of the National Academy of Sciences.

Female New World monkeys have full colour vision because females have two X 
chromosomes
that harbour both red and green colour vision genes. But since males have 
only one X
chromosome, it leads to New World males having only one copy of either the 
red or green
gene, resulting in color-blindness.

A pheromone attaches to a water molecule, drifts about in the air currents 
and finally
lands on the proper receptor in someone else's nose. The receiver can't 
immediately be
sure about the sender and its origins, but sexual swelling helps everyone in 
the troop to
precisely locate the signal, even at a significant distance.

Sexual swelling occurs in about 10 per cent of all primate species, but only 
in the Old
World species of Africa and Asia, which is where humans probably originated, 
as well.