You're certainly right that the old concepts of some sort of linear progression culminating in mankind are inaccurate. But that doesn't mean you have to deny any sort of progression, or any sort of objective criteria for discerning superiority or fitness between species.
Good point. However, this is more or less what I was getting at with the phrase "survival of the fittest for a certain environment" bit.
The objective criteria you mention must take the organism's habitat into account. You know this, I know this, but the problem is that many other people don't know this. The phrase "survival of the fittest" without the qualifier is what most people understand evolution to be, as if there were some measure of fittness that wasn't relative and subjective. This in turn leads to all sorts of misunderstandings about how evolution works, the most disturbing of which can be seen in 19th century social darwinism.
Plus, it's worth noting that not all evolutionary progress pays off. To get back to your own counterpoint about amphibious fish surviving when the pond dries up, those same fish would be a less successful species right up until the point where the water based life dies. They'd probably be a marginal species that outlives the specialists by a stroke of luck.
This is where genetic diversity matters - you never know what sort of arraingment is going to work best in the future. Often the generalists outlive the specialists, and humans are definately in the specialist category (we're completely dependant on man-made tools to survive).
As for us humans, I would argue that our environment is a technological one, and that we only consider ourselves highly evolved because we're basing our criteria on ourselves. In other words, our survival strategy is toolmaking, so we're biased in favour of that strategy over any other. I don't think it's possible to look at what we've evolved for objectively, anymore than an individual can judge themselves impartially. And it's way to easy to get into circular reasoning.
Short version: We now know that patches of photoreceptive cells can develop without the surrounding structure of the eye. Furthermore, having minimal sight is substantially better than no sight whatsoever, so even "half an eye" is workable from an evolutionary perspective.
So incremental development is possible, beginning with a retinal precursor, and slowly developing layers of complexity that give rise to the various types of eye (for example, human eyes and compound eyes, which are dissimilar in configuration, but serve the same function).
Yeah, but that doesn't excuse changing the meaning of the original quote. This is like taking "John went to the store" and altering it to say "John went to the [book] store", when John actually went to the video store. My point that organ =! organism stands.
True, but the ability to adapt to alien (and I use the term very generally here) environments is not what our survival strategy entails.
Our survival is essentially rooted in toolmaking and inventiveness. There are other examples of species that employ tools, but none to the same degree that we do. Virtually everything that we need to survive, and everything that sets us apart, is rooted in this adaptation.
This is not the survival strategy of a generalist, it's the way of a specialist. We've got all our eggs in one basket. That basket has paid off in many unique and useful ways, which allow us to do things like survive in environments that are radically different from the ones we initially evolved in, but fundamentally we're still specialized.
The environment we're fit for is a technological one, rather than a geographic one.
Does this make us unique? Yep, but that's hardly an unusual affair for specialized animals. Does that make us intelligent? Hell yeah, but then we only consider intelligence/sapience so important because it's the only shtick we've got. There's a quote that goes something like "I used to think the mind was the most interesting part of a person - then I thought 'hey, wait, look who's telling me that'", which sums up our emphasis on brains quite nicely.
You do realize that the quote didn't say "organism", right? It specified "organ", which is a major difference in biology. Organs have pretty much zero to do with gene count, and in any case single celled organisms don't really have organs in the normal sense of the word.
What Darwin was saying was essentially that if an organ were encountered that could not have developed incrementally, then that would disprove his theory. People have tried to show that the eye meets this criteria, but we now know that light sensing organs can develop incrementally. Wings have also been brought up as a potential arguement, but are counteracted by examples of wing-like structures that serve some intermediate purpose other than flight.
Plus, gene count does increase incrementally, so even if Darwin had used the word organism, your answer would still be "no". Gene count is really pretty irrelevant as a measure of complexity, and in any case is easy to increase slowly over time with mutation.
Well, the main problem is the public perception that evolution produces "superior" species. This is rooted in a 19th century mentality that held to a notion that there were "upper" and "lower" life forms (which incidentally is a view that predates natural selection by a good many years, and is arguably not confined to the 19th century). When you talk about the views held by the average non-scientist regarding evolution, the most common perception is "survival of the fittest", with the implication that those that survive are somehow better objectively.
In actuallity, survival of the fittest implies fittness for a certain environment only. To borrow someone else's analogy, you can have the best gills in the pond and you'll still die off with the rest if the pond dries up.
The problem is really the human ego; we have an enourmously hard time accepting the idea that humans aren't innately special. We're intelligent, certainly, and we're unique, but then again every species that has a highly specialized survival strategy is unique.
Where did I say scientists are infallable? I didn't, and I dislike the accusation.
My point was more that a scientist with years of schooling and anywhere from years to decades of practical experience (and the wherewithal and curiosity to keep at it) is likely to know what he or she is talking about in their field. I allow for the possibility they are wrong, hence "likely" to know, rather than "will" know. There is also the possibility they can be maliciously wrong, if there is money or some other incentive involved.
Conversely, a politician is not likely to be right about science, especially since they always have some incentive to warp the truth. Note that this applies to all politicians, not just the ones on the left or the right. So, I will not pay any attention to what Bush or Gore say on global warming, but will instead look at what the scientists are saying (and where they are getting their funding). I will take a scientist's word over a political leader's.
Likewise, while slashdotters are much more informed than politicians on average, we're hardly experts. When someone here posts a one-line rebuttal to a long and detailed scientific paper, I tend to assume it's the scientists who know what they're talking about, not the slashdot poster. When someone here posts a detailed analysis of the situation, preferably with some sound external links, then I take them seriously.
Nature dislikes it when you anthrpomorphasize her:-)
And on a more serious note, you do realize that bird flu and SARS are far less serious than the black death in the middle ages and the 1918 flu epidemic right? Disease organisms that kill their host die themselves in the proccess, so there is a strong evolutionary pressure against fatal epidemics. If we were all going to die of some horrible plague, we'd have done so already. Plagues can cause great human suffering, but aren't likely to cause extinction, and even mass die-offs are unlikely.
There is no way that a few puny upstart viruses will solve the overpopulation problem. Birth control would, but those methods are the product of wealthy societies, and most of the current population growth is in 3rd world countries where people don't have the means to avoid conception. Plus, many of those same countries have strong religious objections to birth control, or strong cultural pressure to have large families, so even if they had the means to avoid overpopulation, they might not use them.
The mods probably saw "cooling trend" and "1970" and assumed the poster was bringing up the tired old arguement that we used to think the earth was headed into a new ice age.
The arguement usually goes that before 1970 we thought there was a new ice age coming, due to a global cooling trend. This is usually followed by the arguement that climate scientists don't know what they're talking about, and that man-made global warming is a myth. What this "talking point" ignores is that the so-called "new ice age" never had much scientific credibility; it is primarily remembered because it had a great deal of press coverage. Further, IIRC the global warming hypothesis goes back to at least 1968.
In every single/. discussion involving climate change, the above arguement is made as a talking point by people who dislike the notion that humans are affecting global temperature. So, after a while I suspect that moderators get a wee bit trigger happy whenever someone mentions the words "cooling" and "1970" in a post about climate change.
Note that the GP's point is valid, as there was an observed period of lower temperature 30 years ago (which is what sparked all the media speculation regarding a new ice age). However, I'm sure the scientists who did this study took that trend into account, and in any case the cooling trend was both brief and comparatively small.
Eh, the way I see it, that's only really a problem if you want to use the cells for general purposes.
If you use your own cells to repair your own bodily tissues, then the new tissue will have virtually the same age as the old one. Compare that to the problems associated with tissue rejection in transplants, which using your own cells would avoid, and the adult stem cell approach comes out ahead.
Plus, the Russians launched several probes to Mars under the USSR, though they did have a high failure rate. So you're correct only in saying they haven't gone in this decade. Selecting your time period to exclude the earlier missions doesn't make much sense - it's like ignoring the Apollo program in the US because it happened thirty to forty years ago.
The US program isn't a major one at the moment. That could change, and if it does then either international competition or cooperation could occur, but right now NASA isn't a major feature in the public mind, and much of its budget is taken up by the shuttle program and ISS (neither of which has much to do with any Mars program). It's not like Russia and China are racing America to get a probe there and back again, since the US hasn't expressed any similar intent.
Sure, the US could push for a multilateral approach to space exploration. Now, stop and think about the current state of affairs in the 'states and you'll see why this isn't likely to happen.
Ths US has a massive deficit, and little actual interest in spaceflight. I have no doubt that NASA could get to Mars and back again, if they had both the budget and the full support of congress and the general public. But in the absence of either, there is little room for new spaceflight programs in their agenda. And even getting an unmanned probe there and back would be a challenge, since it essentially doubles all the costs associated with fuel (not just monetary costs, but weight considerations as well).
This isn't about an adversarial approach to space exploration; China and Russia aren't competing with America. For there to be competition, the US would actually have to have a similar program in place. They might see it as a space race, or national pride, or what have you, but they aren't actually trying to beat anybody.
...much as a coma patient is just another part of the hospital.
...except that hospitals aren't organisms, they're institutions dedicated to caring for or curing those in need. By your arguments, if a women is to a fetus as a hospital is to a patient, doesn't that mean her only purpose is childbearing? Because I think you'll find that outlook doesn't really fly these days...
Plus, a coma patient (or rather that patient's relatives, or the gov't in social helth care systems) are paying the hospital to keep the coma patient alive. They're not a burden on the hospital, rather the opposite - patients keep the doctors gainfully employed.
I'd say the comparison is invalid. I'm not disagreeing with you on the nuanced point, but the analogy you're using to illustrate it is a strawman.
Well, just to point out the obvious, humans (and primates more generally), aren't the only group that establishes pair bonding. Yet the vast majority of species that reproduce via sex mate back-to-front (obviously this only counts species that actually mate). If sex needed to be a certain way to cement relationships, then that particular way wouldn't be largely confined to humans.
And the current configuration for human anatomy supports both back-to-front and front-to-front mating, so it can't be a question of one form of mating being more normal for humans than the other. We aren't constrained to one or the other.
The particulars of human hip configuration and child birth are well known; we have far more problems with this than most live-birthing species. One of the evolutionary constraints humans face (in fact, one of the places where evolution has equipped us very poorly) is in bearing children. By being upright standing we're forced to have comparatively narrow hips, and due to our intelligence our heads are quite large at birth. Trying to fit a large skull through a narrow opening is not easy, for either the mother or the baby.
To make birth easier, we've evolved along certain anatomical lines. Human infants are born smaller relative to the size of human adults than is the case with other primates, and take a relatively long time to reach maturity as a result. Infantile skulls are softer and not fully fused when they're born, allowing for a certain amount of compression. Women have wider hips than men, in order to make room for a child's skull during birth. All these things make human birth possible, but even then human females have a much harder time of it than females of most other mammalian species.
The generally accepted explanation for these problems is that humans developed from a non-upright standing ancestor to our current stance in a relatively short time period, and we never fully adapted to standing upright. There are dozens of anatomic holdovers from an earlier aboreal form that get in the way of many aspects of human life, or else merely serve no useful function.
All of this makes it difficult for me to believe that women would develop any sort of vaginal configuration for the purposes of mating that wasn't optimized for giving birth. Evolution would select for the best configuration suited to surving childbirth and producing children with larger brains.
This doesn't mean that we don't also pair bond from mating front-to-front, it just means that the pair bonding is more of a bonus or side effect than anything else. Ie, it's a consequence, not a cause.
The human vagina (so I've read) is positioned to encourage people to have sexual intercourse facing each other, cementing the pair bond between them.
Sounds like bad science to me. The human vagina is positioned where it is because humans are upright standing bipeds.
The entire hip structure of a human adult is configured for walking on our hind legs with our spine perpendicular to the ground, and since the birth cannal runs through the hips in human women, there can be no other vaginal configuration. Remeber that the primary function is childbirth, not sex.
If the opening were facing further forward or backward, then more complications would arise during birth (which is already very difficult for humans due to the size of our offspring's skulls at birth). Note that this configuration is unique to humans and hominids; other primates do not have the same hip configuration (as they do not walk upright all the time), and other bipedal species do not have the same upright stance as we do.
Emotional bonding may be a consequence of this, but it is not a cause. Furthermore, it is quite possible to have sex with a women without being face to face - there are far more positions than just the missionary one, many of which are back to front.
Slashdot Mirror
And on the eighth day God said "let there be design by committee".
Of course, due to zoning laws, the mammalian committee ended up running a toxic waste pipe through a playground. Damn civil engineers...
The objective criteria you mention must take the organism's habitat into account. You know this, I know this, but the problem is that many other people don't know this. The phrase "survival of the fittest" without the qualifier is what most people understand evolution to be, as if there were some measure of fittness that wasn't relative and subjective. This in turn leads to all sorts of misunderstandings about how evolution works, the most disturbing of which can be seen in 19th century social darwinism.
Plus, it's worth noting that not all evolutionary progress pays off. To get back to your own counterpoint about amphibious fish surviving when the pond dries up, those same fish would be a less successful species right up until the point where the water based life dies. They'd probably be a marginal species that outlives the specialists by a stroke of luck.
This is where genetic diversity matters - you never know what sort of arraingment is going to work best in the future. Often the generalists outlive the specialists, and humans are definately in the specialist category (we're completely dependant on man-made tools to survive).
As for us humans, I would argue that our environment is a technological one, and that we only consider ourselves highly evolved because we're basing our criteria on ourselves. In other words, our survival strategy is toolmaking, so we're biased in favour of that strategy over any other. I don't think it's possible to look at what we've evolved for objectively, anymore than an individual can judge themselves impartially. And it's way to easy to get into circular reasoning.
Long version:
http://en.wikipedia.org/wiki/Evolution_of_the_eye
Short version: We now know that patches of photoreceptive cells can develop without the surrounding structure of the eye. Furthermore, having minimal sight is substantially better than no sight whatsoever, so even "half an eye" is workable from an evolutionary perspective.
So incremental development is possible, beginning with a retinal precursor, and slowly developing layers of complexity that give rise to the various types of eye (for example, human eyes and compound eyes, which are dissimilar in configuration, but serve the same function).
Yeah, but that doesn't excuse changing the meaning of the original quote. This is like taking "John went to the store" and altering it to say "John went to the [book] store", when John actually went to the video store. My point that organ =! organism stands.
True, but the ability to adapt to alien (and I use the term very generally here) environments is not what our survival strategy entails.
Our survival is essentially rooted in toolmaking and inventiveness. There are other examples of species that employ tools, but none to the same degree that we do. Virtually everything that we need to survive, and everything that sets us apart, is rooted in this adaptation.
This is not the survival strategy of a generalist, it's the way of a specialist. We've got all our eggs in one basket. That basket has paid off in many unique and useful ways, which allow us to do things like survive in environments that are radically different from the ones we initially evolved in, but fundamentally we're still specialized.
The environment we're fit for is a technological one, rather than a geographic one.
Does this make us unique? Yep, but that's hardly an unusual affair for specialized animals. Does that make us intelligent? Hell yeah, but then we only consider intelligence/sapience so important because it's the only shtick we've got. There's a quote that goes something like "I used to think the mind was the most interesting part of a person - then I thought 'hey, wait, look who's telling me that'", which sums up our emphasis on brains quite nicely.
You do realize that the quote didn't say "organism", right? It specified "organ", which is a major difference in biology. Organs have pretty much zero to do with gene count, and in any case single celled organisms don't really have organs in the normal sense of the word.
What Darwin was saying was essentially that if an organ were encountered that could not have developed incrementally, then that would disprove his theory. People have tried to show that the eye meets this criteria, but we now know that light sensing organs can develop incrementally. Wings have also been brought up as a potential arguement, but are counteracted by examples of wing-like structures that serve some intermediate purpose other than flight.
Plus, gene count does increase incrementally, so even if Darwin had used the word organism, your answer would still be "no". Gene count is really pretty irrelevant as a measure of complexity, and in any case is easy to increase slowly over time with mutation.
Well, the main problem is the public perception that evolution produces "superior" species. This is rooted in a 19th century mentality that held to a notion that there were "upper" and "lower" life forms (which incidentally is a view that predates natural selection by a good many years, and is arguably not confined to the 19th century). When you talk about the views held by the average non-scientist regarding evolution, the most common perception is "survival of the fittest", with the implication that those that survive are somehow better objectively.
In actuallity, survival of the fittest implies fittness for a certain environment only. To borrow someone else's analogy, you can have the best gills in the pond and you'll still die off with the rest if the pond dries up.
The problem is really the human ego; we have an enourmously hard time accepting the idea that humans aren't innately special. We're intelligent, certainly, and we're unique, but then again every species that has a highly specialized survival strategy is unique.
Seamus
Well, at least I used the right letters, even if they are out of order...
:-) )
(besieds, lteter odrer deons't maettr, rihgt?
I find it distubing and hilarious that Anal Sex rates above Ghandi, but below Jedi (check for yourself, that's how they're ranked)....
Where did I say scientists are infallable? I didn't, and I dislike the accusation.
My point was more that a scientist with years of schooling and anywhere from years to decades of practical experience (and the wherewithal and curiosity to keep at it) is likely to know what he or she is talking about in their field. I allow for the possibility they are wrong, hence "likely" to know, rather than "will" know. There is also the possibility they can be maliciously wrong, if there is money or some other incentive involved.
Conversely, a politician is not likely to be right about science, especially since they always have some incentive to warp the truth. Note that this applies to all politicians, not just the ones on the left or the right. So, I will not pay any attention to what Bush or Gore say on global warming, but will instead look at what the scientists are saying (and where they are getting their funding). I will take a scientist's word over a political leader's.
Likewise, while slashdotters are much more informed than politicians on average, we're hardly experts. When someone here posts a one-line rebuttal to a long and detailed scientific paper, I tend to assume it's the scientists who know what they're talking about, not the slashdot poster. When someone here posts a detailed analysis of the situation, preferably with some sound external links, then I take them seriously.
Nature dislikes it when you anthrpomorphasize her :-)
And on a more serious note, you do realize that bird flu and SARS are far less serious than the black death in the middle ages and the 1918 flu epidemic right? Disease organisms that kill their host die themselves in the proccess, so there is a strong evolutionary pressure against fatal epidemics. If we were all going to die of some horrible plague, we'd have done so already. Plagues can cause great human suffering, but aren't likely to cause extinction, and even mass die-offs are unlikely.
There is no way that a few puny upstart viruses will solve the overpopulation problem. Birth control would, but those methods are the product of wealthy societies, and most of the current population growth is in 3rd world countries where people don't have the means to avoid conception. Plus, many of those same countries have strong religious objections to birth control, or strong cultural pressure to have large families, so even if they had the means to avoid overpopulation, they might not use them.
The mods probably saw "cooling trend" and "1970" and assumed the poster was bringing up the tired old arguement that we used to think the earth was headed into a new ice age.
/. discussion involving climate change, the above arguement is made as a talking point by people who dislike the notion that humans are affecting global temperature. So, after a while I suspect that moderators get a wee bit trigger happy whenever someone mentions the words "cooling" and "1970" in a post about climate change.
The arguement usually goes that before 1970 we thought there was a new ice age coming, due to a global cooling trend. This is usually followed by the arguement that climate scientists don't know what they're talking about, and that man-made global warming is a myth. What this "talking point" ignores is that the so-called "new ice age" never had much scientific credibility; it is primarily remembered because it had a great deal of press coverage. Further, IIRC the global warming hypothesis goes back to at least 1968.
In every single
Note that the GP's point is valid, as there was an observed period of lower temperature 30 years ago (which is what sparked all the media speculation regarding a new ice age). However, I'm sure the scientists who did this study took that trend into account, and in any case the cooling trend was both brief and comparatively small.
Eh, the way I see it, that's only really a problem if you want to use the cells for general purposes.
If you use your own cells to repair your own bodily tissues, then the new tissue will have virtually the same age as the old one. Compare that to the problems associated with tissue rejection in transplants, which using your own cells would avoid, and the adult stem cell approach comes out ahead.
Number that have been there and back: 0
Plus, the Russians launched several probes to Mars under the USSR, though they did have a high failure rate. So you're correct only in saying they haven't gone in this decade. Selecting your time period to exclude the earlier missions doesn't make much sense - it's like ignoring the Apollo program in the US because it happened thirty to forty years ago.
The US program isn't a major one at the moment. That could change, and if it does then either international competition or cooperation could occur, but right now NASA isn't a major feature in the public mind, and much of its budget is taken up by the shuttle program and ISS (neither of which has much to do with any Mars program). It's not like Russia and China are racing America to get a probe there and back again, since the US hasn't expressed any similar intent.
Sure, the US could push for a multilateral approach to space exploration. Now, stop and think about the current state of affairs in the 'states and you'll see why this isn't likely to happen.
Ths US has a massive deficit, and little actual interest in spaceflight. I have no doubt that NASA could get to Mars and back again, if they had both the budget and the full support of congress and the general public. But in the absence of either, there is little room for new spaceflight programs in their agenda. And even getting an unmanned probe there and back would be a challenge, since it essentially doubles all the costs associated with fuel (not just monetary costs, but weight considerations as well).
This isn't about an adversarial approach to space exploration; China and Russia aren't competing with America. For there to be competition, the US would actually have to have a similar program in place. They might see it as a space race, or national pride, or what have you, but they aren't actually trying to beat anybody.
Plus, a coma patient (or rather that patient's relatives, or the gov't in social helth care systems) are paying the hospital to keep the coma patient alive. They're not a burden on the hospital, rather the opposite - patients keep the doctors gainfully employed.
I'd say the comparison is invalid. I'm not disagreeing with you on the nuanced point, but the analogy you're using to illustrate it is a strawman.
The sewage system is not a big truck! It's a series of tubes!
I think the Goatse man can claim prior art...
Well, just to point out the obvious, humans (and primates more generally), aren't the only group that establishes pair bonding. Yet the vast majority of species that reproduce via sex mate back-to-front (obviously this only counts species that actually mate). If sex needed to be a certain way to cement relationships, then that particular way wouldn't be largely confined to humans.
And the current configuration for human anatomy supports both back-to-front and front-to-front mating, so it can't be a question of one form of mating being more normal for humans than the other. We aren't constrained to one or the other.
The particulars of human hip configuration and child birth are well known; we have far more problems with this than most live-birthing species. One of the evolutionary constraints humans face (in fact, one of the places where evolution has equipped us very poorly) is in bearing children. By being upright standing we're forced to have comparatively narrow hips, and due to our intelligence our heads are quite large at birth. Trying to fit a large skull through a narrow opening is not easy, for either the mother or the baby.
To make birth easier, we've evolved along certain anatomical lines. Human infants are born smaller relative to the size of human adults than is the case with other primates, and take a relatively long time to reach maturity as a result. Infantile skulls are softer and not fully fused when they're born, allowing for a certain amount of compression. Women have wider hips than men, in order to make room for a child's skull during birth. All these things make human birth possible, but even then human females have a much harder time of it than females of most other mammalian species.
The generally accepted explanation for these problems is that humans developed from a non-upright standing ancestor to our current stance in a relatively short time period, and we never fully adapted to standing upright. There are dozens of anatomic holdovers from an earlier aboreal form that get in the way of many aspects of human life, or else merely serve no useful function.
All of this makes it difficult for me to believe that women would develop any sort of vaginal configuration for the purposes of mating that wasn't optimized for giving birth. Evolution would select for the best configuration suited to surving childbirth and producing children with larger brains.
This doesn't mean that we don't also pair bond from mating front-to-front, it just means that the pair bonding is more of a bonus or side effect than anything else. Ie, it's a consequence, not a cause.
The entire hip structure of a human adult is configured for walking on our hind legs with our spine perpendicular to the ground, and since the birth cannal runs through the hips in human women, there can be no other vaginal configuration. Remeber that the primary function is childbirth, not sex.
If the opening were facing further forward or backward, then more complications would arise during birth (which is already very difficult for humans due to the size of our offspring's skulls at birth). Note that this configuration is unique to humans and hominids; other primates do not have the same hip configuration (as they do not walk upright all the time), and other bipedal species do not have the same upright stance as we do.
Emotional bonding may be a consequence of this, but it is not a cause. Furthermore, it is quite possible to have sex with a women without being face to face - there are far more positions than just the missionary one, many of which are back to front.