|
Source:Smithsonian Tropical Research Institute
Date: May 9, 2007
New Take On Sexual Signaling
Science
Daily — In dangerous environments, females
looking for a mate run great risks.
Scientists from Seoul National University, in Korea, and the
Smithsonian Tropical Research
Institute in Panama present a new take on sexual
signaling in the May issue of the Public
Library of Science. The researchers report that
females prefer a male sexual signal that helps
them avoid their predators as they
sequentially visit and assess potential mates.
 |
Male Fiddler Crab, Uca terpsichores,
with hood. (Credit: John Christy, STRI
Staff Scientist) |
The traditional explanation for the
evolution of outrageous sexual signals like the male
peacock's plumage is that showy males attract females and
give them better offspring. Showy
males escape from
predators despite their highly conspicuous ornaments and
behaviors--proof
of their superiority.
"In our study of fiddler crabs, the strength of female
preference for a male signal that increases
her own survival
increases with her perceived risk of predation. That a
female's choice of a
mate is based on sexual signals that
benefit her directly is a fundamentally new and perhaps
widely applicable idea," said Tae Won Kim, who did this work
as a student at Seoul National
University and is now a
post-doctoral fellow at Ewha Women's University in Korea.
As the tide recedes, revealing great expanses of Pacific
beach, fiddler crabs (Uca terpsichores)
segue in and out of
their burrows, dodging predatory shorebirds. Male crabs
build hood-like
sand castles next to the entrance of their
burrows, attracting the attention of females by waving
their
one, super-sized claw.
Females prefer males that have built hoods to males that
have not. When they run across the
beach to check out or
mate with a male, they orient visually to both the waving
male and to his
hood. In this way they reach the male's
burrow quickly and directly and avoid their predators.
"When we bait predatory birds into the area--artificially
increasing the risk of predation,
females show an even
greater preference for males who have built hoods," said STRI staff
scientist John Christy, who has studied sexual
selection in this group for nearly 35 years. This
study
illustrates how the ecology of choosing a mate can shape
sexual communication.
"Conspicuous male sexual signals need
not advertise the quality of the signaler as a mate,"
Christy suggests. "Some may simply allow choosy females to
stay safe."
Ref. Tae Won Kim, John H. Christy, Jae C. Choe. 2007. A
preference for sexual signal keeps
females safe. Public
Library of Science ONE. DOI 10.1371/journal.pone.0000422
Funded by the Korean Research Foundation and Ewha Women's
University.
Note: This story has been adapted from a news release
issued by Smithsonian Tropical
Research Institute.
Female
Libido Enhancer
Attention
Ladies:
Increase your sexual
libido and orgasmic
capability by taking two
tablets
per
day (one with
breakfast and
one
with dinner) of Tribulus Terrestris, available
for your
purchase at
an
affordable
price at Female Libido
Enhancers. Take one tablet with
one full glass
of water at breakfast
and
again at dinner.
Erectile
Dysfunction
Herbal
Remedies
Stop
erectile dysfunction and
erection
problems from hurting
your love life by taking
the
following erection pills two
hours
before sexual activity: (1) one
tablet of Tongkat
Ali; (2) one
tablet
of
Tribulus Terrestris; and (3) two
tablets
of Arginine. Take
with
one
full glass
of
water
at
meal time. You can buy all
three
herbal sex enhancers
at an
affordable
price at
Male
Erection
Problems.
Be trained online and designated as a Certified Herbalist for only
US$500 and attract many
clients by being listed in the
Certified Herbalists Directory.
|
|
