Drinking from a spiny penis


(Fleur Champion de Crespigny)

Researchers at the University of Exeter have found that female bruchid beetles (Callosobruchus maculatus, above) mate when they are thirsty.

Evolutionary biologist Martin Edvardsson kept some female bruchids with, and others without, access to water. All the females were given the opportunity to mate with a new male every day.

In the journal Animal Behaviour, Edvardsson reports that those females without access to water mated more frequently - up to 40% more - than those with access to water. This leads him to conclude that female bruchid beetles mate in order to obtain water from the male's ejaculate when they are dehydrated.

During mating, the female absorbs water through the walls of the reproductive tract. But mating also has its costs. For the female, it is a tricky and painful business: the male's genitalia (below) are covered with spines which unfurl during copulation, puncturing the female's reproductive tract.



(Johanna Ronn/ Goran Arnqvist

When copulating, females use their hindlegs to kick their mates. This reduces the duration of copulation, and, therefore, the amount of damage inflicted by the male's spiky geitalia.

A cost/benefit analysis is therefore essential to the mating behaviour of the female. The number of mating events must be strictly limited because of the resulting harm. But at the same time, the female's needs for both sperm and water must be met.

Male bruchids are therefore amongst those insect species that have evolved very large ejaculates. In some species, the ejaculate can account for up to 10% of the insect's body weight. The larger a male's ejaculate is, the more water the ejaculate will contain.

During mating, the female receives the water in the ejaculate as a "nuptial gift". The larger the amount of water contained within it, the longer it will be before the female mates with another male, and the less likely is the possibilty of sperm competition.

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I didnt know that an HGH Spray (FDA approved) could make your penis grow, so I read some information on the net - and I tried the "Dr. Max Powers HGH Spray" (I bought the 3-pack to save money from www.drmaxpowers.com).

Been on them for about 25 days now and I have about 2months to go - but here are my results:

Although I have noticed Length Gains like others have, here are the drastic results I have realized:

- I have noticed increasingly harder erections and that last much longer (giving my partner a much longer experience - and delaying me a bit to be a bit more explosive).

- It seems much easier to get an erection in no time

- It will deffinately change your sex life...in this ALONE I give it an excellent review.

- We will see in time if it actually makes a size difference - but for now - I love the results!!

I guess hydrating your mate this way beats getting your head nibbled off, mantis-style, unless, of course, you're into that...

By Malcolm J. Brenner (not verified) on 28 Aug 2007 #permalink

Wow, how could one NOT click on a post with a title like this one?!?

BTW, should it not be "when *they* are thirsty" in the first line?

By ctenotrish, FCD (not verified) on 28 Aug 2007 #permalink

I see my strategy to get millions of hits is working...

Thanks for pointing out the missing word.

I find this topic to be fascinating....the idea of female driving mate choice based upon resources is not something seen very often.

I beg to differ...material resources are something human females often take into consideration when deciding upon a long-term partner.

But I ain't sayin' all women are gold diggers.

This may be a dumb question, but why did the males evolve to have the spines in the first place? I could understand evolving spines or spike to prolong mating as with cats(I think?) but if anything the presence of spines here gives the males less time to mate.

By Joshua Zelinsky (not verified) on 31 Aug 2007 #permalink