Sex was the only answer. Total sex.
June 16, 2009 5:33 AM   Subscribe

Has the mystery of sex been explained at last? Biologists have long struggled to explain why most creatures reproduce sexually when they could just clone themselves – now at last it's becoming clear not only why sex evolved, but when. - New Scientist
posted by dgaicun (74 comments total) 9 users marked this as a favorite


 
Ugh, new scientist articles are the worst. If you like evolutionary biology, Carl Zimmer's blog The Loom is a great read.
posted by delmoi at 5:39 AM on June 16, 2009 [8 favorites]


That article is such a great piece of writing. For the audience in question, with that material, it is the perfect thrill. Fuck accuracy, this is how you get people hooked.
posted by krilli at 5:43 AM on June 16, 2009


why sex evolved

It happened, it happened to work, and those species that happened to reproduce sexually were fit enough to continue to reproduce to this very day.

I'm very grumpy about the use of "why" in evolutionary discussions. The proper word is inevitably "how," because evolution doesn't have "reasons," it only has methods. I understand that in layman's terms, you could ask, "why does a giraffe have such a long neck," but it seems so much more accurate to ask, "how did the giraffe evolve to have such a long neck?"
posted by explosion at 5:50 AM on June 16, 2009 [37 favorites]


The rejection of "why questions" by science seems needlessly careful to me. "Why" can ask for either final causes or proximate causes. The latter is perfectly scientific even if the former isn't.
posted by DU at 5:54 AM on June 16, 2009 [2 favorites]


....Personally, any time anyone asked why sex evolved, I've never been able to stop myself from thinking, "who cares why? Let's just be glad it did!"
posted by EmpressCallipygos at 5:55 AM on June 16, 2009 [1 favorite]


The Origin of Love
posted by The Whelk at 5:56 AM on June 16, 2009 [3 favorites]


The rejection of "why questions" by science seems needlessly careful to me.

Under better circumstances, I would agree with you. However, I live in America, a place where a substantial proportion of folks "don't believe in evolution," and many more of those who do believe it was guided by God's hand. In light of this, I would generally prefer serious discussions of science to not sound like a creation myth.
posted by explosion at 6:06 AM on June 16, 2009 [3 favorites]


I'll echo delmoi's comment; Carl Zimmer is just a fantastic science journalist (and I highly recommend his book Parasite Rex). It's a shame that this article, while interesting, was such a slog.
posted by Auden at 6:08 AM on June 16, 2009


explosion: I'm very grumpy about the use of "why" in evolutionary discussions. The proper word is inevitably "how," because evolution doesn't have "reasons," it only has methods.

Ok, in that case the question is 'How did sex evolve when it is so much more complex and costly than simple asexual cloning?'
posted by memebake at 6:09 AM on June 16, 2009


Christ. Wasn't this question answered in high school biology? The advantage sexual reproduction has over asexual reproduction is that with sexual reproduction you end up with a more diverse gene pool. If everything reproduced by cloning there'd be very little variation inbetween members of the same species and thus any type of outside disturbance (whether it be a change in climate or a new virus) would quickly eliminate an entire species.
posted by enamon at 6:11 AM on June 16, 2009 [8 favorites]


"This is known as the Red Queen hypothesis because, like Alice, we have to run fast just to keep up with the ever-changing throng." -from TFA

*wince*

"Well, in our country," said Alice, still panting a little, "you'd generally get to somewhere else — if you run very fast for a long time, as we've been doing."

"A slow sort of country!" said the Queen. "Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!"

New Scientist is a continual stream of cringe-worthy science writing. It's not that they get the Red Queen analogy wrong so much as they completely misplace the sense of it. I don't often go around muttering to myself "I could do a better job than that," but damn if I don't do just that every time I read one of their dumbed-down, wonderless squeezings of science palp.

I, also, do not like why so much as I favor the phrasing, "What is the particular advantage of ..." when it comes to evolution. It is best accompanied by a "what's the hump which must be overcome?" and finally a description of the proposed mechanism and perhaps projections on the rate of diffusion of this advantage throughout the population.
posted by adipocere at 6:18 AM on June 16, 2009 [1 favorite]


enamon: Christ. Wasn't this question answered in high school biology?

No, it's not as simple as that. Although I can't remember why exactly, despite having read The Red Queen by Matt Ridley a few years ago. Its a good book though, gives a lot of entertaining background on the complexities around this issue. Although this new article in NS is basically saying that the eventual theory Matt's book settles on has now been displaced by another one.
posted by memebake at 6:18 AM on June 16, 2009


What's complex & costly about $20?
posted by UbuRoivas at 6:22 AM on June 16, 2009 [6 favorites]


"There is no need for males - a waste of space, as hard-line feminists and evolutionists agree."

I bet someone is fat with a very short hair cut (said in cutesy baby talk).

Hold the phone.... A dude wrote this?!?!?!?!?!

Well I still bet I'm right.
posted by Mastercheddaar at 6:24 AM on June 16, 2009


That article is such a great piece of writing. For the audience in question, with that material, it is the perfect thrill. Fuck accuracy, this is how you get people hooked.

Really? As a piece of literature (nevermind accuracy), I thought it was hackneyed and cliched. Poorly constructed even. What's with the headings on every paragraph?
posted by delmoi at 6:28 AM on June 16, 2009


This is great; New Scientist always has the best and most scientifically rigorous articles that challenge me intellectually. :)
posted by Mirror-Universe Optimus Chyme at 6:33 AM on June 16, 2009 [7 favorites]


enamon: Christ. Wasn't this question answered in high school biology?
For you, maybe. For me it was high school English. Ahhh, Kristi Himmelfahrt where are you now?
posted by Floydd at 6:35 AM on June 16, 2009 [6 favorites]


Kristi Himmelfahrt


This is not a real human person name.
posted by The Whelk at 6:38 AM on June 16, 2009 [19 favorites]


I was going to snark at the "Sex was the only answer. Total sex." part until I saw the poster had beaten me to it.

Note to New Scientist editorial staff: Quality science journalism can not be practiced with two-word sentences.
posted by Joe Beese at 6:39 AM on June 16, 2009 [1 favorite]


Really? As a piece of literature (nevermind accuracy), I thought it was hackneyed and cliched. -- delmoi

I repeat, for the audience in question it is a really well written piece. It's pulp fiction science.
posted by krilli at 6:44 AM on June 16, 2009


I bet someone is fat with a very short hair cut (said in cutesy baby talk).

I bet someone can't think beyond hackneyed and insulting stereotypes to make their... wait, was there even a point to your comment?

Anyway, this part would seem to be the 'meat' of the article:
"Sex improves the efficiency of selection, allowing good genes to recombine away from the junk residing in their genetic backgrounds," says Otto. "As the good genes spread, they then carry along the sex genes, beating out the genes for cloning, and often overcoming the costs of sex."

[...]

[Clones] are particularly vulnerable to high mutation rates, which undermine genetic vigour. Heavy selection puts a premium on the genes that work, and means beneficial mutations are more likely to be selected at the expense of diversity. And diverse populations have the most to lose whenever there's a selective sweep for a particular gene in this way.
posted by teresci at 6:55 AM on June 16, 2009


What's complex & costly about $20?

Same as in town.
posted by jquinby at 7:02 AM on June 16, 2009


Why most creatures reproduce sexually when they could just clone themselves.

Because the first way you get dinner first? Duh?
posted by rokusan at 7:07 AM on June 16, 2009


Christ. Wasn't this question answered in high school biology? The advantage sexual reproduction has over asexual reproduction is that with sexual reproduction you end up with a more diverse gene pool.

Christ, can't you even bother to read the article? It's like you don't even care about the content and all you want to show is that, hey, you went to high school! Good for you.

As you were probably taught at school, the seemingly obvious answer to the question "Why bother with sex?" is that sex generates variation, the raw material for natural selection. As environments change, sexual species can therefore evolve and adapt faster. In reality, though, most individuals live in an environment very similar to that of preceding generations.
posted by splice at 7:07 AM on June 16, 2009 [1 favorite]


Biologists have long struggled to explain why most creatures reproduce sexually when they could just clone themselves

Wait? You mean I went to all that trouble in bars, trying to pick up chicks, for nothing? I could have just cloned myself?
posted by grumblebee at 7:10 AM on June 16, 2009


The biologists I know are mostly concerned with how to clone themselves for sex. They're a fun crowd.

okay fine I don't know any biologists
posted by Navelgazer at 7:26 AM on June 16, 2009


The biologists I know are mostly concerned with how to clone themselves for sex.

"Go Fuck Yourself": Secret Evolutionary Path to Enlightenment?
posted by yeloson at 7:30 AM on June 16, 2009


"Go Fuck Yourself": Secret Evolutionary Path to Enlightenment?


I knew all those guys in khaki drinking identical cocktails at g lounge were onto something!
posted by The Whelk at 7:33 AM on June 16, 2009 [1 favorite]


Most people who go home from bars empty handed, find something to...eh... fill them with. The cloning part doesn't quite work yet, however.
posted by flippant at 7:35 AM on June 16, 2009 [2 favorites]


Makes me wonder what the world would be like if there were only asexual reproduction, if sexual reproduction proved to be evolutionarily unnecessary or disadvantageous. One gender, no attraction, no lust, no "love" (other than companionship)... I think the drive towards social status seeking, to attract "better" mates, would be far less intense. Heck, maybe we would have never evolved past primates, because we'd have nobody to impress!
posted by LordSludge at 7:43 AM on June 16, 2009


Makes me wonder what the world would be like if there were only asexual reproduction

Um, your entire population dies out when a disease no one has protection to pops up?
posted by The Whelk at 7:50 AM on June 16, 2009


Most things made good by one hand are made better by two. Only in art is solitude rewarded.
posted by discountfortunecookie at 8:03 AM on June 16, 2009 [3 favorites]


Um, your entire population dies out when a disease no one has protection to pops up?

Yeah, got it, but I'm thinking that even aside from that pressure, sex drives a lot of progress and development via the desire to attract a more desirable mate. So there's an additional evolutionary advantage to sexual reproduction -- a social advantage.
posted by LordSludge at 8:07 AM on June 16, 2009


"Why so much sex?"

What a gloriously silly article. Thanks.
posted by From Bklyn at 8:11 AM on June 16, 2009 [1 favorite]


Well, bees and ants are social animals that have centralized their repdocutive system, allowing all the sterile members to specialize in some pretty amazing ways.

But then again, you could view social animals like that as a Super Organism, one ant hive is really just one AntMass with lots of separate parts.

Then again, you can also view your body's own specialized systems like that as well. Are you on speaking terms with your lymphatic system?
posted by The Whelk at 8:11 AM on June 16, 2009 [1 favorite]


Does cloning involve an orgasm? 'cause I'd say that's good enough reason right there for sex.
posted by WolfDaddy at 8:23 AM on June 16, 2009


Sex sounds like a really good idea, at first. It's only afterwards, when you're stuck with the 3 AM feeding, that you start to wonder why we bothered with it.
posted by caution live frogs at 8:24 AM on June 16, 2009 [1 favorite]


My understanding is that sexual intercourse began in 1963, between the end of the Chatterley ban and the Beatles first LP.
posted by the quidnunc kid at 8:31 AM on June 16, 2009 [11 favorites]


Also, the OP title may need to replace "Ghostbusters 2" as my go-to smart-ass response to rhetorical questions.
posted by Navelgazer at 8:36 AM on June 16, 2009


And I thought sex was invented in the Sixties. (And so did Philip Larkin.)
posted by kozad at 8:36 AM on June 16, 2009


ahh...the q kid beat me to it!
posted by kozad at 8:37 AM on June 16, 2009


Didn't Michael Keaton already demonstrate why cloning is bad?
posted by orme at 8:44 AM on June 16, 2009


Well, bees and ants are social animals that have centralized their repdocutive system, allowing all the sterile members to specialize in some pretty amazing ways.

Huh, interesting thought, especially considering that the ant/bee system appears to be "better" in terms of sheer numbers of individual organisms it can support -- more resource-efficient than our social sexual system, I suppose.

But does such a system, devoid of Worker Ant A trying to one-up Worker Ant B for the attention and affection of Potential Mate Ant C (with whom they can then reproduce, sharing genes) limit their evolutionary and social/technological progress? (Sorry, "progress" is such a loaded term...) Seems to me this is a key piece of the puzzle in explaining humans' dominance in the animal kingdom. Our system selects for social power, not overall efficiency. Or it would, but for birth control and other modern pressures to keep reproduction low.
posted by LordSludge at 8:48 AM on June 16, 2009


Um, your entire population dies out when a disease no one has protection to pops up?

Not really. Asexual cloning isn't perfect--there would still be some mutation and variation in the population. If even one individual has resistance to the disease, he/she/it would take over all the available resources left be those who got wiped out and quickly repopulate the planet. Lots of organisms evolved to use that route and they're doing fine--bacteria will probably be here long after we're gone.
posted by reformedjerk at 8:51 AM on June 16, 2009 [1 favorite]


I've been trying to clone myself with some frequency since I was about thirteen. No success yet.
posted by Xoebe at 8:51 AM on June 16, 2009 [3 favorites]


"
I bet someone can't think beyond hackneyed and insulting stereotypes to make their... wait, was there even a point to your comment?
"

I was merely reacting to the authors comment on how "Males" are not needed in the world other than to simply reproduce. That somehow we "males' should not be involved in that anymore either because cloning is a better option and sex for the purpose of reproduction should be completely done away with because cloning is better. First thing I thought "wow someone must still be a virgin." I then added the stereotypical fat and short haired comment because being boarderline immature for my age I thought I would add a snarky comment thinking that metafilter could handle it, even perhaps laugh a little inside. If you notice I was not talking about anyone in general but the author of the article. THEN after reading that the author was a man I knew my assessment of him being fat with short hair was probably right. However I think my attempt at snark failed so let me rewrite it as to not upset anyone else:

I bet someone who is obviously a guy (because his name is Nick Lane) does not get enough exercise because he is taking time to write something as complex as a scientific article so through deductive reasoning he is more than likely overweight. Also more than likely he has a shorter hair style due to him being a man and most men have shorter hair than women. His comment about how feminist and evolutionist agreeing that men should not be involved in the reproductive cycle was both hurtful and mean saying my primary reason for existent was flawed. I will end this in a mockingly (Said. In. Cutesy. Baby. Talk).
posted by Mastercheddaar at 9:06 AM on June 16, 2009


Also from Nick Lane:

What's the point of being warm-blooded?
Genetically modified humans (Designer babies!)
The Big O (We breathe Oxygen because it's in the air!)
posted by zennie at 9:10 AM on June 16, 2009


How did sex evolve when it is so much more complex and costly than simple asexual cloning?

You know and I know.
posted by kirkaracha at 9:33 AM on June 16, 2009


Um, your entire population dies out when a disease no one has protection to pops up?

Yeah, and you don't get to have hot decadent last-minute sex as civilization collapses around you either.
posted by Dr Dracator at 9:34 AM on June 16, 2009


I think something got lost in the process of writing this article. Maybe in the attempt to make it more "hip" or engaging. Basically, I find it hard to read, even though I'm very interested in finding out about the subject itself. Here's a sample passage:
When set against this second-rate background, beneficial mutations can wreak havoc. One of two things can happen. Either the spread of the mutation is retarded by the second-rate company it keeps, or it isn't. In the first case, strong positive selection for the gene is dissipated by weak selection against hundreds of others. Such "selective interference" means that most beneficial mutations are simply lost again.

If the new mutation does spread throughout a population, the scenario is even worse. Because the gene can't be isolated from any others, it can only spread at the expense of all other genomes in the population. If 500 variants exist in a population, 499 of them will disappear. So selective interference can portend a disastrous loss of genetic diversity. Much the same thing has happened to the notoriously degenerate male Y chromosome, now a stump of its former self.
If I'm understanding this correctly, this would be a much more readable version of these two paragraphs:
Beneficial mutations can be more problematic in asexual populations. Even if a single gene may offer a large benefit, it may be outweighed by the combined benefit of hundreds of other genes. In that case, the beneficial mutation is lost. However, if the mutation offers a strong enough advantage, it could take over the entire population. In cloning, you can't isolate just the beneficial genes; the entire genome must be copied. So all other variants in the population would end up being replaced.
posted by Deathalicious at 9:58 AM on June 16, 2009 [3 favorites]


Does cloning involve an orgasm?

Have this thundering orgasm, you sexy clone!
posted by CynicalKnight at 10:01 AM on June 16, 2009


As a momentary stop before blowjobs and buttsex.
posted by klangklangston at 10:03 AM on June 16, 2009


I was merely reacting to the authors comment on how "Males" are not needed in the world other than to simply reproduce. That somehow we "males' should not be involved in that anymore either because cloning is a better option and sex for the purpose of reproduction should be completely done away with because cloning is better.

The author wasn't speaking politically, he was speaking biologically, you pinhead. He wasn't saying, "men are useless", he was saying, "biologically, it's not clear why we evolved the need for a separate gender that was male". And you know, if it weren't for men, there'd be no such thing as women either. There'd just be genderless people. So if the statement was anything, it was genderist, not sexist.

He wasn't speaking aspirationally, either. He wasn't saying, "oh, if only we could clone, it would be so much better".

Let's think about this: for a fair number of species, the reproductive process is so time and energy consuming that once they are done with it, one or both of the genders die instantly. In that context, yes cloning is a whole lot better. If human reproduction required so much energy that an outcome of having a baby was an 80% chance of death for one or both partners you'd better believe that our scientists would be working day and night for cloning options.

You can go on believing that someone interested in science is fat and ugly, and that he is trying to hurt you by stating biological truths. Or you can stretch your brain just a tiny bit and try to really understand what someone is saying before making broadly stupid assumptions.
posted by Deathalicious at 10:14 AM on June 16, 2009 [1 favorite]


orme: Didn't Michael Keaton already demonstrate why cloning is bad?

He was really only following up more advanced research that had already been done in numerous episodes of Star Trek.
posted by koeselitz at 10:15 AM on June 16, 2009


Adaptation wins out in the long run. Story at 11.
posted by Avelwood at 10:18 AM on June 16, 2009


The Whelk: This is not a real human person name.
That would not have been the only thing she lied about.

*sniff*
posted by Floydd at 11:08 AM on June 16, 2009


Deathalicious: The author wasn't speaking politically, he was speaking biologically, you pinhead. He wasn't saying, "men are useless", he was saying, "biologically, it's not clear why we evolved the need for a separate gender that was male".

Not precisely. The quotation in question was:

from article: There is no need for males - a waste of space, as hard-line feminists and evolutionists agree.

Erm, yes, he's sort of making the argument you say he is. He's also being what we call “a cheeky monkey” and making an annoying political joke about “hard-line feminists.”

You can go on believing that someone interested in science is fat and ugly, and that he is trying to hurt you by stating biological truths. Or you can stretch your brain just a tiny bit and try to really understand what someone is saying before making broadly stupid assumptions.

Okay, well, I don't know if it's as simple as all that.

No, seriously, I don't know if it's as simple as all that; it might well be, but MasterCheddaar isn't really making any damned sense, so I haven't a clue. I'm thinking he (a) didn't read the article and (b) made what I personally take to be a borderline insensitive (or ridiculous, I can't tell) assumption about gender.

from article: There is no need for males - a waste of space, as hard-line feminists and evolutionists agree.

Mastercheddaar: I bet someone is fat with a very short hair cut (said in cutesy baby talk).

Hold the phone.... A dude wrote this?!?!?!?!?!

Well I still bet I'm right.


Now, in my bafflement, I've tried saying “I bet someone is fat with a very short hair cut” in cutesy baby talk about nine times now, and it still doesn't really make sense to me. Taking MasterCheddaar's surprise that the author is “a dude” into account, however, he is joking that he assumed that a fat woman with a very short haircut wrote this article; and, racking my brain, the only thing I can think is that this is MasterCheddaar's stereotype of lesbian women and/or the aforementioned “hard-line feminists.”

Okay, so, first of all, this doesn't make any sense. Why? Because the author isn't claiming that males are useless—as you would have seen if you'd read, say, the next two paragraphs, MasterCheddaar, the author mentions that males seem to be useless from a biological perspective in order to set up the question: why is there sex? He's not making a statement of intrinsic worth. You say later that

Mastercheddaar: His comment about how feminist and evolutionist agreeing that men should not be involved in the reproductive cycle was both hurtful and mean saying my primary reason for existent was flawed.

…by which I assume you mean one of two things: that (a) maleness is your “primary reason for existen[ce]” because you were born through male/female sexual reproduction; or that (b) you yourself are involved in fatherhood, and see this fatherhood as your “primary reason for existen[ce].” But in either case, I would argue that you're wrong; you could very well have been cloned rather than sexually produced, and even if your offspring are a great joy to you, can you honestly say with confidence that clone-produced offspring wouldn't mean much to you?

At the heart of it, your mistake in reading this article is this: you imputed to the author opinions which he is merely describing. He doesn't say that he is one of those evolutionary biologists or one of those so-called hard-line feminists; in fact, he is neither.

Which brings me to my next point: second of all, your comment makes an annoying inference in that it engages in pointless and insensitive stereotyping. In fact, you so greatly misread this sentence in the article that you appear to have missed what, to me, was an annoying stereotype that the author uses here. He tosses in “hard-line feminists” as a sort of a joke: since, haw haw, everybody knows that hard-line feminists wish there were no men, right? I find this joke a bit stupid, and if I were more PC, I'd even say that it's offensive. Why? Because it's a pretty stupid false generalization. I've met some pretty hard-line feminists, some very angry women with whom I probably will never agree, and yet not one of them has ever once suggested to me that men should not exist. I guess maybe there are people in the world somewhere who believe that, but I haven't met them; as it is, this little joke, as small and seemingly harmless as it may appear, belittles feminism by speaking of it as mere male-bashing.

You weren't content to leave that annoying stereotype be, but apparently felt that it was your duty to make it even more offensive by appending fat and short-haired to man-bashing as supposed hallmarks of feminism. I assure you that, while I know a lot of feminists and consider myself one, and while I also know a few so-called ‘hard-line’ feminists, I have never met a feminist who was short-haired and overweight.’ Not only is this stereotype statistically wrong; it's ludicrous. For that reason, it's hardly even offensive anymore; it would be like saying that all Jews prefer bacon over honey-baked ham—just stupid.

Anyhow, I've spent far too much time responding to something that probably didn't need responding.

posted by koeselitz at 11:18 AM on June 16, 2009 [2 favorites]


"Sex improves the efficiency of selection, allowing good genes to recombine away from the junk residing in their genetic backgrounds," says Otto.

I thought the recombination has long been the explanation for the widespread evolution of sexual reproduction. I guess I'm missing the "new" part of this finding. Or is it that simulations now bear out quantitatively what has long been theorized?
posted by Mental Wimp at 11:38 AM on June 16, 2009


Ah! I'd meant to say:

If you want to read a veritable classic science-fiction short story that deals with some of the issues we're talking about here, you should go to your library and look up ‘James Tiptree, Jr's’ short story “Houston, Houston, Do You Read.” ‘James Tiptree, Jr’ actually turned out to be a pseudonym for a woman named Alice Sheldon; Sheldon, a bisexual doctor of experimental psychology who'd worked in the Photointelligence Group in the Army Air Corps and whom the CIA had tried (unsuccessfully) to recruit, said later:

“A male name seemed like good camouflage. I had the feeling that a man would slip by less observed. I've had too many experiences in my life of being the first woman in some damned occupation.”

“Houston, Houston, Do You Read” is a frightening and depressing little story (at least for us males) about a crew of male astronauts who accidently get shot forward in time several centuries to a time when all males have been wiped out by an epidemic, and the only survivors, a few million women, reproduce exclusively by cloning. What's frightening and depressing about the story is that the author very convincingly depicts males as both boorish in their essential natures and generally unnecessary to the world of the future. But it's a great story nonetheless; the fact is that Sheldon understood as few sci-fi writers seem to (even amongst the women) that the world of women is a bright, lively, interesting place—not the cold, frightening Amazonian nightmare men sometimes liked to imagine in science fiction stories.

Sheldon's stories often were quite interesting deconstructions of sexist tropes. Another classic of hers is “The Women Men Don't See,” wherein a man tries to rescue some women from alien abduction only to discover that the women don't want to be rescued—they want to be abducted so that they can leave earth, since this planet offers so few opportunities for a creative or thoughtful woman.
posted by koeselitz at 11:40 AM on June 16, 2009 [3 favorites]


Lots of organisms evolved to use that route and they're doing fine--bacteria will probably be here long after we're gone.

Yah but Microorganisms are WEIRD. Like at that level, you can get exciting new genetic material by eating something or getting attacked or crashing into someone or getting absorbed and becoming thier semi-independent organelle. Sure they reproduce asexually, but the churn of new/mixed/random/mutated DNA is on a much higher and faster level. When I said "everyone dies!" I was thinking more like Bananna blight (but then again, that was an artificially created sterilization, so ...there)
posted by The Whelk at 11:41 AM on June 16, 2009


Sex was the only answer. Total sex.

Oh dear lord.
posted by nebulawindphone at 12:07 PM on June 16, 2009 [1 favorite]


The issue isn't just explaining why almost all plants and animals engage in sex. It is also explaining why the life forms that ruled the planet for billions of years and remain by far the most abundant - the bacteria - manage fine without it.
...
Dacks, for example, hedges his bets. "I am not entirely convinced that introns necessarily came from mitochondria, given that bacteria pass around their genes a lot today, although they certainly could have."

The claim that bacteria exclusively practice some type of staid linear chain of genetic descent has been pretty thoroughly debunked by this point. Bacteria have numerous methods of merging foreign DNA into their own genomes and getting rid of the unadvantagous genes. They aren't even limited to getting DNA from the same species. The latest maps of Archean homology (mapping which swatch of DNA came from where) do not look like a top down tree of life. It looks like a gigantic mess of spaghetti, with multiple contributors to any one bacterial genome.
posted by benzenedream at 12:08 PM on June 16, 2009


Ha! Hello, title.
posted by nebulawindphone at 12:09 PM on June 16, 2009


"why sex evolved"

Once the bass riff started it was inevitable.
posted by Smedleyman at 12:28 PM on June 16, 2009 [1 favorite]


Wow I love it when people look WAAAAAAAY too deeply into something I say here meant to be me just being a dick. If you want me to get into just the article then I will.

Cloning a single cell organism might work for them. They are fairly simple creatures and not a whole lot can go wrong with them. Cloning is stupid for something as complex as a human being. It is not a good way to keep a species going for the long run. Take me for example I have a bad knee. It is genetic. My grandpa, uncles, aunts all have bad knees. In fact their original eastern European name means bad knees. I cannot for long periods of time train on it by running miles every day without it hurting me. My clone would have the same problems as I do right now. I have cousins that do not have bad knees. The trait was bred out of them. The same can be said for people with poor eye sight. I have excellent eye sight. So this is when you combine my 20/20 vision with someone with good knees. Grant it that you might end up with a poor eye sight bad kneed off spring but you also might end up with someone who has better eyes and knees. Whereas if I had just cloned myself I would be stuck with someone just like me with bad knees. So sexual reproduction equals a chance for something greater or something worse. Survival of the fittest comes to mind here. Future generations will have better knees and eyes. On the flip side if I cloned myself over and over for the same amount of generations nothing will change. The author suggested that cloning is better than sexual reproduction. I fail to see how and so I made fun of it.

Tada there you have it. My take on this article.

As for the previous comments and stereotypical remarks that is me being a dick. If I am the only dick you come across for the remainder of the week then consider yourselves lucky.
posted by Mastercheddaar at 12:35 PM on June 16, 2009


Because "hey baby, you want to go home and mutually clone ourselves" is sooo much less fun.
posted by clearly at 12:51 PM on June 16, 2009


Well, no the problem of sex hasn't really been satisfactorally answered (there is still a bunch of current research on it, including my current PhD work).

The "males are useless" argument is a pop science phrasing of the two fold cost of sex. This basically says that in anisogamous (ie male and female) species a female that clones rather than mates can produce two identical female offspring which can each produce two offspring which produce 4 etc etc, so doubling in number every generation. The sexual female produces a male and a female, which both need to mate, producing a net of two offspring (each only sharing half the parents genes) every generation, so no doubling.

So, when there is no parental care (and a bunch of other assumptions), the asexual clones leave twice as many offspring, which is a pretty massive benefit to them. There are some problems with the idea, and a bunch of other costs too, eg, but this is the most widely cited and highest cost.

To say that sex causes variation is correct, but having variable offspring isn't really as good as having twice the number of offspring. There are a bunch of theories which try and explain how the variation can lead to a greater gain of fitness - see wikipedia but none are really convincing without experimental data.

The article itself appear to conflate three claims: Sex was present in the Eukaryotic common ancestor (probably true). Sex arose as the consequenct of genetic conflict between mitochondria and nuclear genomes (pretty controversial, I wouldn't agree). A brief very simplified explanation of Otto's "abandon ship hypothesis" (interesting, but just because the math works, doesn't mean that's how biology does).
posted by scodger at 12:59 PM on June 16, 2009 [2 favorites]


Mastercheddaar: As for the previous comments and stereotypical remarks that is me being a dick. If I am the only dick you come across for the remainder of the week then consider yourselves lucky.

*sigh*…fair enough, I guess.
posted by koeselitz at 1:00 PM on June 16, 2009


The Whelk: Are you on speaking terms with your lymphatic system?

We don't speak directly, but it's constantly leaving nodes all over my body for me to read.
posted by Greg_Ace at 1:04 PM on June 16, 2009 [1 favorite]


Okay, I skimmed both the article and the incredibly derailed thread, but if anyone's wondering why the high school explanation doesn't make sense, it's because the unit of evolution that it's usually most parsimonious to study is not the individual (or the species! wut) but the gene. You can study evolution in terms of the individual and also even in terms of the species, but with rare exceptions it is far more profitable in a power-of-explanation sense to study evolution in terms of genes. (Or allelles or some shit but it's been a few years.)

So, it doesn't make a lot of sense for a gene to engage in a process (sex) in which it only has a 50% chance of passing itself on, when theoretically there was the alternative of cloning, which has closer to a 100% chance of passing itself on. Sex is a method of reproduction that is about twice as lethal to genes as cloning. That's why it's a mystery to biologists.

Of course, the “explanation” is It happened, it happened to work, and those species that happened to reproduce sexually were fit enough to continue to reproduce to this very day, but that doesn't satisfy most people.

As I say, it's been a few years, so if I've muddled this feel free to correct me.

Key text: Dawkins' The Selfish Gene (1976), though my long-winded opening paragraph is a more contemporary viewpoint.
posted by skwt at 1:31 PM on June 16, 2009


As for the previous comments and stereotypical remarks that is me being a dick. If I am the only dick you come across for the remainder of the week then consider yourselves lucky.

If you can acknowledge that your behavior and commentary is dickish, knock it the fuck off!

Not every conversation on this site requires input from every reader. If you don't have something constructive to say, don't speak up. I don't mean to discourage lurkers from chiming in, but there's no reason to say something if you don't have something constructive to say.

The Internet is surprisingly like real life, to be honest. If people are having a nice conversation, yelling over them is rude. Changing the topic of conversation is rude. If you have to start your commentary with, "I don't want to sound racist, but...", you will sound racist. If you start with, "No offense, but...", your audience will probably take offense.

One great thing about Metafilter is that we have to push that "Post Comment" button before we really put our feet in our mouths. If you think you're posting something dickish, back off for a second, re-read what you wrote, and if you can't find a way to say it nicely, maybe just don't comment. This goes double for AskMe, where anything that isn't a direct helpful answer to the question is frowned-upon.
posted by explosion at 1:43 PM on June 16, 2009 [4 favorites]


What's with the headings on every paragraph?

A peculiar British thing, if I may be so bold to speak as an Australian. Viz magazine takes the piss out of this perfectly, if you ever happen across a copy. As the [satirical] article progresses the headings get more and more obscure and tangential.
posted by uncanny hengeman at 7:38 PM on June 16, 2009 [1 favorite]




I've always imagined sexual reproduction was advantageous to multicellular organisms because it improves a population's genetic capacity for adaptation. Gametes effectively front-load natural selection against mutations fatal at the cellular level. And maybe something about multiple copies of chromosomes keeping mutations around for long enough to create something new and interesting. I assume this not a new theory to biologists.
posted by pwnguin at 7:48 PM on June 16, 2009


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