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The Theory of Evolution: Evolving!
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Yes, it is. And nowhere did I say there was a lack of selective pressure. In fact, were you to read my post instead of knee-jerk "nu-uh"-ing it, you'd see that I said quite the opposite - that would be the whole "there is still selective pressure, it's just on a different scale than we're used to talking about when it comes to evolution" part of my post. The part that is "made of wrong" according to your ironically incorrect statement. Read first, COMPREHEND, then comment, please.
Incorrect. Not only is that the complete opposite of the truth, the whole paragraph is damn-near self-evidently and obviously correct. You have not (an cannot) find anything there that is not correct. If anything I said there was wrong, it would put a lie to what you said about selective pressure, and you can't have it both ways. I shudder to think of the kind of "education" that would lead you to make such an obviously contradictory error and be pleased with yourself for doing so.
Stop denying things that I never said. All you're doing is telling me I'm wrong, and then proceeding to talk about things that I wasn't wrong about. Perhaps by "wrong" you mean "correct" and it's a simple problem with English vocabulary usage, which would make sense considering how bad a reader someone would have to be in order to get what you seem to have gotten out of my post.
Like the immense mistake that is your entire post? Sheesh. I even re-read my post to see if anyone intelligent could read it and say "you're wrong." I found nothing. Focus on reading comprehension before replying next time, please. It will stop you from saying embarrassingly dumb things like this.
Now, grendel824_
Regarding a lack of selective pressure, I would point out two things. First of all, just because you didn't say that there is no selective pressure, does not mean that there is not selective pressure. Second of all, it would be rather streching the definition of selective pressure to declare that it was still anything but a minor footnote in the First World (which in context your original post applied to). So, you admit that only a small minority of people die before reproducing - and of those, an even smaller percentage die due to defect, disease or limited resources. You're saying natural selection doesn't work that way anymore, well then, how exactly do you propose it does work? Bear in mind that natural selection can only work when significantly different numbers of individuals for different alleles successfully reproduce compared to the overall number of individuals who reproduice within a population.
Regarding the sentence which makes no sense, I was mistaken there, on a second reading I can understand what you're saying and it's pretty much accurate.
Regarding the paragraph of wrongness it ends with "Debilitating/fatal conditions no longer have to stop procreation or kill those people as quickly, and as such we get guys like Stephen Hawking living longer and contributing to our survival by improving our knowledge base. It looks like natural selection is working wonderfully."
Note that it includes the factually incorrect statement of "natural selection is working wonderfully", which as I pointed out cannot be the case (unless you know something I don't). However, juxtaposed with the discussion of Stephen Hawking and his contributions to society, as well as the fact that guys like him no longer die it becomes even more confusing. If guys like him no longer die, then it would seem self evident that things are not being selected against. The fact that he is contributing to society and our survival has nothing to do with natural selection. However, the fact you link it to natural selection as the conclusion of your paragraph requires explanation - it seemed more reasonable to assume that you could actually form a coherent thesis (but were a victim of the common confusion between the metaphorical and literal meanings of the term) rather than simply randomly producing sentences.
If we're giving advice though - if you're going to be so abrasive, it helps to be correct.
The spanish flu killed whole families, but left their neighbours untouched. Suddenly out of nowhere, some otherwise pretty useless genetic information was life or death. It swept over europe in one go, but after it was gone the presence of that gene was certainly more prevalent.
And when we went to the new world, we introduced al these diseases, that were minor nuisances in europe mostly, to people that have not been in contact with them. It was a massacre of untold proportions.
All these 3 examples show very well that if you leave a population without pressure on a specific thing for a time, the consequence is dilution of the genes that provide protection.
But I agree, the evolution of the human race, at this time in the first world, is mostly reliant on evolving our understanding of ourselves and the world around us. This started when we began actively changing the world to fit us, instead of fitting in.
A perfect example could be the narrowing of female hips. Historically, women who had a narrow pelvis usually had increased difficulty birthing a child, and childbirth would sometimes result in the death of the mother and child. Since the advent of C-section style births, this trait has practically been nullified, so a gene that would not normally be passed on, i.e. narrow hips that are not conducive to childbirth, continues to be passed on through each subsequent generation resulting in an overall increase in the appearance of a trait not conducive to the survival of the species. Of course, one could also theorize that natural selection is acting upon the population, as those women with narrow hips are more actively selected as breeding partners, so the population is increasing by that method.
I'm sure there are other examples, but I think the research into our own natural selection as it has changed in response to our technology would be fascinating.
Which is not to say that they're being selected for, by any means.
The fact that any narrowing of the hips would largely rely upon genetic drift as the mechanism pretty much disqualifies the notion that female hips are narrowing because genetic drift is ridiculously slow in large populations and can easily be swamped by simple random variation.
EDIT: It's like the idea that blondes are dying out because everyone can be blonde now. Which is fairly clearly not a reason for blondes dying out. Blondes are of course in no way prevented from breeding, and it seems unlikely that in the past there was significant selective prpessure against non-blondes keeping blondes afloat. It's weird Larmarckian ideas running afoot in the popular consciousness.
Link it back to the point made earlier about child rearing - social constructs that protect weak but otherwise useful individuals are a powerful adaption. Human societies that, say, preserve and learn from elders or veterans have a jump on those that do not for the price of a few meals.
As learning, rather than programmed beings, the drive to protect potential and/or proven knowledge centers is an evolutionarily useful offshoot of our social structure. Just as a wolf's pack mentality is useful evolved behavior, so is our limited exception to selection (note the "limited" - Stephan Hawking does not have a large family, he's still reproductively challenged...things don't have to die as children to be selected against, they can be selected against simply by being relatively less successful adults).
I think there needs to be a conceptual line drawn between the first world's ability to adapt to die-off pressure and the idea that there is NO selection pressure in a modern society.
I think what we're doing is, in effect, giving genetic iterations more time to succeed or fail. We're leaving them in play longer, effectively lengthening the generation.
I host a podcast about movies.
Yes, this exactly. In fact, there's some evidence that some males who may have been cuckolded (that is, their mate may have mothered offspring from a different father) invest more in their sister's offspring! They are guaranteed that their sister's offspring has around 25% of their genes, while there's a chance that their mate's has none. This is also why we often see infanticide in some species (performed by the mother). If the current offspring has little chance of surviving, the mother benefits more from getting rid of that child and starting over with a new one.
This situation is seen in human populations in that humans are K-selected (we have few offspring so that we can invest time and energy in that one or two or so offspring to give them a good chance of survival. Compare to R-selected, like fish, who have lots of offspring because, damn, SOME of them have to survive!). Of course we don't usually try to have as many children as possible! Theoretically, a woman could bear something like 30 children (age 14-35, given ten months [takes a little while for fertility to return after birth), but if she and her mate (if he's around) are only bringing home enough resources (money) to care for five children, even fewer offspring will survive.
And, of course, we all think about reproduction in different ways.
I host a podcast about movies.
Thios goes waaaay back. I recall they found some fossils of early humans that had lost all their teeth. The best explanation is they kept old people around and ever chewed their food for them well past the time they'd be physically able to get food.
And human reproduce slowly in many instances because we have very long development time and need to learn lots of skills from our parents to properly survive. If you've got 30 kids running around that's really difficult.
"Mostly what [the author of that quote/essay] wanted to show is that natural selection is NOT the primary factor in human evolution, because we can freely continue practices such as abortion and taking contraceptives which natural selection would have weeded out in other species."
"No one is arguing that humans don't have a reproductive drive, though you do seem to be forgetting that humans both today and in the past choose/have chosen not to reproduce, which shows that statement 7 is false. The point is that some people, Darwinians in particular, claim that natural selection is true of ALL species at ALL times, which is an obvious falsity. The fact that humans have a reproductive urge is not proof that we'll act upon it. Who would seriously believe that?"
"Finally, if a theory that purports to explain everything only explains 99 out of 100 cases it is false. "
"Both [graduated and punctuated equilibrium] theories are consistent with fairy tales: they tell us that a frog can turn into a prince, the only difference is how long the metamorphosis takes."
Man I don't even know how to respond. He did ask me also if I had any suggestions for reading about evolution. Do you guys know some good straightforward books that aren't totally "GOD SUCKS" like Dawkins but still might be helpful in showing a misguided person why evolution is the best explanation?
Actually, the Selfish Gene is a very good book on Evolution. Yes, it's written by Dawkins, but it doesn't actually address the whole God thing, it's strictly about Evolution.
Edit:Godsdamnit, Andorien!
Anything out there that's similar? I need to come up with something so I can send it to him then relax and go play Brawl, this is bothering me.
EDIT: Blah this is dumb. He already thinks I'm a stupid wanker so I suppose I'll just give him a short reply and leave it at that.
No joke, and it wasn't a worldwide-spread technology until like two generations ago. Also, in the past (and in several regions of the world right now, like Afghanistan), the odds of dying in childbirth were so high due to the sheer number of ways you could die that hip width probably wasn't that big a factor. A woman in Afghanistan has a one in eight chance of dying in childbirth right now. One in eight. Its roughly 1 in 20000 in a developed country. Infection, haemorrhage, shock, blood pressure problems and other things are probably a lot more important than pelvic morphology.
Besides, a wide interior pelvic shape and a butt like kim kardashian aren't actually that correlated. Not to mention a 6' tall women with 38 inch hips and a 5' tall women with 38 inch hips look totally different. It's the different fundamental structure of the female hip and the production of relaxin during pregnancy that make birthing possible.
I host a podcast about movies.
That would explain the dickishness. No worries.
The same reasoning applies to the fact that I didn't advocate eating rocks as a healthy diet either. You're still off your rocker if you start acting like you're proving me wrong by shouting "rocks will break your teeth!" :rolleyes:
That would depend greatly on the semantics of whatever definition we might care to agree upon. It can go in many ways. Where it CAN'T go is my post being "full of wrong" because I bothered to point out that selective pressure (which at least now you're admitting that I never said didn't exist - small favors!) may still be in effect but at a scale and with a mechanism that is very different from what we're used to applying the term to. Which again, was what my entire post was about.
I propose that it is still at work on the population, and we'll see really obvious evidence of it the next time an extinction-event level rock comes flying at us - either we will have developed the awareness and means to stop it from killing us or we won't quite make it and join the dinosaurs. That's a textbook example of "natural selection" while at the same time being a textbook example of that mechanism operating on a different scale than it is usually referred to. You'd have to be particularly dense to not get the right idea from that, I'd imagine. I'm curious to see if you cock up this post as badly as you (or whomever) did my last one...
That's a more narrow and therefore "incorrect" version of what I'm referring to. We can agree on that needlessly specific definition and it would change my answer at least to the point where it's both harder to explain AND chock full of many more unknowns, but that's not what I'm interested in.
No worries. There's been a rash of people saying spiteful things about pieces of quoted text from me that have nothing to do with anything I've actually said lately, so excuse my frustration.
I guess I do (or, as I posited, I was using a much more general definition of natural selection than the one you're attempting to shoehorn onto my argument). Take your pick.
No, and that shows what you seem to be missing. It's only self evident that there are CERTAIN THINGS that are no longer being selected against. He is still encountering pressures from the world at large and is also contributing in his way to our species. People who are too stupid to look both ways before crossing the street encounter "natural selection" when they're run over. The fact that it's "man-made vehicles" that are doing the running-over doesn't magically make it "not natural selection." That's just anthropocentric nonsense.
Untrue - it's already been more than proven by people better at this than I that natural selection is also relevant to the survival/development of a species as a whole. Otherwise, you again needlessly abandon the term once things like "self-sacrifice" start entering the picture, and again scientists have already proven that natural selection still has a hand in seemingly "selfless" behavior.
Well, I've got that down - I'm pretty self-evidently correct, unless you start redefining your terms much more AND less strictly where absolutely convenient to making you not look so churlish by pooh-poohing my entire post with inaccurate criticisms. As fun as that may be for you, it's not the least bit productive.
Modern human beings are a significant exception to the rule for one major reason; we have technology. More importantly, though; we have technology that has developed ridiculously faster than natural selection can affect any one population of organisms. Humans in modern and first world societies very often to do not partake in actions that are advantageous to the proliferation of their own genes, but this is because humans in modern societies are like fish out of water as far as natural selection goes. We evolved for thousands of years in hunter-gatherer societies on the plains of Africa, if you displace us to an environment so enormously different then of course our inherited behaviors will not translate well. It's completely and totally ridiculous to say that something like abortion or contraceptives factored into our evolutionary past, these things didn't exist 100 years ago, much less 100,000. Through technology people have managed to increase the survivability of society incredibly, but at the same time this technology is not at all based around the survival of our genes, and has been detrimental to it in many respects (while coincidentally beneficial in many others). While your sister's boyfriend makes the point that while humans have an urge to have sex and reproduce, we often do not act on it, he does not take into account the fact that this is a relatively new development (like, 4 or 5 thousand years old). In hunter-gather societies, when someone had an urge to reproduce they generally did act on it (though we could have a much more in-depth discussion about why they might not, and why abstaining in many instances would be beneficial to their genes), and in general sex did lead to offspring, and many behaviors that humans have that are not at all adaptive in the current situation were actually incredibly adaptive.
Also, the "99 out of 100" reasoning is bullshit, because it's more like "999,999 out of 1,000,000". Furthermore, natural selection does not purport to explain everything, it's supposed to explain most things. There are other huge factors in evolution and the change of species over time, like genetic drift and migration. The only pressure at work in evolution is not natural selection. However, it is by far the most significant one.
The person does not understand what natural selection means. Natural selection is tautologically true. The question is not whether natural selection still affects human beings, the question is what are the selective pressures that affect human beings.
I've brought up birds of paradise before. Some have almost no natural predators and unlmited food so, like human beings, they aren't being selected against by factors like "starving to death" or "getting eaten by beasts." However, they are selected against by factors like sexual selection which, not coincidentally, is the driving force of their evolution.
Theories like biological evolution and relativity are limited to a certain applicable realm. For example, relativity cannot explain shit at a quantum level. Biological evolution only deals with genetic replication; it cannot explain how early chemicals developed over time into RNA and DNA and protocells, nor can it explain cultural evolution in human beings.
But in its applicable realm, I have yet to see any example where biological evolution does not adequately explain something.
The "frog into prince" statement makes me wonder if this person has even a rudimentary understanding of how evolution works.
An 8th grade biology textbook ought to do it. Or even the Wikipedia entry on evolution. It sounds like he doesn't actually understand what evolution is.
As for how the individual possessing the genes knows who is related to them, we obviously don't take DNA tests for everyone around us so it's probably something we pick up from proximity to them and how others around you treat them. This makes sense, as people often do treat people who are not related to them like relatives, almost being "fooled" or "fooling themselves" into acting like a relative, for instance there are plenty of adoptive and step parents who treat the children they're in care of just like their own children (though I might add that if that bond doesn't develop it leads to incredible problems, evidenced by the fact that step parents pretty much have monopolies on child abuse, closely followed by actual male relatives who did not have a significant hand in raising the children who might not have developed that bond). This behavior isn't adaptive, but it's a relatively new development. Adoption of unrelated children doesn't occur in tribal societies (as contrasted to adoption of related children), and in some tribal societies they even went so far as to treat "remarriage" the way lions do (the children from the previous marriage were actually killed).
Anyway, discuss?
Also, I would argue that groups obviously are selected for, in the tautological "they either survive to spread or don't" sense of natural selection. But the extent to which this kind of selection trickles down into the nitty-gritty engine of evolution (mutation and selection on the gene level) is debatable and probably varies from one case to another.
Well, I agree. What I'm sort of arguing is that no individual gene is going to be attributed to group selection. The only case where that could actually occur, as I said, I think, earlier in the thread, is if the group can not survive unless the vast majority of the members of the group have to have that gene. In order for that to even occur, though, the group would have be so fragile that it probably wouldn't have ever developed in the first place.
What do you personally think about it?
What do I think about group selection? I still need to read The Selfish Gene; I know Dawkins and others kind of destroyed its perceived legitimitacy a few decades ago. But then I read something in either Science or Nature not too long ago about how it's making a comeback.
As a layman, I don't see why group selection is mutually exclusive with the selfish gene model. Intuitively, it makes a lot of sense to me. Especially since it verges on kin selection, which is based on the selfish gene model. I imagine that the degree to which group selection actually factors in evolution is proportional to the degree to which a "group" is internally homogenous and exclusive (i.e. resembles an organism)—with colonial organisms and beehives on the one end of this spectrum and far-flung herds on the other end.
To be honest, I'm sort of a "Dawkins and friends" fan-boy, so that's where pretty much all my conclusions come from.
Anyway, I think the important distinction to be made is between kin selection (now that you mentioned it, I remember that term) and group selection. There should be a definite cutoff point at which another organism is not likely enough to share the same genes as you that it can no longer be safely assumed that it does. Even in a very homogeneous population there's only a certain point to which you can assume that the others in the population share your gene. Past that point, an organism could get away with having a gene that made it appear like they were sharing your gene and because of the disadvantage that a gene that focused primarily on benefiting the population would give to the organism's ability to reproduce, the gene would be pretty quickly replaced by the gene that takes advantage of it.
As far as how non-kinship related altruism might develop, I think it has to work somewhat like the programs that win the iterated prisoner game. Where they try to judge whether the other individual will try to screw them over or not, and if the individual ever does then they stop trying to help and start screwing the other individuals over.
Again—layman here, but as I understand it groups can develop strategies for dealing with cheaters (obviously the "group" isn't actively developing these strategies—the genes in the groups are, but you get the idea). One example are cells in a multicellular organism. Most cells in your body are genetically programmed to die. They have other restraints that physically prevent them from "cheating"—from absorbing more than their share of food, from multiplying out of control, etc. Cancer is something that happens when these restraints fail.
Groups of organisms may also have mechanisms that control cheaters. In beehives, the queen is the only bee that is physically capable of reproducing. The other bees are genetically programmed to work for the queen's benefit. Groups of animals (especially humans) have social behaviors that punish cheating.
So, while I think you're right to point out how cheating can quickly evolve in groups, I also think that—depending on how much selective pressure is exerted at the group level—counter-cheating behaviors and physiology would also be selected for.
This explanation would depend on the organism's ability to detect and understand reciprocity. But it could work for a number of animals. Apart from that, kin selection does a pretty good job of explaining altruism in many species.
Dear lord, I'm ashamed of my inefficient writing lately. Thanks for saying what it took way more text for me to say and doing it far more effectively. I'm going to have to start running my posts by you for you to interpret and make them sound smarter and more succinct.
Or, if you prefer fiction, The Time Machine (Wells was a student of Huxley, and the possibility that humanity is not a final result was a fairly consistent theme in his science romance).
It seems mind-boggling to me that they bring up something like transitional fossils as somehow being a stumbling block for evolution, yet even if there were ZERO transitional fossils that were vaporised by whatever, there's still the undeniable proof in life's genetic code. They say "Well even Darwin said if we couldn't find the fossils then we should abandon the idea of Evolution!" Well, Darwin didn't know about modern fucking genetics and DNA.
Hell, even without that the strongest and must undeniable proof for evolution is the fact that it doesn't claim what people like Ben Stein seem to think it does. It doesn't address how life first arose, and doesn't need to. It doesn't address whether or not an intelligent designer could be responsible for the world as we know it, and doesn't need to. It's really, really simple:
There's a bunch of evidence that organisms have changed significantly over time. Here's what could explain how that happened without making leaps of logic to assume supernatural or completely mysterious events. If incontravertable proof of an intelligent designer (God or aliens or whatever) was found, it wouldn't do ANYTHING to disprove or discredit the basic tenets of the theory of evolution any more than the idea that some Jesus guy turned one loaf of bread into a whole bunch disproves or discredits number theory and implies that there's something wrong with teaching kids that 1+1=2.
It's telling that it is so completely solid a theory that it doesn't need to discredit more fanciful ideas to stay valid, but ID proponents seem to have so little faith that they feel that they MUST somehow prove evolution wrong. I actually wonder why there was no Scopes trial over teaching basic addition using the aforementioned Bible story...