Reasons to Believe

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Re: Reasons to Believe

Postby telcontar42 » Mon Oct 27, 2008 4:09 pm UTC

Aikanaro wrote:Question two: The frailties of humans compared with other animals. Let's say we evolved from creatures that were not as smart as us, but had other useful physical traits to compensate for it. Thicker hides, more muscle mass, etc.. Over time we've lost these traits, presumably because they're no longer necessary; our ability to use tools has replaced it. But the thing I don't get is, just because they aren't NEEDED, doesn't mean they aren't USEFUL.

Hypothetical situation: Let's say we have two tribes of proto-humans: both of which are intelligent, can use tools, etc., but one is PHYSICALLY more like apes (muscles, hide, etc.), while the other looks like us. Assuming all other factors being equal, wouldn't the ape-like tribe be more successful? Even if you say the manlike tribe can use things like hides for armor, that doesn't mean the apelike one can't, it's just it would be in ADDITION to its own natural advantages. Having a thicker hide would mean that, say, a hunting accident would be less likely to result in death, or the creatures would be less likely to freeze during winter, etc.. I would think that the apelike ones would become dominant, and would both increase their capicity for tools, AND maintain their physiological advantages. So why has man lost these traits over time?

That's not just a hypothetical situation, it pretty much happened. Early Homo sapiens and Neanderthals were probably contemporaries sharing some territory. They probably had comparable intelligences. Neanderthals were the stronger, more robust species. As a result, they were less efficient. They consumed more energy and had to eat more. Also, they might not have been as fast or as well adapted to warmer environments. Often evolution is less about species improving and more about species adapting to changing environments.

Also, I believe this thread is relevant here: viewtopic.php?f=18&t=24705&st=0&sk=t&sd=a&hilit=hard+to+believe+evolution
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Re: Reasons to Believe

Postby Angua » Mon Oct 27, 2008 4:15 pm UTC

Thing do not evolve in separate bits, but small things over time. I'm not an evolutionary scientist, but this is how I see it could have happened. Birds would have probably developed feathers first (there is evidence of dinosaurs with feathers) and then maybe started out with gliding or short hops like chickens. The would have then evolved the hollow bones, as those ones would be able to fly higher and so get away from danger. They would then be more able to breed and so we end up with hollow boned birds.

For the humans evolving, we are more closely related to chimpanzees. If you look at them, the are not that much more robust than we are, we just ended up coming down from the trees and slowly developed preferences for less hairy mates while developing tools. (I mean, look at how women shave their legs, and tell me that there isn't any preference for being less hairy).
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Re: Reasons to Believe

Postby SecondTalon » Mon Oct 27, 2008 4:20 pm UTC

.... I wouldn't use the fashions of the last hundred years as proof of evolutionary pressures.
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Re: Reasons to Believe

Postby Angua » Mon Oct 27, 2008 4:23 pm UTC

I guess so, but as some people want reasons for everything, I tried to come up with a theory. I did state at the beginning that I was in no way an expert.
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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 4:37 pm UTC

Hygenic fashion, such as shaving legs, can be seen as a part of sexual selection, which is a byproduct of natural selection, and sometimes goes against it. For instance, birds have bright, flashy feathers to attract a mate. Flashy feathers goes against natural selection in that these birds are spotted faster by predators. The red cardinal male does not live as long as the brown cowbird because of being killed more often. However, these colors are meant to show healthiness in the mate; the brighter the colors, the more heathly the male, and possibly the offspring as well. This points us back towards fighting against evolutionary pressures, IE being a healthy bird that fights off deseases and is smart enough to avoid predators.

When a woman shaves her legs, when a man shaves his XXX, they go against natural selection because the hairs act as heat insulation. However it goes towards sexual selection because it reveals how beautiful and healthy the skin is underneath. This points us back towards fighting against evolutionary pressures, IE being a human that instinctively gears themselves towards a healthy bodily organ known as "skin," and not a human that succumbs to the pressure of skin diseases.

Angua, I would use certain fashions of the last hundred years as proof of evolutionary pressures.
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 4:40 pm UTC

Jebobek wrote:Angua, I would use certain fashions of the last hundred years as proof of evolutionary pressures.
If you'd like to use them as hypothetical illustrations, sure. Proof? No.

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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 4:44 pm UTC

Sorry, I should have used it as "a proof." I.E. Angua came across a proof, lets just throw that into the mountain of proofs Darwin came back with.
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 4:49 pm UTC

It'd probably be better to use the coloration of birds to demonstrate that the subset of sexual selection can sometimes oppose higher level natural selection, rather than comparing humans to birds.

Sexual selection criteria regarding fashion in humans changes far more quickly and with a much larger cultural variability than any evolutionary process can explain.

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Re: Reasons to Believe

Postby Angua » Mon Oct 27, 2008 4:54 pm UTC

Azrael wrote:Sexual selection criteria in humans changes far more quickly and culturally variably than any evolutionary process can explain.


Well, humans are memetic (is that a word) as well. As pointed out in the Human evolution thread (can't seem to find it, sorry), our evolution seems to be leading toward memes these days rather than natural selection.
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 4:55 pm UTC

Which, again, would imply that using human fashions to illustrate evolutionary processes is a poor choice.

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Re: Reasons to Believe

Postby Aikanaro » Mon Oct 27, 2008 4:57 pm UTC

I guess question #2 has mostly been answered to my satisfaction, but still not sure I understand with regards to birds, etc..

See, if it were a one-shot, one-variable change, then I could understand. But the problem is that (and again, I'm not a biologist either, feel free to correct me) there are two things needed for flight/gliding: Hollow bones, AND wings. Neither one is really helpful without the other. And it's not the kind of change that's going to instantly happen in one generation either--otherwise, we could easily put it down to the random chaos of evolution popping up, like (bizarre example out of the blue) if a human popped up with eyes that could see a teensy bit further towards infrared than most.

In the case of wings and hollow bones, though, this is an adaption that takes a long time, over many generations. The bloodline in question would suffer for a long time before the payoff kicked in. The "small things over time" argument works for MOST evolutions, such as gradually getting opposable thumbs, or walking upright, etc., but it doesn't seem like it'd work for a gradual shift from something strong, through generations of being a bit weaker, til finally hitting something stronger than you started with. In this particular case, it almost seems like evoltion itself would have to be "intelligent" in order to know about the payoff it was moving towards, like (in a bizarre analogy) when you're playing a video game, leveling up a weak weapon in order to get a more powerful version of it (sorry, I'm a gamer, it's the best analogy I could come up with spur of the moment).

Luck and chance work for explanations, up to a point....but when you have to rely on continuous luck over a long period of time, connected to TWO different, unlikely factors, then it starts to break down.

EDIT: Sorry, forgot to acknowledge the limbs-on-the-back theory....I guess I could see that working, but I'm not sure how much benefit sails that weren't also wings would provide. Not to mention there'd presumably be fossils of some sort connecting this. And now I feel kind of dumb for not thinking of the obvious solution: Any paleontologists-in-training know the "how" of birds evolving from reptiles? Aside from feathers instead of scales, what sort of changes did they go through first: Hollow bones, or wings?

Thanks for the information, folks!
Last edited by Aikanaro on Mon Oct 27, 2008 5:00 pm UTC, edited 1 time in total.
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Re: Reasons to Believe

Postby SlyReaper » Mon Oct 27, 2008 4:58 pm UTC

Azrael wrote:Which, again, would imply that using human fashions to illustrate evolutionary processes is a poor choice.


Or possibly a really good choice.
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 4:59 pm UTC

Aikanaro wrote:In the case of wings and hollow bones, though, this is an adaption that takes a long time, over many generations. The bloodline in question would suffer for a long time before the payoff kicked in.

Raptors had no wings, but had hollow bones. And they didn't *suffer* for it, they were uniquely agile and fast because of it.
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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 5:00 pm UTC

Azrael wrote:It'd probably be better to use the coloration of birds to demonstrate that the subset of sexual selection can sometimes oppose higher level natural selection, rather than comparing humans to birds.

Sexual selection criteria regarding fashion in humans changes far more quickly and with a much larger cultural variability than any evolutionary process can explain.
It may be hard, but is it pointless? To that I say, bologna! Its important to decipher the difference between natural selection and sexual selection in Human history to understand why there are genotypic/phenotypic differences between different nations. By doing so we can begin to predict how the surging increase of sexual selection over natural selection (due to the shifts/merges in cultures) will affect the human race XXXX years down the line.
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Re: Reasons to Believe

Postby SlyReaper » Mon Oct 27, 2008 5:03 pm UTC

Aikanaro wrote:I guess question #2 has mostly been answered to my satisfaction, but still not sure I understand with regards to birds, etc..

See, if it were a one-shot, one-variable change, then I could understand. But the problem is that (and again, I'm not a biologist either, feel free to correct me) there are two things needed for flight/gliding: Hollow bones, AND wings. Neither one is really helpful without the other. And it's not the kind of change that's going to instantly happen in one generation either--otherwise, we could easily put it down to the random chaos of evolution popping up, like (bizarre example out of the blue) if a human popped up with eyes that could see a teensy bit further towards infrared than most.

In the case of wings and hollow bones, though, this is an adaption that takes a long time, over many generations. The bloodline in question would suffer for a long time before the payoff kicked in. The "small things over time" argument works for MOST evolutions, such as gradually getting opposable thumbs, or walking upright, etc., but it doesn't seem like it'd work for a gradual shift from something strong, through generations of being a bit weaker, til finally hitting something stronger than you started with. In this particular case, it almost seems like evoltion itself would have to be "intelligent" in order to know about the payoff it was moving towards, like (in a bizarre analogy) when you're playing a video game, leveling up a weak weapon in order to get a more powerful version of it (sorry, I'm a gamer, it's the best analogy I could come up with spur of the moment).

Luck and chance work for explanations, up to a point....but when you have to rely on continuous luck over a long period of time, connected to TWO different, unlikely factors, then it starts to break down.


I already covered this, but it was on the other page so maybe you didn't read it.

There's nothing to suggest hollow bones can only be useful with wings or vice versa. Hollow bones make the animal lighter and more agile. Wings can allow flight even without hollow bones. And even if they don't, they can increase agility on the ground in the same way that a tail does.

And evolution isn't a continuous chain of luck. Most mutations are bad. It's only the very few that actually provide an actual advantage to the creature in question. The creatures who got a bad mutation were very unlucky indeed because they didn't survive to reproduce.
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Re: Reasons to Believe

Postby Aikanaro » Mon Oct 27, 2008 5:05 pm UTC

Azrael wrote:
Aikanaro wrote:In the case of wings and hollow bones, though, this is an adaption that takes a long time, over many generations. The bloodline in question would suffer for a long time before the payoff kicked in.

Raptors had no wings, but had hollow bones. And they didn't *suffer* for it, they were uniquely agile and fast because of it.


I did not know this! Okies, I think that answers my first question, then....I would have thought that hollow bones without flight were more of a vulnerability than a benefit...

Alrightaru, I'm out ^ ^

EDIT: Sly, I also missed your response, and I apologize. I thought both adaptions were necessary for either to be beneficial. If either alone is useful, it makes a bit more sense.
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Re: Reasons to Believe

Postby Kachi » Mon Oct 27, 2008 5:07 pm UTC

Neither one is really helpful without the other.


I know. All those poor flamingos, penguins, and peacocks.

Also, wtf is up with bats yall?

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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 5:11 pm UTC

Aikanaro wrote:I did not know this! Okies, I think that answers my first question, then....I would have thought that hollow bones without flight were more of a vulnerability than a benefit...
Whats tricky about evolution is that the new mutation may be a higher benefit in one department (speedy+agile) but hurt in another (durability when hit). The reason why the mutation remained there ultimately was because the benefit outweighed the disadvantage. The species survived more and bred.

Take cheetas for example. They have reached to an evolution point where their speed gives them a great chasing ability. However they are prone to break joints which leads them to not hunting and eventually starvation. However, the speed benefit outweighs the risk. The proof is their continued breeding and existance.
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Re: Reasons to Believe

Postby telcontar42 » Mon Oct 27, 2008 5:12 pm UTC

Aikanaro wrote:See, if it were a one-shot, one-variable change, then I could understand. But the problem is that (and again, I'm not a biologist either, feel free to correct me) there are two things needed for flight/gliding: Hollow bones, AND wings. Neither one is really helpful without the other. And it's not the kind of change that's going to instantly happen in one generation either--otherwise, we could easily put it down to the random chaos of evolution popping up, like (bizarre example out of the blue) if a human popped up with eyes that could see a teensy bit further towards infrared than most.

In the case of wings and hollow bones, though, this is an adaption that takes a long time, over many generations. The bloodline in question would suffer for a long time before the payoff kicked in. The "small things over time" argument works for MOST evolutions, such as gradually getting opposable thumbs, or walking upright, etc., but it doesn't seem like it'd work for a gradual shift from something strong, through generations of being a bit weaker, til finally hitting something stronger than you started with. In this particular case, it almost seems like evoltion itself would have to be "intelligent" in order to know about the payoff it was moving towards, like (in a bizarre analogy) when you're playing a video game, leveling up a weak weapon in order to get a more powerful version of it (sorry, I'm a gamer, it's the best analogy I could come up with spur of the moment).

There are several possibilities as to how flight could have evolved. For example, it could have started with animals jumping. The reduced mass from hollow wings would certainly help animals to jump farther, higher, and faster. Aerodynamic limbs would contribute to this as well. It doesn't seem as difficult to imagine the development from animals jumping between branches to gliding down from branches to flying from branches. Wikipedia has brief explanations of legit theories that weren't just made up in my head: http://en.wikipedia.org/wiki/Bird_fligh ... ird_flight.

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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 5:15 pm UTC

Jebobek wrote:Take cheetas for example. They have reached to an evolution point where their speed gives them a great chasing ability. However they are prone to break joints which leads them to not hunting and eventually starvation. However, the speed benefit outweighs the risk. The proof is their continued breeding and existance.


... unless God likes cheetahs and is keeping them around for kicks.

It can be difficult to relate these things to people you have already assumed God's hand in everything. *sigh*

Aikanaro wrote:I did not know this! Okies, I think that answers my first question,

For the record, dinosaurs are awesome. Just ask any 5 year old.

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Re: Reasons to Believe

Postby Aikanaro » Mon Oct 27, 2008 5:18 pm UTC

No, God hates penguins. And he keeps them around just because he likes making them suffer.

(If anyone else here has seen March of the Penguins, that should make perfect sense.)

EDIT: I guess chalk up another one for the Raptors, then?
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Re: Reasons to Believe

Postby Dazmilar » Mon Oct 27, 2008 5:32 pm UTC

It's really not that difficult to imagine a gradual change in bone structure for animals that fly or glide. Look at flying squirrels. Flaps of skin to help you glide from tree to tree. If different squirrels have varying bone densities, the ones with lighter bone structures will glide farther, which increases the range that the squirrels can safely search for food. The heavier squirrels will have a smaller range, less food. More food, more healthy, more squirrel babies, natural selection. This is also a clear example of why it's important to view evolution in terms of how animals become better suited to their environment, not simply, "better." If you just use the word better, it's incredibly subjective. It's better to be stronger and sturdier, right? Except in cases where being stronger and sturdier are not better. After all, a denser bone structure may clearly be sturdier, but it doesn't help the squirrel better adapt to its environment.

As to transitionary fossil evidence. All lifeforms are transitionary. You make a mistake if you think that evolution requires some crazy monster animal hybrids. All of these animals were both suitably adapted for the environments they found themselves in, AND in the process of slowly evolving into new species. But if you're looking for the reptile-bird link, http://en.wikipedia.org/wiki/Archaeopterix

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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 5:33 pm UTC

Yea, I understand that there are many theists that follow a text to a literal meaning, and its frustrating to tell them something apart from the text.

Just to let you know, there are some theists that are fine with the Idea that life came from some sort of electric energy that created early versions of urea, that assembled into early versions of RNA, which self assemble and get surrounded by an early version of a cell membrane.

Some Christians, for instance, believe that God did not directly create these, but have that godly knowledge of where and when humans happen. Then he sent down that Jesus dude to tell them that he 'loves' their existance, and they should love each other's 'existance' as well.

I have a weird personal belief that where if there is a god, or some sorta force of existance, it would not need to put a guiding hand in anything. Chances are that existance of life will just happen to occur somewhere. Yes there can be aliens somewhere, odds are pretty likely, but odds are also likely we won't be able to find them (who knows, though!) I like to tell people that it would be cool if God throws Jesus down on all these planets when the creatures become sentient for a while. People don't like me when I tell them that.

It's better to be stronger and sturdier, right? Except in cases where being stronger and sturdier are not better.
Example: Dinosaurs going extinct and not lil mammals. Although, I would love for it to always be better. I'm talking digimon-giants-with-rockets-firing-out-of-their-nipples better.
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 6:33 pm UTC

Jebobek wrote:
It's better to be stronger and sturdier, right? Except in cases where being stronger and sturdier are not better.

Example: Dinosaurs going extinct and not lil mammals. Although, I would love for it to always be better. I'm talking digimon-giants-with-rockets-firing-out-of-their-nipples better.

And this is why I don't believe in a divine hand in evolution: because those things don't exist and would be totally awesome albeit impossible to explain.
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Re: Reasons to Believe

Postby Aikanaro » Mon Oct 27, 2008 7:00 pm UTC

So if we found a planet inhabited by them, you'd take that as proof of the existence of God? Or would that, like the babelfish, be proof of his nonexistence?
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Re: Reasons to Believe

Postby Random832 » Mon Oct 27, 2008 7:11 pm UTC

qinwamascot wrote:
JoshuaZ wrote:
qinwamascot wrote:I don't know about this. A lot of the bible is historically inaccurate (for example, modern science predicts that the first woman was alive before the first man. But you don't believe in evolution, so this is likely unconvincing to you)


Gah. No. Not what science says. Mitochondrial-Eve was the last common female ancestor of all of humanity. And Y-Adam was the last common male ancestor of all of humanity. Mitochondrial Eve and Y-Adam are not the "first man" or "first woman". Don't criticize people for their science if you don't understand the basics.


Don't assume you know what I'm talking about. Suffice it to say, what I was talking about was not Mitochondrial-Eve. But it doesn't matter either way.


What were you talking about, then?

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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 7:17 pm UTC

Aikanaro wrote:So if we found a planet inhabited by them, you'd take that as proof of the existence of God?
I suppose if you want to ignore humor and try to find meaning in an absurd hypothetical situation then, no. Because *my* version of that hypothetical planet is a farcical offspring of a terminator-esque world where you couldn't prove God's existence back when there were still humans alive to believe in him.

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Re: Reasons to Believe

Postby JoshuaZ » Mon Oct 27, 2008 7:51 pm UTC

Aikanaro wrote:.

Question one: I've heard that Dawkins covers things like eyes existing, etc., in the Blind Watchmaker, comparing it with the Watchmaker argument. Okay, I'm cool with that. I can see Eyes gradually appearing and increasing in usefulness over time. Maybe it starts out you can tell day vs. night, then can pick up shadows of motion, etc., etc.. The problem I have is when you have an evolved trait that's actually a HINDRANCE until it reaches a certain point.



This is one of the better objections to evolution out there. Frankly, I'm surprised that it isnt used by anti-evolution advocates out there. The truth is we aren't really aware of systems like this.


Take birds and their wings (not to mention hollow bones) for an example. How does that start out? Maybe extra flaps of skin, which just get in the way?

Doesn't get in the way. Can have at least two purposes 1) heat regulation 2) gliding or increasing jump length. Note that so called flying squirrels do exactly this and different forms of flying squirrels have different degrees of such skin, all the way from flaps that are small enough that you wouldn't notice them at first glance to huge scary things attached to their arms.

A skeletal structure more susceptable to breaking, and one that doesn't knit as well, due to hollow tubes for bones? I would think that any creature that started down this evolutionary path, would actually reproduce LESS until if and when it finally hit that point where it was capable of gliding and/or flight.


Hollow bones aren't as bad as you make out. Even if you are on the ground hollow bones can be useful if you need to be fast. They also take less calcium to produce. Hollow bones are a problem if you were in species like say a human or a wolf which needed to survive many violent encounters but it isn't as much of an issue otherwise. Hollow bones can be quite strong. And there's some reason to believe that the bones of birds got more hollow as birds became more flight oriented. Archaeopteryx for example has hollow bones but the evidence (as I understand it. I haven't studied bird evolution in detail) suggests that they are less hollow than that of the modern bird.

How does evolution account for these "one step back for two steps forward" changes? Shouldn't each change generally result in immediate benefit, or else the creature would be passed up by its more (immediately) better-adapted cousins?


Yes. See above.

Question two: The frailties of humans compared with other animals. Let's say we evolved from creatures that were not as smart as us, but had other useful physical traits to compensate for it. Thicker hides, more muscle mass, etc.. Over time we've lost these traits, presumably because they're no longer necessary; our ability to use tools has replaced it. But the thing I don't get is, just because they aren't NEEDED, doesn't mean they aren't USEFUL.



Well, usefulness doesn't mean you have high selection pressure. Also having thicker hides, more muscle mass etc. means that you have fewer resources going to the brain and other things that humans have that are well-developed. The niche for humans is that a) we are really smart and b) we are really flexible. We aren't the fastest species, we're not the strongest, we're not the best swimmer but we're pretty fast runners, pretty strong, and pretty good swimmers. Humans are sort of the jack-of-all-beneficial-traits and then we get brain power on as gravy.

Hypothetical situation: Let's say we have two tribes of proto-humans: both of which are intelligent, can use tools, etc., but one is PHYSICALLY more like apes (muscles, hide, etc.), while the other looks like us. Assuming all other factors being equal, wouldn't the ape-like tribe be more successful?


Not necessarily. If you are more ape like that means you need to consume more protein and you aren't going to be as smart. You are correct that if you had humans who were just like normal humans but stronger that they would likely outcompete the standard human. But that sort of thing rarely occurs in nature. There's some evidence that something like this happened with Neanderthals. They may have been slightly less bright or even at the same intelligence level but caloric consumption and other issues made them lose even though they were physically stronger than modern humans. Remember, food resources for most of human history were scarce.

Edit:Formatting
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Re: Reasons to Believe

Postby Azrael » Mon Oct 27, 2008 7:54 pm UTC

You did *not* need to quote that wall o' already quoted text for that short of a response. Please, stick to the relevant-to-your-response part and cut out the chaff.

EDIT: Thank you. :D
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Re: Reasons to Believe

Postby JoshuaZ » Mon Oct 27, 2008 7:59 pm UTC

Azrael wrote:You did *not* need to quote that wall o' already quoted text for that short of a response. Please, stick to the relevant-to-your-response part and cut out the chaff.


Er I did. The formatting got screwed up so it looked like I was quoting more than I was. I've fixed the formatting. Clearly I need to use the preview button more.

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Re: Reasons to Believe

Postby Angua » Mon Oct 27, 2008 8:02 pm UTC

@ Azrael: I think he just messed up with the quote tags.

@ JOshuaZ Preview your work though before posting.

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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 8:18 pm UTC

The problem I have is when you have an evolved trait that's actually a HINDRANCE until it reaches a certain point.
By the way, could you please give me an exaple of this? Im sorry if you already used one and I missed it. I kinda want to help clear some things on the evolution theory.

Novel mutations that gives something a %100 hindrance trait do not lead to better reproductive success. This means the species will not evolve this trait.

The "evolved trait thats actually a HINDERANCE" must have some sort of benefit as well that outweighs the hinderance. If we did not see the benefit we are simply not looking hard enough!

Hope this helps
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Re: Reasons to Believe

Postby Kaiyas » Mon Oct 27, 2008 8:43 pm UTC

Some mutations simply have a null effect, too. (I'm pretty sure about this one)

Neither better nor worse, yet they may have more useful combinations with other flipped genes. (May or may not be correct. I think I heard something from Richard Lenski's Long-term Evolution Project about this)
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Re: Reasons to Believe

Postby Aikanaro » Mon Oct 27, 2008 9:26 pm UTC

Jebobek wrote:
The problem I have is when you have an evolved trait that's actually a HINDRANCE until it reaches a certain point.
By the way, could you please give me an exaple of this? Im sorry if you already used one and I missed it. I kinda want to help clear some things on the evolution theory.

Novel mutations that gives something a %100 hindrance trait do not lead to better reproductive success. This means the species will not evolve this trait.

The "evolved trait thats actually a HINDERANCE" must have some sort of benefit as well that outweighs the hinderance. If we did not see the benefit we are simply not looking hard enough!

Hope this helps


The example I cited (and was already corrected about) was hollow bones. I thought they were too much of a liability to any creature that didn't also possess wings, but didn't realize they provided so large a benefit to a creature's agility.....
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Re: Reasons to Believe

Postby SlyReaper » Mon Oct 27, 2008 9:45 pm UTC

Kaiyas wrote:Some mutations simply have a null effect, too. (I'm pretty sure about this one)

Neither better nor worse, yet they may have more useful combinations with other flipped genes. (May or may not be correct. I think I heard something from Richard Lenski's Long-term Evolution Project about this)


This. A mutation doesn't have to make a creature more successful at reproducing in order for that trait to stick, simply successful enough to reproduce. Humans will tend to sprog 2 or 3 times in their life on average, whereas a bacterium will split roughly 50 times before dying (Hayflick limit or something). This makes bacteria considerably more successful at reproducing than humans. And yet, here we are. :mrgreen:
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Re: Reasons to Believe

Postby Jebobek » Mon Oct 27, 2008 9:55 pm UTC

Aikanaro wrote:The example I cited (and was already corrected about) was hollow bones. I thought they were too much of a liability to any creature that didn't also possess wings, but didn't realize they provided so large a benefit to a creature's agility.....
Sorry about being redundant :(
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Re: Reasons to Believe

Postby Kachi » Mon Oct 27, 2008 10:38 pm UTC

You also have to keep in mind that selection as a concept does not always come down to animals fucking and not getting eaten.

A relatively strong group can be wiped out by things that had nothing to do with what is typically thought of as natural selection. For example, we drive species into distinction. While strictly speaking, that's natural selection too, it doesn't always mean that stronger species will survive. We might kill a species because it's too strong, but ignore others that pose no threat. So that strength becomes a weakness for selection.

Or an asteroid could come crashing down and wipe out entire species (sound familiar?). I think someone may have already pointed out that "strength" is really more accurately "adaptability to the specific situation." Think of obesity (though ties to genetics are still pretty questionable). For most people, obesity is a detriment, but every once in a while, I guy gets stabbed or skewered and the layer of fat saves his life.

Sometimes it's just plain dumb luck, but that's a part of selection too.

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Re: Reasons to Believe

Postby Mane » Mon Oct 27, 2008 11:11 pm UTC

Kachi wrote:You also have to keep in mind that selection as a concept does not always come down to animals fucking and not getting eaten.

A relatively strong group can be wiped out by things that had nothing to do with what is typically thought of as natural selection. For example, we drive species into distinction. While strictly speaking, that's natural selection too, it doesn't always mean that stronger species will survive. We might kill a species because it's too strong, but ignore others that pose no threat. So that strength becomes a weakness for selection.

that's not natural section, that's Artificial section.

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Re: Reasons to Believe

Postby JoshuaZ » Mon Oct 27, 2008 11:18 pm UTC

Mane wrote:that's not natural section, that's Artificial section.


The line between artificial and natural selection isn't so great. Humans are part of the natural world. The only real distinction is that humans intend to actually make the selection. But even that isn't always true. For example, sometimes we are nice to the animals that help us and not nice to the others. In an area that has many stray dogs you'll find that the stray are often very friendly to people. That's because the friendly ones get food from humans and the really unfriendly ones get killed. Now, is that artificial or natural selection? If you say it is natural selection then what if I know about this effect when I feed food to stray dogs? Biology and science in general can do very little based on intention. Overall, artificial selection is best thought of as a specific subset of natural selection.

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Re: Reasons to Believe

Postby Kachi » Tue Oct 28, 2008 12:48 am UTC

Aye, all things are natural, even humans. We are not simply observers of natural selection. We play an active role in it. When we select animals, its not categorically different than any other animal having selection roles for another.


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