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"Upon climax with the queen, he explodes, and his genitals rip from his body - Open Knowledge — LiveJournal

Feb. 18th, 2003

01:07 am - "Upon climax with the queen, he explodes, and his genitals rip from his body

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Most interesting quote:

"....Among green-veined white butterflies, for example, a virgin male ejaculates a sperm packet roughly 15 percent of his weight that also contains nutritious substances. Females that have sex with several virgins lay more and bigger eggs than those that do it with only one or with males that have lost their virginity and consequently make sperm packets only half the size of their virgin glory...."


http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/02/17/MN108820.DTL

This is not your father's birds and bees
Recent research challenges notion of female monogamy

Carol Cruzan Morton, Special to The Chronicle Monday, February 17, 2003

Bar the doors and break out the chastity belts, boys, because girls of most species sleep around, and it's for their own good, if not yours.

For generations, biologists had assumed females to be naturally chaste, while males were renowned for their promiscuity. Even Charles Darwin, who invented the idea of sexual selection, didn't dare challenge the Victorian morals of his day. Man evolved from ape, fine. But an immodest and lustful Mother Nature? Heaven forbid!

Now, hundreds of studies and a spate of books are challenging that conventional wisdom. Females of many species, it turns out, have evolved strategies for passing on their genes that involve copulating with multiple males -- and recognition of that fact is literally changing our view of the birds and the bees.



"Natural selection, it seems, often smiles on strumpets," says evolutionary biologist Olivia Judson, author of "Dr. Tatiana's Sex Advice to All Creation," the most recent and entertaining book exploring the variety of female harlotry.

"As a rule, loose females have more and healthier children."

To be sure, biologists are examining these questions in the dispassionate light of scientific inquiry. In describing their theories, they prefer the more neutral term "polyandry," meaning many males, instead of "promiscuity." And they caution laypeople not to look to nature's own apparent infidelities for any justification of their own behavior.

The misbegotten idea that males evolved to make love and females to demur gained scientific currency in the late 1940s in fruit fly experiments by Angus Bateman, a British scientist who reached his erroneous conclusions in part because his experiments lasted only three or four days.

Had he run his experiments longer, he might have discovered that male black- bellied fruit flies secrete an anti-aphrodisiac in their semen that's relatively short lived. As soon as it runs out, females become interested in copulating again.

On the surface, the conventional view made sense. Sperm seemed to come cheap to males, while eggs were expensive to females, which have to invest the time to raise offspring. Scientists could not fathom any possible benefit of multiple partners of females, and they could come up with plenty of potential costs, such as sexually transmitted diseases.

BIRDS DO IT

Then came DNA paternity testing. In one species after another, it turned out that biologists were as cuckolded as the males they had been observing. The first and most extensive examples of polyandry were found among avian species, which was quite a shock to scientists because birds had appeared to be paragons of traditional family values.

"The way the male and female rush back and forth to their demanding brood of chicks seems like nature's model of good parenting," says Marlene Zuk, biology professor at UC Riverside and author of "Sexual Selections: What We Can and Can't Learn About Sex From Animals."

"Now, we find that they're actually in the same situation as millions of modern-day husbands and wives, eyeing a child warily and making uneasy jokes about the milkman," she says.

DNA testing in chicks of seemingly monogamous females showed a wide range of extra mates. In one study, for example, as much as 90 percent of the offspring of the brilliantly colored Australian fairy wren were from mates other than the presumed father.

Biologists have struggled to come up with broad theories for why females benefit from playing the field, but so far the reasons seem to vary widely according to species. A lot of complex theory boils down to this: A gal's got to do what's necessary to ensure the survival of her genes.

In some cases, females may get more help around the home. Among bronze- winged jacana, for example, harems of up to four males do all the child care, enabling a female to have four times as many broods. Male greater rheas, flightless South American birds that resemble ostriches, receive eggs from several females, incubate them and rear all the chicks, while females go off to mate and lay other clutches.

In other cases, females swap sex for food -- the more sex, the more food and the healthier their offspring.

Among green-veined white butterflies, for example, a virgin male ejaculates a sperm packet roughly 15 percent of his weight that also contains nutritious substances. Females that have sex with several virgins lay more and bigger eggs than those that do it with only one or with males that have lost their virginity and consequently make sperm packets only half the size of their virgin glory.

SURVIVAL OF THE LOOSEST

In other cases, promiscuity is simply a matter of survival. Male chimpanzees, for example, have been known to kill infants not their own. Frequent sex with several males -- in one 15-minute period, a female was observed having sex with eight males -- can heroically confuse paternity and act as insurance against harm to her offspring.

But while females are busy ensuring their genetic survival by sleeping around, males have not been idle. After all, female promiscuity puts the genes of males at risk. It's no good being Don Juan, seducing all the females in sight, if none of them uses your sperm, Judson says. So males have developed counterstrategies to ensure their genetic survival.

"This is perhaps the most significant discovery of the past two decades, that male and female attributes coevolve," writes Tim Birkhead, professor of behavioral ecology at the University of Sheffield in Britain and author of "Promiscuity: An Evolutionary History of Sperm Competition."

SOME MALES' WEAPONS LETHAL

In the arms race between the sexes, males of some species have developed penises that are more than sperm delivery devices.

Damselflies, close relatives of dragonflies, have penises with inflatable balloonlike bulbs, two horns at the tip and long bristles down the sides. In one species, males use this to scour sperm from inside a female before depositing his own. In another, males use it for extra stimulation, inducing her to eject sperm from previous lovers.

Male honeybees, on the other hand, sacrifice themselves on the altar of love. Upon climax with the queen, he explodes, and his genitals rip from his body, leaving the mutilated member as a kind of chastity belt.

"You might imagine that male honeybees would have evolved some way of removing the chastity belt. You'd be right," Judson says. "If you look closely,

you'll see that each male honeybee sports, on the tip of his phallus, a hairy structure that can dislodge the severed genitalia of his predecessor."

Other species resort to guarding their mates. A possessive postcoital male Idaho ground squirrel, for example, won't let his partner out of his sight and follows her everywhere, stationing himself at the entrance to her burrow and picking fights with other males that happen to come near.

When it comes to Homo sapiens, scientists urge us not to read too much into all this. Depending on their point of view, people may be horrified or intrigued by the infidelity of the birds and the bees, but in truth birds aren't cheating, they're just doing what they do.

"If we try and use their behavior as a model or justification for our own," says Zuk, the UC Riverside biologist, "we not only run the risk of making decisions about our morals on very shaky grounds, we miss what is interesting and vital about the animals' own behavior."
NEW LOOK AT REPRODUCTION

Females of many species have sex with multiple partners. Males, in turn, have adapted ways to ensure that their genes, and not those of competitors, are passed on. Understanding this co-evolution is changing our view of male and female sex roles.

Among reed buntings, small brown songbirds, every male a female has mated will come flying to her defense. But her infidelity can backfire if the female's main squeeze suspects her of cheating.

Male honeybees sacrifice themselves on the altar of love. Upon climax with the queen, he explodes and his genitals rip from his body, leaving the mutilated member as a kind of chastity belt.

Male chimpanzees sometimes murder infants not their own. So females have adopted a strategy of confusing paternity by having frequent sex with several males.

Comments:

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From:mattraibert
Date:February 18th, 2003 06:09 am (UTC)
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Very interesting.

My name is Matt. You added me and I've added you back.

::extends hand:: good to meet you.

Also, you may want to check out http://www.neoteny.org/ if you haven't already. It has some excellent archives on aspects of evolution. It's sister site http://www.humanevolution.net/ is also worth a visit.
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From:mattraibert
Date:February 18th, 2003 06:11 am (UTC)
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Oh, shit. Now I'm all confused.

It seems I was duped by what I thought was an LJ-cut but was in fact a link to your journal.

Well, hello I guess. I didn't add you. But if you respond to this I probably will.
I apologize for any inconvenience.
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From:afb
Date:February 18th, 2003 07:43 am (UTC)
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Other species resort to guarding their mates. A possessive postcoital male Idaho ground squirrel, for example, won't let his partner out of his sight and follows her everywhere, stationing himself at the entrance to her burrow and picking fights with other males that happen to come near.

I had a boyfriend like this once... ;)

Seriously, though, great article! You've been on a roll lately!
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From:crasch
Date:February 18th, 2003 01:07 pm (UTC)
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Yeah, I know what you mean. I dated an Idaho ground squirrel once. It was always "Where have you been?", "Who was that woman?"...nag, nag, nag.

Even so, I didn't want the relationship to end the way it did. What with the Mack truck bearing down on us, and her just zig-zagging in place...
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From:zapevaj
Date:February 18th, 2003 08:56 am (UTC)
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"When it comes to Homo sapiens, scientists urge us not to read too much into all this."

Humans have this fascinating habit of thinking that, as animals ourselves, where we came from is where we should be, or where we should end up. This is stupid. Even the most barbaric marriages of the Dark Ages look like marital bliss compared to some of the whack-ass shit that nature pulls. We have advanced beyond barbed penii and exploding genitalia, I think; there's no reason to regress.

Speaking of "nature", it also bothers me when people talk about nature as a unitary force, with aims and goals and whatnot. "Nature" is comprised of a bunch of different organisms which have developed a thousand different adaptive mechanisms for survival. Saying that female apes have sex with as many as 8 males in 15 minutes, and implying that that has anything to do with human behavior, is about as intelligent as saying that dung beetles survive quite happily eating shit, and that perhaps that has something to teach us about human nature. In addition, "nature" is not a conscious process; it cannot choose what happens, what happens simply does; it is a purely automatic process that has absolutely nothing to do with morals, ethics, or any sense of right behavior. Fortunately, humans have eventually realized nobler goals than "getting my gametes into as many ch1x0rz as possible". Nature does not have a moral sense, but we do.
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From:perich
Date:February 18th, 2003 09:02 am (UTC)
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Everything you say is true, BUT ... (yeah, ain't that always the way)

How many popular moral codes derive their precepts from "what man was meant to be / do / think"? I'm thinking of the orthodox Christian prohibiiton against homosexuality, which relies on particular views of the proper function of sex, procreation, and lifetime monogamy. Or any social pundit (Marxist, capitalist, take your pick) who asserts that "people aren't meant to live this way."

Expanded knowledge into what it really means to be human, which evolutionary biology can bring us, can help us evaluate and refine these moral precepts.
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From:zapevaj
Date:February 18th, 2003 09:30 am (UTC)
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Here's the thing: -moral- codes, many of which are outdated (such as the admonition against homosexuality), ARE based in evolutionary biology (if only a very ancient and fucked-up version of it)- after all, having sex with anything that can't get pregnant is a waste of valuable sperm, right? (Insert Monty Python song on this topic here.) Same with admonitions against polyandry, masturbation, etc. It's all about maintaining the proper bloodline and knowing which kid belongs to which dad (indeed, in some hard-line patrilineal cultures, if a woman marries and has kids, then is widowed, remarries, and has more kids, the two sets of children are not considered to be related at all. Matrilineal cultures are similar, though they exist less commonly than patrilineal ones.) These are very basic motivations: further your own bloodline, and no one else's.

On the other hand, any social movement that has brought about change- such as capitalism, socialism, or the original European shift from post-Roman-Empire disarray to feudalism- has been motivated by the ethical conscience, not any base motivation. (Okay, so you could argue that it is motivated for a selfish interest in one's own success and that of one's progeny, and that most social revolutionaries fought to better their own situation at the exclusion of everyone else's- but that's different.) The statement "people aren't meant to live this way" implies a concern for human beings in general, not just of your own bloodline, and an ethical sense of justness. After all, even the most violent of Marxist revolutionaries believed that after the revolution (and after we tear the capitalist pig-dogs out of their seats of power and hang them from the streetlamps), there would be equity and security for all. Not just the kids who look like you and not the milkman, but all the kids.

(Pardon the excess parentheticals, I've progressed beyond "too early, not enough coffee" and gotten to "too early, way too much coffee".)
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From:ch
Date:February 18th, 2003 09:16 am (UTC)

Dr. Tatiana's Sex Advice to All Creation

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It is a great book. Clever writing.
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From:springbok1
Date:February 18th, 2003 06:16 pm (UTC)
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I followed a link here and added you as a friend. Your entries are amusing, and we also seem to have a few friends in common.
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From:alpinebutterfly
Date:February 20th, 2003 07:00 pm (UTC)

don't go too far

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just a note from the critical here. This is a good example of an article which argues against exaggerations of something fundamentally true. Its great that it points out that the exaggerations are wrong, but don't let its exuberance in doing so fool you into disbelieving the underlying truth. Lines like:

"The misbegotten idea that males evolved to make love and females to demur gained scientific currency in the late 1940s "

Are taking it too far. The truth is that the fundamental asymmetry of initial parental investment means that males have evolved to make love (more than females) and females to demur (more than males). The fact that females of some species in some environments are promiscuous is consistent with the strong general trend towards guys being sluttier.
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