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'Casanova' field crickets - live fast, die young
SYDNEY, AUSTRALIA: Fit, well-fed male field crickets die young because they spend too much time courting members of the
opposite sex, according to research by Australian scientists in the latest edition of Nature.
The results reveal how male crickets (Teleogryllus commodus) fed on a high protein diet engaged in more "sexual calling" and
died sooner than males reared on a low protein diet. The well-fed males also died earlier than well-fed female crickets
(females don't "call" to males).
The scientists manipulated the crickets' dietary intake by feeding high, medium and low protein diets to three different
groups.
"The high protein fed male crickets spent the extra capital that they got from a better diet on mating behaviour, which
shortened their longevity," says Dr Luc Bussiere, a UNSW postdoctoral research fellow and co-author to the study. "So it's
obvious that for these crickets, a long life isn't all it's cracked up to be."
"Supporting the idea that well-fed crickets reduced longevity was a consequence of heightened sexual display ("calling)" was
the finding that males raised on both high and medium protein diets lost a greater proportion of their body weight after each
night's "calling" than those fed on a low protein diet," says UNSW's Dr John Hunt, an ARC postdoctoral research fellow.
Further, despite dying earlier than males fed on a low protein diet, well-fed males "called" more over the course of their
shortened lifetime compared to males fed on a low protein diet.
Moreover, males fed on high and medium diets tended to lose weight soon after they commenced their calling behaviour, whereas
those on low protein diets tended to delay their calling until later in adult life, thereby enabling them to gain or maintain
their body weight for longer.
"One thing that consistently prolongs lifespan in a range of species is a restricted diet. Now we know a bit more about how
this occurs in male crickets - by suppressing sexual advertisement," says UNSW co-author, Dr Rob Brooks.
According to UNSW co-author, Dr Bussiere, the best predictor of male mating success in Teleogryllus commodus is the quantity
of time spent calling females.
"We heightened this behaviour by manipulating dietary intake. For males on high protein diets it had the effect of promoting
their promiscuity and reducing their longevity. They literally knocked themselves out trying to impress female crickets," he
says.
"For humans this might seems counterproductive because we don't want to die young - we want to live long lives. But for
animals the goal isn't living longer - it's to reproduce."
MEDIA CONTACTS
DAN GAFFNEY 61-411-156-015 dgaffney@science.unsw.edu.au
DR JOHN HUNT (AH) 61-408-096-341 (BH) 612-9385-2075 http://www.anu.edu.au/BoZo/hunt/index.html
DR ROB BROOKS (AH) 61-402-446-847 (BH) 612-9385-2587 rob.brooks@unsw.edu.au
FUNDING
Drs John Hunt and Rob Brooks were funded by an Australian Research Council grant. Dr Bussiere was funded by a Natural
Sciences and Engineering Research Council Fellowship (Canada).
Paper reference: Nature letters: 'High quality male field crickets invest heavily in sexual display but die young.' John
Hunt, Robert Brooks, Michael D Jennions, Michael J Smith, Caroline J Bentsen, Luc F. Bussiere. Nature vol 432, 23-30 Dec
2004.
STRICT MEDIA EMBARGO APPLIES:0500 hrs (Australian EDST) Thursday 23 December 2004. 1300 hrs (Eastern US time) Wednesday 22
December 2004. 1800 hrs (London) Wednesday 22 December 2004.
Contact: Dr Rob Brooks
rob.brooks@unsw.edu.au
61-402-446-847
University of New South Wales
"Casanova" domeniul crickets - vii repede, mor tineri - 'Casanova' field crickets - live fast, die young - articole medicale engleza - startsanatate