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  #1  
Old 02-14-2009, 02:19 AM
Bloggingheads Bloggingheads is offline
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Default Science Saturday: Darwin the Rock Star

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  #2  
Old 02-14-2009, 02:34 AM
Happy Hominid Happy Hominid is offline
 
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Default Re: Science Saturday: Or Science Friday Night

Here on the West Coast, anyway. But that's cool. Nothing better to do...
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  #3  
Old 02-14-2009, 03:08 AM
claymisher claymisher is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Overrated?! Underrated! Darwin would be famous just for his soil science alone.
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  #4  
Old 02-14-2009, 05:04 AM
StillmanThomas StillmanThomas is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

A superb conversation!!!

John does a masterful job of drawing out Carl's clarity and eloquence. Thanks to both of you for a sterling effort.
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  #5  
Old 02-14-2009, 09:43 AM
bwn bwn is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

It's interesting how horizontal evolution seems to validate the logic of some ritual cannibalism: eat another person in order to take on his attributes. I wonder what the odds are that the DNA eaten by a cannibal would get incorporated into his own DNA and benefit him, or that it would be passed on to his offspring. I'm sure they're minuscule, but it's interesting that there is any chance at all of it happening.
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  #6  
Old 02-14-2009, 10:08 AM
AemJeff AemJeff is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by bwn View Post
It's interesting how horizontal evolution seems to validate the logic of some ritual cannibalism: eat another person in order to take on his attributes. I wonder what the odds are that the DNA eaten by a cannibal would get incorporated into his own DNA and benefit him, or that it would be passed on to his offspring. I'm sure they're minuscule, but it's interesting that there is any chance at all of it happening.
I think Carl answered that pretty clearly - it's hard to imagine a path for an intact DNA molecule to take from the digestive system to the gonads. I'd bet that a viral infection (maybe bacterial?) is about the only open path available.
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  #7  
Old 02-14-2009, 11:10 AM
bjkeefe bjkeefe is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by Bokonon View Post
A superb conversation!!!

John does a masterful job of drawing out Carl's clarity and eloquence. Thanks to both of you for a sterling effort.
I couldn't agree more. What a perfect way to mark Darwin's birthday. I think Carl and John struck exactly the right note -- there's no need to elevate Darwin beyond his many real accomplishments and contributions, but at the same time, his birthday anniversary is a good occasion to reflect on everything that has happened since.
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  #8  
Old 02-14-2009, 01:42 PM
bbenzon bbenzon is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Yes, a great conversation.

Nowhere is the over-evalulation of Darwin more evident than in so-called Darwinian literary criticism, which is mostly about evolutionary psychology, but so far has shown little interest in the multiplicity of literary forms and their historical evolution.
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  #9  
Old 02-14-2009, 02:31 PM
uncle ebeneezer uncle ebeneezer is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

I'm only 25 minutes in, but yeah, this is definitely a keeper. Cool to hear Carl be interviewed, for a change.

Although shouldn't this have been titled "An R-rated Bloggingheads" to try and drive up hits?
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  #10  
Old 02-14-2009, 03:10 PM
thprop thprop is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by uncle ebeneezer View Post
I'm only 25 minutes in, but yeah, this is definitely a keeper. Cool to hear Carl be interviewed, for a change.
Actually, Carl has been interviewed twice before on BHtv. His first appearance with John Horgan back on Sept 28, 2007.

He then was an occasional host of Science Saturday but was a guest again on May 16, 2008, when George Johnson talked to him about his book Microcosm - which you all should have read by now.
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  #11  
Old 02-14-2009, 03:41 PM
uncle ebeneezer uncle ebeneezer is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Thprop, yeah I saw those, as well. I just meant that usually he serves more as the interviewer role picking some interesting scientist's brain, so it's always cool when we get a chance to pick his brain.
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  #12  
Old 02-14-2009, 03:47 PM
ed fielding ed fielding is offline
 
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Default Re: Science Saturday: Darwin the Rock/ Star

Rich and satisfying brain food.
And touching upon some issues that have intrigued me for a long time.

The bacterial Gaia. Sonea and Panniset in A New Bacteriology (1980; trans. 1983) wrote of a half-dozen means of genetic transference among microbes, information transfer.
I have to go back and reread it; notice now in the table of contents “Bacterial Cooperation at the Continental or Planetary Level”.
Lynn Margulis (collaborated with James Lovelock on the Gaia hypothesis and was a pioneer in the idea that cooperation is the leading dynamic in evolution, rather than competition) wrote its Foreward, where she says “Small replicons are passed among bacteria with the rapidity and fluidity we associate with with international telephone calls and transoceanic cables...their communications system forms a worldwide network.”
Putting this together with all manner of research appearing since then, (long pre-web, obviously) for example the depth at which bacteria are found beneath the earth, and the then unimagined potentials of computation for distribution of information, leads to a suggestion that in fact bacterial life composes a global super-computer dwarfing the most exoptic envisionings of computer scientists I’ve come across.
That is also to say that bacterial intelligence, ubiquitous and pervasive reaching far beyond what or where humans have achieved or imagined, is a force, whose surface we have only scratched in spots.
Further, taking from Read Montague in Your Brain is (Almost) Perfect (2007) the argument that valuation occurs in all organisms, balancing reward against its cost in energy (which Carl touches on lightly) to promote survival and drive adaptation and development; a force to guide the computations of this planetary computer is integral to its function, and evolution is the outcome of macromicrobial decisions regarding value, cooperating with mounting degrees of collaborative complexity: By this reading human culture (and all others) is one of many algorithms running on the Mother of all Supercomputers.

The white mice running the experiment? Being run by the Computer.
That’s the riff: It displays the weakness of riffs, a suggestion not a definition, and lacking Carl’s (and my) preference for attending to complexity and nuance, reducing, reducing, and blindly neglecting other determinative issues.I would be appalled (if unsurprised) if the Supercomputer was taken to be another God substitute. But as a riff I’ve been rattling off for twenty-five years, I have yet to see these connections made explicitly.

If Carl sees fit, since he seems an ideally informed commenter here, I’d be delighted to hear his reaction to such an admittedly extreme suggestion.

And many thanks for a fittingly outstanding diavlog.
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  #13  
Old 02-14-2009, 04:00 PM
nkirby nkirby is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Oh, science, how romantic! (Is this sarcasm also disallowed?)
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  #14  
Old 02-14-2009, 04:07 PM
bjkeefe bjkeefe is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by uncle ebeneezer View Post
Although shouldn't this have been titled "An R-rated Bloggingheads" to try and drive up hits?
LOL.

Even better: An R-rated Bloggingheads in Which Ann Coulter is Discussed. And Also: Sex.

Though to deal with the squeamish, you might have to make extra-clear that the two were not coincident.
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  #15  
Old 02-14-2009, 05:22 PM
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Default Re: Science Saturday: Darwin the Rock Star

When you are ready to advance from bacteria:

http://www.protomag.com/assets/a-mighty-worm

http://www.wormbook.org/

http://www.wormatlas.org/
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  #16  
Old 02-14-2009, 05:24 PM
jhorgan@highlands.co jhorgan@highlands.co is offline
 
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Default Critique of Carl on intelligence

Hi folks: I'd like to share comments that a friend emailed me re Carl's discussion of intelligence:

Why does Zimmer (or whoever did the experiments) equate superior sense of smell in the flies with "smartness"? Maybe it was their exaggerated sense of smell that killed them - overwhelming them when confronted with what was it? a carcass or something - the food source. You know, like an autistic experience, or like a migraine, or how Van Gogh saw colors - know what I mean? It equates smartness with an unbalanced oversensitivity, sort of. We all know one of the burdens of any sensitivity is having to learn to control it and without the control it's not "smart" but crazy, or at least a weakness. It makes me think of those Temple Grandin books. Also, the timing of forcing evolution like that could be too fast. If I'm going to develop a superpower, I don't want it coming on me all at once, I want it to come little by little so I can learn to adjust to living with it.
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  #17  
Old 02-14-2009, 06:38 PM
AemJeff AemJeff is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by thprop View Post
George Johnson talked to him about his book Microcosm - which you all should have read by now.
Just wanted to add a "yup" to that. Microcosm was one of the two or three best books I came across year.
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  #18  
Old 02-14-2009, 06:40 PM
AemJeff AemJeff is offline
 
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Default Re: Critique of Carl on intelligence

Quote:
Originally Posted by jhorgan@highlands.co View Post
Hi folks: I'd like to share comments that a friend emailed me re Carl's discussion of intelligence:

Why does Zimmer (or whoever did the experiments) equate superior sense of smell in the flies with "smartness"? Maybe it was their exaggerated sense of smell that killed them - overwhelming them when confronted with what was it? a carcass or something - the food source. You know, like an autistic experience, or like a migraine, or how Van Gogh saw colors - know what I mean? It equates smartness with an unbalanced oversensitivity, sort of. We all know one of the burdens of any sensitivity is having to learn to control it and without the control it's not "smart" but crazy, or at least a weakness. It makes me think of those Temple Grandin books. Also, the timing of forcing evolution like that could be too fast. If I'm going to develop a superpower, I don't want it coming on me all at once, I want it to come little by little so I can learn to adjust to living with it.
It sounded to me like the increase was in discrimination, and that, I think, is an excellent proxy for "intelligence." It would be interesting to know more details about the study.
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  #19  
Old 02-14-2009, 07:58 PM
uncle ebeneezer uncle ebeneezer is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Agreed. I got a little side-tracked during the middle portion so it took me a little longer than I expected, but it was a really great book.
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  #20  
Old 02-14-2009, 08:15 PM
hurt hurt is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Wait a second, I definitely read about inherited HIV somewhere. Anyone have any good links on this?
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  #21  
Old 02-14-2009, 08:28 PM
AemJeff AemJeff is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

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Originally Posted by hurt View Post
Wait a second, I definitely read about inherited HIV somewhere. Anyone have any good links on this?
I think "inheritance" in this sense doesn't mean literal genetic inheritance. (An HIV infected father wouldn't pass the disease as a trait.) More Likely it's about transfer of the virus from mother to child. The following seems to me to help clarify the context of your question:

Quote:
When an infant is born to an HIV-infected mother, diagnosis of an HIV infection is complicated by the presence of maternal anti-HIV IgG antibody, which crosses the placenta to the fetus. Indeed, virtually all children born to HIV-infected mothers are HIV-antibody positive at birth, although only 15%-30% are actually infected.

(source)
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  #22  
Old 02-14-2009, 11:11 PM
hurt hurt is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Thanks AemJeff. That makes a lot of sense.

As far as IQ scores growing over the past 100 years, one easy factor to point out is better nutrition, which presumably would help fetal development of whatever factors induce intelligence. I know that famines produce abnormally large litters of autistic children and perhaps children with other mental disorders (but what about the uptick in autism in the U.S.?)

Also, knowledge about health has grown immensely--we now know that drinking during pregnancy is harmful to the fetus (a little more than a hundred years ago people might still have been drinking fermented water as a safe alternative to contaminated water, or maybe this had been largely discontinued).

I don't know how much these fetal problems lead to genetic changes or simply problems with expression of present genes, or what the difference is. I guess I'd better buff up on this, because it is really interesting.

Much of the explanation must be cultural (more time to learn and go to school, more democratic knowledge dispersion) but one cannot deny the biology that allowed us to reach these cultural "heights".
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  #23  
Old 02-15-2009, 02:11 AM
Nate Nate is offline
 
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Default Bill Gates releasing mosquitoes

The release of mosquitoes by Bill Gates at TED, which Carl talks about can be viewed in its entirety on the TED site. (The mosquitoes are not the most important or interesting part of the talk, in my opinion.)
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  #24  
Old 02-15-2009, 05:52 AM
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Default Re: Science Saturday: Darwin the Rock Star

Enlightening dialogue. Could I make a suggestion, though, about vocabulary?

It seems to me that certain aspects of what we call "culture" today could be called something else, with great gains to clarity and scientific precision. This is something of a hobbyhorse of mine and probably a lost cause but I am always aghast when I hear people talk of culture as if it were nothing but education, learned behavior, or tradition---in short, something superadded to our evolutionary inheritance that has made us better, or in any case superior to other animals. This definition of culture has two disadvantages: it omits all those aspects of education and tradition that have made us worse than animals---what Freud called das Unbehagen in der Kultur (i.e. superstition and the exacerbation of aggression through the human institution of war)---and it postulates that as we learn more as a species we "progress," morally and politically. The evidence for progress in either sense, is, to say the least, not overwhelming.

William James and other nineteenth-century psychologists, writing in the wake of Darwin, often used another category, halfway between nature and culture, that of habit or custom. May I suggest that instead of always speaking of culture, we think sometimes in terms of habits, which, as we all know, can be both good and bad?
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  #25  
Old 02-15-2009, 11:30 AM
Carl Zimmer Carl Zimmer is offline
 
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Default Re: Critique of Carl on intelligence

Hi folks--Glad to see that people have enjoyed the diavlog. I'm not surprised that some of my remarks ended up being a bit cryptic and generated some questions like this one--

Quote:
Originally Posted by jhorgan@highlands.co View Post
Hi folks: I'd like to share comments that a friend emailed me re Carl's discussion of intelligence:

Why does Zimmer (or whoever did the experiments) equate superior sense of smell in the flies with "smartness"? Maybe it was their exaggerated sense of smell that killed them - overwhelming them when confronted with what was it? a carcass or something - the food source. You know, like an autistic experience, or like a migraine, or how Van Gogh saw colors - know what I mean? It equates smartness with an unbalanced oversensitivity, sort of. We all know one of the burdens of any sensitivity is having to learn to control it and without the control it's not "smart" but crazy, or at least a weakness. It makes me think of those Temple Grandin books. Also, the timing of forcing evolution like that could be too fast. If I'm going to develop a superpower, I don't want it coming on me all at once, I want it to come little by little so I can learn to adjust to living with it.
These experiments were not selecting simply for smell. In fact, the experiments were carefully designed to avoid doing just that. The flies instead were selected on their basis of how quickly they could learn to associate an arbitrary smell with the presence of quinine, a nasty-tasting substance if you're a fly. While there's a lot that goes into intelligence as we think of it in humans, this sort of learning is still one important element. Here's an article I wrote on this research in the Times, and here's a google scholar page of the relevant papers.
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  #26  
Old 02-15-2009, 04:09 PM
Titstorm Titstorm is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

absolutely fantastic section on bonobos/chimps. thanks, Carl.

holy crap! even better was the section on group selection. this is one of the best science saturdays ever. i'd probably have to put it in the top five.

Last edited by Titstorm; 02-15-2009 at 04:19 PM..
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  #27  
Old 02-15-2009, 09:21 PM
Wonderment Wonderment is offline
 
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Default Quibble and Kudos

One quibble: Carl cited our common ancestor with bonobos and chimps at 2 million years; it's more like 6 million, from what I've read.

But it was a great broad-ranging conversation. Kudos to John and Carl.
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  #28  
Old 02-16-2009, 02:29 AM
Eastwest Eastwest is offline
 
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Default Carl Zimmer Rocks!

Wow!

Carl Zimmer just gets better and better every time I watch / listen to him here. He really should be a regular & I think John Horgan is his perfect pairing for bringing out the best.

I just love it when CZ becomes a little more free in expressing critical opinions and when he starts to turn loose his obviously rich sense of wry humor.

Merci beaucoup & please do come back!

EW
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  #29  
Old 02-17-2009, 04:37 PM
Me&theboys Me&theboys is offline
 
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Default Group Selection

I am a skeptic about group selection, but would be happy be be persuaded otherwise. I think the concept continues to receive a lot of support in large part because of two factors: 1) it's a shape-shifter whose definition changes in the face of data that does not support it; 2) it makes people feel good about evolution because of its association with behavior that has "pure" altruistic motives.

As to the first, it would have been helpful if group selection had been defined at the outset of the conversation and if some links to the material Carl referenced had been posted. Here is a pretty good definition of group selection from Wikipedia: "the idea that alleles can become fixed or spread in a population because of the benefits they bestow on groups, regardless of the alleles' effect on the fitness of individuals [and their genes] within that group". The most important part of that definition is the latter part. Without that, group selection could just be an "emergent phenomenon" of natural selection and not a fundamental mechanism of evolution itself. It's hard to know what version of group selection Carl and John were talking about. I would be most interested to hear about work which demonstrates group selection that meets the above definition. The behavior of bacterial groups whose members are genetically identical would not quality.

As to the second, altruism has already been explained via natural selection. People just don't like its selfish origins. But there is nothing inherently warm and fuzzy about group selection. Altruism via group selection is no less grim. Group selection implies altruism to non-kin within a group; it also implies the opposite to non-kin outside a group, which leads us to the age old Us/Them mentality, which is the basis for war, group violence, exploitation, and other serious problems. One rarely hears or reads about the dark side of group selection. Why is that?
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  #30  
Old 02-17-2009, 05:04 PM
bjkeefe bjkeefe is offline
 
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Default Re: Group Selection

Quote:
Originally Posted by Me&theboys View Post
[...]
On a somewhat related note, did you see this?
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  #31  
Old 02-18-2009, 12:42 PM
Carl Zimmer Carl Zimmer is offline
 
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Default Re: Quibble and Kudos

It's Carl again. The common ancestor of bonobos and chimpanzees lived 2 million years ago. The common ancestor of bonobos, chimps, and us, lived about 7 million years ago. (For more: http://www.plosgenetics.org/article/...l.pgen.0030066 )
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  #32  
Old 02-18-2009, 05:06 PM
Alexandrite Alexandrite is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by AemJeff View Post
I think "inheritance" in this sense doesn't mean literal genetic inheritance. (An HIV infected father wouldn't pass the disease as a trait.) More Likely it's about transfer of the virus from mother to child. The following seems to me to help clarify the context of your question:
Retroviruses, such as AIDS, have been shown to affect the gametes, allowing the virus to pass on genetic material to the host's descendants. Most of this material ends up as junk in your dna. The influence of Viruses on evolution is a new subject, there was a lengthy article on it a few months back but I forget the publication. By studying this DNA we've been able to identify where retroviruses have hit human ancestors in the past and how we've evolved immunities for those.

Carl, I think you give to little credence to the "we're not evolving" crowd. The gained immunity to a virus is minor, and they wouldn't argue with that. A more specific argument they would have would be that human speciation has stopped. Here are some of the reasons:
The human race is a large and stable, this weakens the possibilities for genetic drift and weakens the probability of rapid evolution.
The human race's sexual selection is pretty random and while not homogeneous across our entire population, even amongst the most harsh geographic constraints genetic material is able to pass between all human groups.
All of our negative and positive aspects by which we select are predominately based on a learned experience, rather then a better genetic adaption to fit our environments. We don't deny people with bad genes the right to reproduce. And what determines success or failure of a person in society or biologically isn't based on genetics, there is no survival-of-the-fittest super genes amongst our wealthy and powerful that are getting selected for to make them more wealthy or powerful. We depend far to much on culture.

I think it's safe to say that if we are evolving, it's happening far to slowly to be relevant compared to culture. Yes, maybe in a few hundred years people might be born with higher resistances to AIDs, but hopefully we'd have a cure for that by then. And as long as we keep developing tools to fight the environmental changes rather then letting nature do her course, superior adaptations aren't going to be relevant or selected upon in our pool.

Besides that it was a good discussion. I too had a bit of Darwin/Lincoln fatigue by the end of last week.
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  #33  
Old 02-18-2009, 05:15 PM
Wonderment Wonderment is offline
 
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Default Re: Quibble and Kudos

Thanks for clearing that up, Carl. I got confused over "the" common ancestor and "our" common ancestor. My bad.
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  #34  
Old 02-18-2009, 05:33 PM
AemJeff AemJeff is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by Alexandrite View Post
Retroviruses, such as AIDS, have been shown to affect the gametes, allowing the virus to pass on genetic material to the host's descendants. Most of this material ends up as junk in your dna. The influence of Viruses on evolution is a new subject, there was a lengthy article on it a few months back but I forget the publication. By studying this DNA we've been able to identify where retroviruses have hit human ancestors in the past and how we've evolved immunities for those.
If you do happen to recall where you saw that article, please post it here. That's fascinating.
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  #35  
Old 02-18-2009, 06:27 PM
Alexandrite Alexandrite is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

It might have been This one that I was thinking of, though I don't know where I read the gamete thing. I'm mistaken HIV isn't an "Endogenous Lentivirus" as the term goes, but it could become one.
edit: Here is a wiki page that might help.

Last edited by Alexandrite; 02-18-2009 at 06:35 PM..
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  #36  
Old 02-18-2009, 06:33 PM
SkepticDoc SkepticDoc is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Quote:
Originally Posted by AemJeff View Post
If you do happen to recall where you saw that article, please post it here. That's fascinating.
I love GOOGLE! http://www.google.com/search?q=retro...970--2,GGIC:en

The question is if there is any effect on the immune response on future infections from the infection of the retrovirus?

I suspect not, because that would prevent the virus from propagating in the future, making it less "fit" for propagation.

Pathogens are always in a delicate balance, if they are too potent, they will kill the host and limit their spread.

Maybe the "ScienceBlog" contributors can share their opinion...

Evidence of infection in our genome may be just a coincidence in our evolution, or it could be just one more random cause of genetic mutation changing our phenotype. The interaction of the phenotype with other aspects of the environment/ecosystem then would determine the survival of the mutation and eventual transmission of the change.

Would there have been transmission of HIV without random and unrestrained sexual relations?

The "prevention" of Plague and Cholera has to do more with public health and hygiene than with the genomes of the host or pathogen.
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  #37  
Old 02-18-2009, 09:58 PM
AemJeff AemJeff is offline
 
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Default Re: Science Saturday: Darwin the Rock Star

Thanks to both of you.
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  #38  
Old 02-19-2009, 03:36 PM
Tyrrell McAllister Tyrrell McAllister is offline
 
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Default Re: Group Selection

Quote:
Originally Posted by Me&theboys View Post
I am a skeptic about group selection, but would be happy be be persuaded otherwise. I think the concept continues to receive a lot of support in large part because of two factors: 1) it's a shape-shifter whose definition changes in the face of data that does not support it; 2) it makes people feel good about evolution because of its association with behavior that has "pure" altruistic motives.
Here is the paper by E.O. Wilson and D.S. Wilson on group selection:

Rethinking the Theoretical Foundation of Sociobiology

They distinguish the "group selection" that they defend from so-called "naďve group selection". That perhaps opens them up to charges of redefining group selection. However, from what I gather in the article, their definition is a rigorous one. The "group selection" component in evolution is identified with a particular term in certain mathematical equations describing the dynamics of gene-frequencies in populations. At least, that was my understanding of the article. I don't know the mathematics of evolution myself, and the article just refers to famous equations by name, without actually displaying them itself.

The upshot is that well-accepted evolutionary processes, like kin-selection, get labeled as examples of group selection.

Because the paper has no math, I was never certain, but I think that an accurate "gene-centric" description of how group selection could happen is this: (But I may have misunderstood, so please someone correct me if they know better.)

Say you have a species broken up into groups. Within one of these groups, some individuals have a certain gene X. Suppose that X makes its host have a lower reproductive rate than its neighbors within the group. Maybe X encourages its host to sacrifice reproductive opportunities to help other group members get more opportunities of their own. But suppose that X's host helps the group so much that the group as a whole out-reproduces other groups within the species. Then the total size of the group could grow fast enough so that the raw number of X-carriers also grows. That is, even though X makes its host get a smaller slice of the reproductive pie within the group, X is also making the pie larger, so that that smaller slice is still growing as a raw number of individuals, and maybe also as a proportion of the whole species.

It seems reasonable to me to call that "group selection". At the within-group level, X is harming its host's reproductive success. But because of how X affects between-group dynamics, X's share of the whole species grows.

So that establishes the theoretical possibility of group selection, even on a gene-centric account. I gather that it's still a matter of some controversy whether such scenarios really happen enough to be significant. The Wilson&Wilson article tries to marshal evidence that it does, but I'm not qualified to judge whether it adds up to something significant.
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Old 02-20-2009, 05:56 AM
Nate Nate is offline
 
Join Date: Oct 2006
Posts: 195
Default Re: Group Selection

Speaking of Group Selection, I found this @Google talk with Bert Hölldobler and E.O. Wilson on the different selection pressures of groups of insects (primarily ants) fairly interesting.
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