Evolution: Current theory

Great Debates
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My personal bug-bear is poor education in the sciences, which has led me into countless arguments on evolution and the misapplication of ‘the theory of evolution’ to social policy IRL.

So, I am just throwing these links out for general ignorance-fighting. The articles are months old, so many of you may have already read them.

This is the main article with links to 24 other articles, some on misconceptions about evolution, and some on creationism.

This article touches on the issue of intraspecies cooperation, which I brought up in another thread, as does this one..

I think they are fairly easy reading.

I also found this reference to Lynn Margulis, but I don’t know anything about the site.

If any one is up for a different take, try How the Leopard Changed its Spots; I cannot recommend this as light reading, though.

My cousin dont beleive in evolution
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So. How does this support that “Certain traits maladaptive to an individual will persist because they are benefit to the species.” and that it’s better to understand evolution as “a co-operative process within a species.” rather than “a competitive process between individuals”?

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[QUOTE=mr. jp]
So. How does this support that “Certain traits maladaptive to an individual will persist because they are benefit to the species.” and that it’s better to understand evolution as “a co-operative process within a species.” rather than “a competitive process between individuals”?
[/QUOTE]

My computer ate the very long reply I posted as soon as I got home. Probably just as well.

Can I just be casual in my response?

“Survival of the fittest”, in evolutionary theory, was taught to me as something like …

The biggest, strongest, and most aggressive individual will obtain most of the resources, have the most offspring, and spread those genes for biggest-strongest-most-aggressive throughout the population.

However, if too much of the population dies from violence or starvation as a result of the ‘successful’ individual’s actions, the population will not have enough individuals, or genetic variety, to thrive and expand and spread the ‘successful’ individual’s genes.

OTOH, a weak individual with a skill particularly useful to the group, like chipping flints or birthing babies, even one with fewer opportunities to breed will ensure the survival of the group, and the survival of their genes, and skills, through the group. The evolutionary ‘Revenge of the Nerds’.

A successful individual may succeed to the detriment of their breeding pool, and, therefore, the offsprings’ chances of survival. A less ‘successful’ individual may improve their offsprings’ success by ensuring the success of the group.

(I also went on about the true brutality of nature, higher plants, and the issue of inter-species co-operation.)

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The one I see more often is the idea that evolution is an intelligent process.

“Gay people can’t reproduce (by following their gayness), so we cain’t have evolved to have it.”

No, I’m sorry but people who are born sterile also can’t reproduce. We evolved to have them right? Is there any gain to having some small percent of the population be left handed? There doesn’t appear to be and yet we have it. Does it make sense for anyone to have poor eyesight? No, yet evolution has given them to us.

Evolution doesn’t lead to anything. It isn’t smart and it doesn’t know where it’s going or why. Yes, it selects for the most fit, but if it was intelligently travelling down a particular course, there wouldn’t be any other selections but the most fit. To get “the most fit”, it means that evolution has to create a whole bunch of unfits. Point in fact, it has to actively try and create random unfit things so that there’s a variety of creatures to duke it out. If it just cloned the same thing from generation to generation going with what worked instead of trying, possibly stupid, random stuff, it wouldn’t be evolution!

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[QUOTE=Sage Rat]
Is there any gain to having some small percent of the population be left handed?
[/QUOTE]
Well, yes, they are significantly more intelligent, attractive, and witty than their right-handed counter parts.

One of the articles states that evolution does not ensure ‘the most fit’ but only ‘fit enough’. And I think one argues that a species ‘perfectly’ adapted to its environment would be at risk, because it wouldn’t have the genetic variety to adapt to a changing environment. And another that evolution is not always positively adaptive.

Did you read them? Were they informative? I am a poor judge of scientific articles for ‘civilians’.

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How does communication evolve? I mean, if everyone instinctively says, “Ack!” when they see a predator, and everyone instinctively runs when they hear “Ack!,” that’s useful. But what good is the first organism with a mutation that makes them run upon hearing “Ack!,” in the absence of anyone saying it? Or one organism that acks when frightened, if nobody else knows enough to run? Do the acking and the ack-receiving mutations have to arise by chance simultaneously?

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[QUOTE=coffeecat]
How does communication evolve? I mean, if everyone instinctively says, “Ack!” when they see a predator, and everyone instinctively runs when they hear “Ack!,” that’s useful. But what good is the first organism with a mutation that makes them run upon hearing “Ack!,” in the absence of anyone saying it? Or one organism that acks when frightened, if nobody else knows enough to run? Do the acking and the ack-receiving mutations have to arise by chance simultaneously?
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Evolution isn’t about the “first organism” doing anything. If you’re too much of a freak, you die alone, and take your spiffy new traits with you. Rather, evolution is about populations changing. A few individuals might be able to vocalize slightly differently than the rest, and this may somehow enhance their ability to survive and reproduce. If their vocal abilities are heritable, they pass on those genes, and a slightly bigger chunk of the population now has those vocal abilities. And so on. Meanwhile, other, new abilities (read; traits) might be appearing in other members of the population, as well.

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[QUOTE=coffeecat]
How does communication evolve? I mean, if everyone instinctively says, “Ack!” when they see a predator, and everyone instinctively runs when they hear “Ack!,” that’s useful. But what good is the first organism with a mutation that makes them run upon hearing “Ack!,” in the absence of anyone saying it? Or one organism that acks when frightened, if nobody else knows enough to run? Do the acking and the ack-receiving mutations have to arise by chance simultaneously?
[/QUOTE]
Or communication might just arise from the “having more powerful brains” evolutionary thread. Specifically I suppose the ability to empathise and co-ordinate, and remember past behaviours and others.

Anyway, my pet peeve about evolution misunderstood is that it’s a random process.

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j666, yes I understand your point, but I don’t agree with it. I don’t see how detriment to the breeding pool can be relevant for an individual animals’ reproduction, except in species with very few animals left. Actually, even so, I don’t see how it would diminish the offspring of that animal more than it would the offspring of the competitors.

Anyway, as I said, your version of the theory is a non-standard interpretation. Do you have any cites backing it up?

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Yes I DO believe in evolution but the statement survival of the fittest has always struck me as a redundancy.

i.e. Survival of the fittest thing to survive in any particular enviroment put more briefly says survival of the survivors which isn’t incredibly profound IMO.

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It’s confusing because it can be hard to imagine from our perspective why certain “negative” traits persist, when the reasons for selecting for certain traits may be complex, obscure, or maybe even irrelevant to modern life.

To me, the classic “maladaptive yet nonetheless desirable” trait is big brains in humans compared to (female) hip size; before modern medicine a lot of mothers and babies died because the head was too big to squeeze out. My wife had to have c-sections, so I had time to think about it while hiding behind the curtain. (advice to dads: don’t look)

Obviously having a large brain and more intelligence is advantageous enough to offset losing a certain percentage or the population because of it. In whatever fashion, probably many different things, the surviving bigheads had a reproductive advantage. I’m pretty sure its because they could figure out how to work the clitoris so they got a lot more action.

Also people tend to misunderstand/overestimate the evolutionary advantage of individual survival. I.E. it really doesn’t matter if I have a heart attack at 50 if all my reproducing is done by then, it’s irrelevant.

I shouldn’t even address the “gay gene” issue after a few beers, but let’s just say if “10%” of the population has it, despite the (seeming) unlikelihood of it being passed on, logically it must be helpful to the species overall somehow. For examples you might look at sickle cell anemia, or perhaps the way in the animal kingdom, say a wolf pack, not all members have to reproduce themselves in order to help the group to survive. And those might not be relevant, the point is more that we’re taught to consider it from the individual’s perspective rather than the groups. The bee stings and dies trying to protect the colony, and sometimes people do much the same thing.

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[QUOTE=OompaLoompa]
I shouldn’t even address the “gay gene” issue after a few beers, but let’s just say if “10%” of the population has it, despite the (seeming) unlikelihood of it being passed on, logically it must be helpful to the species overall somehow.
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As noted in the “24 misconceptions” link, evolution is not about what’s good for the species.

Furthermore, were there such a thing as a “gay gene”, there are any number of ways in which it could persist in the population, including new mutations (e.g., some 25% of Marfan Syndrome cases are the result of new mutations, rather than inherited genes), the possibility of being a recessive trait, and the fact that gays do reproduce on occasion.

Also, there’s no such thing as a “maladaptive” trait. A trait is either adaptive, or it isn’t. Big brains are adaptive, as is the resultant birthing of babies before they’re “done”.

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[QUOTE=Lust4Life]
Yes I DO believe in evolution but the statement survival of the fittest has always struck me as a redundancy.

i.e. Survival of the fittest thing to survive in any particular enviroment put more briefly says survival of the survivors which isn’t incredibly profound IMO.
[/QUOTE]

It may or may not be a tautology, but it is an oversimplification of how natural selection works. One could very well be “fit” via non-heritable traits, but that won’t make one evolutionarily successful.

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I notice an underlying assumption throughout this and similar threads that Humanity is the most successful species in evolutionary terms on Earth hence the references to co operation,certain famous individuals and skills etc.

But what about Blue Green Algae say?

Or ants?

There are a hell of a lot more of these species numerically then people in the world,covering a great area of the globe and theres quite a good chance that they could outsurvive us come the overdue asteroid strike or similar catastrophic event.

Fair enough they aren’t physically large or have intelligence because in evolutionary terms they dont need it.

You dont put ash trays on a motor bike but their performance isn’t degraded by it.

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If you are interested, I suggest reading Richard Dawkins’s Selfish Gene and Extended Phenotype.

They are hefty reading, but definitely disabused me of any notions involving a species-centric or even organism-centric view of evolution.

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[QUOTE=DrCube]
If you are interested, I suggest reading Richard Dawkins’s Selfish Gene and Extended Phenotype.

They are hefty reading, but definitely disabused me of any notions involving a species-centric or even organism-centric view of evolution.
[/QUOTE]
And Goodwin knocks the idea of “cellular-centric” evolution into a tizzy. All those weird little questions that had rattled around in my brain ('Why bilateral symmetry?"; “Has anyone ever done a serious statistical analysis on the probability of the evolution of complex mammals?”) were rendered insignificant. (I can be quite the bore about that book.)

Lust4Life, I give people the benefit of the doubt, and assume they tend to talk about evolution in terms of their own species because that’s what they know. I also think the complex mammals are pretty amazing.

Darwin’s Finch, and gene - trait relationship is not always one-to-one; a single trait can be influence by several genes, and a single gene can influence several traits. People do tend to think of evolutions as mutation = new trait; and that the new trait gets an immediate pass/fail grade by means of lots of babies/no babies.

oompah, as for you specific example, I wonder if the increased calories, or perhaps calcium, available to pregnant females wouldn’t account for that, if the human (and for that matter cows) evolved primarily as pre-agrarian.

mr. jp, all the cites I found addressed inter-species co-operation, or the “adoption” of other species as organelles by single-celled organisms. I could not find an article on The Competitive Individual vs. The Co-operative Species. I am not the best Searcher; maybe you’ll have better luck. It really isn’t “non-standard” these days. But don’t conflate the entire species with the breeding pool; the individual’s opportunity breed is typically restricted within a certain range.

coffecat, and for communication, well, all species communicate; it is fascinating. I heard on Science Friday (I think) recently that a cicada’s mating call (I think) varies in pitch with the ambient temperature, but that other cicadas respond in the same way to the call, even when it sounds very different.

And inter-species vocal communication? It astonished me how many words and phrases my last dog understood; “sit”, “stay”, and “get off the couch”, ok, but “go look in the living room”? I vaguely remember some research indicating that the mammalian brain is ‘hard-wired’ to seek patterns in any stimulus … but, of course, I can not remember where, when, or by whom.

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[QUOTE=DrCube]
If you are interested, I suggest reading Richard Dawkins’s Selfish Gene and Extended Phenotype.

They are hefty reading, but definitely disabused me of any notions involving a species-centric or even organism-centric view of evolution.
[/QUOTE]

Whereas I have little use for Dawkins’ gene-centric view of evolution. Organism-centirc is the way to go, as far as I’m concerned (and Gould, and Mayr, and Futuyma, and…).

Of course, what one views as the focus of natural selection is largely up to one’s philosophy rather than any absolute scientific truth. So there’s room for all kinds :slight_smile:

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[QUOTE=Darwin’s Finch]
Whereas I have little use for Dawkins’ gene-centric view of evolution. Organism-centirc is the way to go, as far as I’m concerned (and Gould, and Mayr, and Futuyma, and…).
[/quote]
Whereas I believe with the furvour of a neophyte religious acolyte* that all evolution is driven by thermodynamic stability in micro-environments.

*Yes, I realize that means I am probably wrong. Neophyte acolytes, religious or not, typically are.

Of course. Except …

Well, The Mismeasure of Man. Science is influenced by cultural prejudice. One should guard against that. IME, one can distinguish between a reluctance to accept something new (art or science or philosophy) because it offends one’s expectations, or because there is some … internal flaw, even if one lacks the knowledge base to identify it. Think of the original response to the Impressionists, or scientists’ descriptions of sexual behavior of social mammals.

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[QUOTE=j666]

mr. jp, all the cites I found addressed inter-species co-operation, or the “adoption” of other species as organelles by single-celled organisms. I could not find an article on The Competitive Individual vs. The Co-operative Species. I am not the best Searcher; maybe you’ll have better luck. It really isn’t “non-standard” these days. But don’t conflate the entire species with the breeding pool; the individual’s opportunity breed is typically restricted within a certain range.

[/QUOTE]

I still don’t even see how this can happen. Is the point that some animals acquire traits that are so detrimental to the other animals of the same species, that all or most of the females that are near it die out? I suppose this could happen in very specific circumstances, but not as something less than a footnote in the description of evolution.

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Re-phylumed in Great Debates.