From the editorial in the current issue of Scientific American:
In retrospect, this magazine’s coverage of so-called evolution has been hideously one-sided. For decades, we published articles in every issue that endorsed the ideas of Charles Darwin and his cronies. True, the theory of common descent through natural selection has been called the unifying concept for all of biology and one of the greatest scientific ideas of all time, but that was no excuse to be fanatics about it.
Where were the answering articles presenting the powerful case for scientific creationism? Why were we so unwilling to suggest that dinosaurs lived 6,000 years ago or that a cataclysmic flood carved the Grand Canyon? Blame the scientists. They dazzled us with their fancy fossils, their radiocarbon dating and their tens of thousands of peer-reviewed journal articles. As editors, we had no business being persuaded by mountains of evidence.
Read the whole thing. (Via Pacific Views).
What a fantasticly funny editorial. Thanks for posting it up.
Does this mean you are trying to start an evolution debate (is that an oxymoron?)? If so can we invite some of the crew to our right from the Terri Schiavo debate over for some lively discussion. I’d love to play. Actually, I’d love to (and this is my favorite new verb) nonreligiousevidencize, that is provide non-religion-related factual or theoretical arguments in favor of a rational argument.
Let me just throw out my favorite evolutionary twist. Why is homosexual behavior observed in so many species and what are the reasons for the evolution of this trait? I won’t go further until there is some comment, but, again, it would be fun!!
Dr. Ted, I love evolution debates !
Is it accurate to portray evolution simply as “survival of the fittest”?
Brad,
I believe the “survival of the fittest” quote is one of the most often ill-used quotes concerning evolution. It is correct, but the way in which it is correct is often misconstrued. “Fittest” in the evolutionary sense does not point to a particular trait, like strength or cunning, but rather to a certain organism’s “fitness” to its environment.
As I understand it, this is just a simple way of saying “those organisms with the traits most suited to their environment will happen to survive”. Those that best “fit” their particular circumstances. And since they survive, they pass those traits on to their offspring.
I hope that made some sense.
I agree Zenmaster ( said Grasshopper), I understand the phrase. Where I was headed with that, is that I don’t believe that phrase can answer all of the questions out there.
First, I should state my position. I have always been an evolutionist. However, I have always had a question in the back of my mind in that, it doesn’t always work for me.
For example, It is my understanding that over time, humans are gradually losing their appendix. On the surface it makes sense because it really isn’t used for our survival. However, How does having a smaller appendix, or lack of one, make us better able to survive as a species? Do people with smaller appendices somehow have more children? Or do their children have a greater life expectancy etc…
YES!! Others have arrived.
Brad, I do not “like” the term survival of the fittest. I do agree with Zenmaster’s interpretation, problem is it can mean so many things, but then again, evolution, other than being a unifying principle, can mean so many things as well. I much prefer natural selection, meaning that random changes in the genome are often “selected” because they give an organism an advantage in a given environment. This is largely what Darwin studied in the Gallapagos and is also where the bulk of literature on the topic of evolution has been published.
As for the appendix, that is one of those funny things about natural selection. At one point the organ became important (and still is to many organisms) because the combination of genes that evoloved to make the appendix (that is a MASSIVE oversimplification btw, but I don’t know how else to say it) gave the organism an advantage (I think I also just created a chicken and egg argument here, but hopefully you see where I am going). Then, at some point, the appendix became rather irrelevant to physiology due to other adaptations, but it never became an advantage not to have one (I guess appendicitis never has been a big evolutionary pressure). Hence, the appendix is a holdover from our evolutionary past that now has no purpose. While I know of no other example of this in human organs, and don’t think there is one, there is redundancy in the genome that might or might not still be useful, and there are almost certainly proteins encoded in our genomes that are all but useless to us now, but may have been absolutely essential at one time.
I agree with all of that.
However, Why would natural selection, evolution, or survival of the fittest ( whatever we may choose to call it ) not just leave the appendix there as not needed. What drives it to slowly fade away? There is no “evolutionary pressure for it to go away, therefore my thought is that it would stay and just be “extra anatomy”. It doesn’t give us an advantage, but yet it doesn’t give us a disadvantage. Is there something other than “advantage / disadvantage” that figures into the evolutionary process?
Perhaps, with the appendix, it is more like this: folks who have an appendix no longer survive long enough to reproduce than those without. Due to the same set of circumstances (that we no longer consume a high-cellulose diet) folks who lack an awesomely functional appendix no longer fail to survive long enough to reproduce, and so more bad-appendix genetics make it out there.
So, to go back to the fitness test an appendix no longer makes one fit to the environment, so the likelyhood that a person will reproduce is no longer influenced by how functional their appendix is.
The phrase “Survival of the fittest” was never ONCE uttered by Charles Darwin. That phrase was popularized by Herbert Spencer, who was trying to push for Social Darwinism (or a really bad excuse for robber barons to exploit the labor and do it with a clear conscious). Darwin stated that the more adaptable a given species was to a changing envirnment, the more likely that the same genes would be passed on to the offspring, so that the trait would be strengthened if the envirnment stayed the same or similar.
The appendix argument is interesting: at some point, we needed an appendix. We don’t really need one anymore, we just haven’t gotten rid of the one we have because it’s not really pressing to NOT have it. But it’s slowly getting smaller because less and less of the human resources have been diverted to it.
Or at least this is what I gleaned from my biology 250 class. (I got an “a” that’s got to mean something)
Interesting Antigone ! So, the “evolutionary pressure” to get rid of the appendix ( while low pressure) is due to resources being utilized elsewhere? That certainly sounds plausible.
I find human evolution ( going forward) to be a good test of the evolutionary concept, because our biology has much less to do with our survival in modern times. We have no need for heightened senses, great speed or strength etc…We just need to have a good supermarket nearby.
First, I very much agree with Doc Ted and Antigone that the “fittest” thing is not the most useful language to discuss this with.
Brad,
I think it sort of confuses the issue to talk about human evolution as “going forward” , though. Evolution is not a teleological process, that is, there is not really any goal that it is shooting for.
However, I may be misunderstanding your point a bit. I do think observations about how people’s increasing dependance on technology shapes what traits get selected for.
Also, when thinking about issues of sexual selection, I wonder what ultimate effect all of the available ways to reshape our bodies with plastic surgery and whatnot effect the distribution of traits.
Um, I mean “observations about how people’s increasing dependance on technology shapes what traits get selected for are super interesting“.
I need more gooder proofreading.
I agree it is not the best term for ongoing discussion, I simply felt it was the best phrase for the point I was making.
I did not mean to imply evolution had a goal, merely that it is ongoing.
As for plastic surgery, that is another interesting angle to look at. For instance, men have been biologically attracted to large breasts. However, with implants, that same biological attraction can then be directed towards a woman who naturally would have smaller breasts, therefore “inadvertantly” the genes for the smaller breast is what gets passed on.
god damn it: NO
stop it, right now.
just because for as long as you can remember, big breasts have been the vogue doesn’t make it biological.
historically, smaller breasts were considered attractive.
yes, there are stupid “evolutionary” arguements for the big breasts one being attractive (milk, therefore, fertile) but the same can be said of small breasts (developed into maturity but not lactating yet, which means not pregnant, which means conception is possible)
yes, everything HAS a biological explanation. but as we were not physically around to watch said evolution and take records, any speculation as to specifics is just that, speculation.
and if you’re going to waste time speculating on evolution, why not pick something that has actual points of scientific curiousity behind it, like “where the hell wings came from?”
wings have evolved separately on at LEAST 3 different occations (insect wings, avian wings, bat wings)
and since half evolved wings are nigh useless, it takes some serious head scratching to come up with a solution.
Karpad,
Avian wings might have come from dinasour wings, which might actually be the same as avian wings… who knows?
As for big breasts and what is attractive for sexual selection, while it is a rather blunt and politically incorrect thing to say, it has to do with who reproduces more, which is very important. I don’t know if women with bigger breasts reproduce more or if they tend to get more “fit” males to reproduce with them. Attractiveness of physical features is certainly altered by social context, but alot of it is constant despite cultures or fads. Take for instance facial attractiveness. While there are aspects of this that are altered by culture, if properly controlled for in experiments, people tend to find certain kinds of faces more attractive than others almost without exception. Also, take the example of display feathers in birds. They make certain males extremely susceptable to predation but they are nonetheless “selected” becasue they provide a huge advantage in mating.
As for social Darwinism, it should not be called that, since it also had nothing to do with Darwin, other than the inventors had read him. For anyone interested in a great debunking of these concepts check out the late, great Steven J Gould (especially The Mismeasure of Man).
BTW, I’m removing the Dr from the front of my name (just “Ted” is still me). I feel really pretentious (sp?) in this forum with that one.
What I am really interested in is how do we get evolution back into the curriculum of our schools? The demonization of Darwin really bothers me, and it bothers me more that the kids of today are largely not learning about the concept, which started with Darwin, as part of their scientific advancement. The ideas of Darwin, and the findings of Gregor Mendel, are really the 2 most fundamental concepts behind all of modern biology, yet many junior and high school kids are lucky if they get any concrete information on these principles. This is especially scary to me because the concepts of Darwin have been adopted by nearly every discipline to explain everything from market behavior to technological advancement and political policies, yet its not taught.
Ted, Karpad is correct. Big breasts on women on are not universally found to be attractive across cultures even today. In some cultures, “Your mother has large breasts, ” is used as an insult. As to faces that are found to be attractive across cultures, that has to do with symmetry. That is to say that symmetrical faces are universally found to be more attractive than non-symmetrical faces. Nose size, eye color, skin color, lip size, forehead size are not part of that equation. Drop it.
Thank you Karpad for pointing out the myth.
A half devoluped wing might be a really good something else. What I could think of would be better balance for running, or stabalization for jumping a half-wing may be very very useful.
Excuse me…I was making a point about plastic surgery and it’s potential effects on the evolutionary process. I used breasts in the example because it was a simple, common, well known situation. The point was, and is valid, that different types of cosmetic alterations may have the result of different traits being passed on.
karpad, without much effort at all, I can think of several possible benefits of “half-evolved” wings. Slowing descent when jumping from trees to escape predators, gliding, aiding swimming, and even intimidation (by appearing larger) of potential predators or breeding rivals are some.
Hey Jake Squid, I didn’t say Karpad was wrong, just trying to point out that sexual selection is an important part of natural selection. As for faces I am well aware of symmetry. In fact, I have published a paper on the subject (O’Toole et al., Image and Vision Computing 1998) in which we looked at the aspects of averagering different characteristics of faces (shape vs. texture) and how they effect perceptions of attractiveness. Averaging, which makes any given face more symmetrical by definition, also changes the size of features moving them more toward the mean depending on the number of morphs (or averages). The more morphs we did, the more attractive the faces got. We did not control for feature sizes, but we did find that morphing only texture gradients had little effect while morphing size strongly affected perceptions of attractiveness. There is a huge literature out there on facial attractiveness across cultures and between races and there is lots of evidence that there are certain features of faces, of which symmetry is one, that make faces more attractive. There are exceptions though. The best one I can think of is jaw size in men. Big square jaws almost always push both men and women to rank a man’s face to be more atractive. Not quite sure what that means for symmetry but it goes against the averageness argument.
Here is another good one for discussion: from this weeks issue of Nature:
Sex increases the efficacy of natural selection in experimental yeast populations
MATTHEW R. GODDARD*, H. CHARLES J. GODFRAY & AUSTIN BURT
ABSTRACT
Why sex evolved and persists is a problem for evolutionary biology, because sex disrupts favourable gene combinations and requires an expenditure of time and energy. Further, in organisms with unequal-sized gametes, the female transmits her genes at only half the rate of an asexual equivalent (the twofold cost of sex). Many modern theories that provide an explanation for the advantage of sex incorporate an idea originally proposed by Weismann more than 100 years ago: sex allows natural selection to proceed more effectively because it increases genetic variation. Here we test this hypothesis, which still lacks robust empirical support, with the use of experiments on yeast populations. Capitalizing on recent advances in the molecular biology of recombination in yeast, we produced by genetic manipulation strains that differed only in their capacity for sexual reproduction. We show that, as predicted by the theory, sex increases the rate of adaptation to a new harsh environment but has no measurable effect on fitness in a new benign environment where there is little selection.
Ted,
Have you got a link for that article? I’d like to read it, I’m always interested in more details on subjects that interest me. And please excuse me for misreading you.
No problema, I just really don’t want this to turn into the Terri Schiavo post and just wanted to clarify straight away that I don’t think anyone here is wrong about anything.
Here is the link letters to nature
there is also a news and views article about the manuscript.
I don’t think you will be able to access it, though, as I have an institutional subscription, unless you are also sitting in a University or Library. Nature is widely available in bookstores and news stands though. It is the March 31st issue. Someone put up some site that gives out registrations for sites that I cannot find again, BUT, they had one for http://www.nature.com.
Jake Squid,
Did you mean the Nature article? Just realized maybe you meant the O’Toole et al., on which I am an author. Here is a link to that article (which was 1999 not 1998 as I mentioned above). I cannot even access that one!! But you can read the abstract. I don’t even have a reprint, and my library has no holdings on the journal. MADNESS!!
For anyone serious about learning more about evolution, I would highy recommend the talkorigins.org archive. They cover many of these topics in great detail and scientific answers to many questions can be found there.
Here’s a readable link to Ted’s article about facial imaging and attractiveness.
And here’s a readable link to the article about sex and yeast.
I just wonder whther the editorial was written in the expectation that some readers would be studying it on April 1st.
Surely not!
About my article… If anyone actually does read it I would strongly urge you to pay the most attention to the references and go look up some of those people’s more recent works. I did this when I was an undergrad and I have not kept up (I’m a molecular person now). Also the first author has a number of excellent articles out there on face recognition (anyone looking to do a PhD in face perception couldn’t hope to find a finer mentor than her). This manuscript was mostly about fancy computer programs for face manipulation with some application for perception, which made it a bit more interesting.
Brad, your point about plastic surgery is an interesting one; however, we humans reproduce on a glacial time scale and it is unlikely that we would see any evidence of it unless 1) humans, in mass numbers, continued to have plastic surgery for eons and 2) they all did it before they started reproducing (to cover up or alter some trait). In the same way, it is way to early to judge how our changing our environment, tech advances and all will influence our evolution. We will likely be manipulating our own genome long before any of the environmental pressures will have an effect on a genetic scale (or the environment will wipe us out altogether),
Ted, That is a great point, we will likely be manipulating the genome. At which point we may be trying to guess what nature’s next course of action might be, and then manipulating it to speed it up or avoid it altogether etc…
Can you imagine the bloglines when THAT starts happening !
If you want to read an avowed Darwinist’s explanations of some of the issues already brought up here, try the books of Richard Dawkins.
(The Selfish Gene, The Blind Watchmaker, Unweaving the Rainbow, The Extended Phenotype and others).
I’m sorry to be too lazy to look it up, but one of these has a line of argument about the evolution of the eye which parallels closely, in principle, the remarks about wings. And while I don’t remember anything about breasts, there’s an interesting discussion of long tails on some birds.
Whether or not you find yourself persuaded by Dawkins, I believe you would find that he is a really good writer and will give you a lot to think about.
And although Bill Bryson’s “A Short History of Nearly Everything” covers plenty of other subjects too, it’s worth a read too.
I think it’s possible that once the enormous timescales over which evolution is said to have occurred are appreciated, then looking for anything very significant (in the evolutionary sense) in plastic surgery or modern medicine will not be a very fruitful line of enquiry.
Whoever it was who coined “survival of the fittest” at least gave dramatic emphasis to what might otherwise have seemed a dull explanation.
“Things that survived a little bit better than things that did not survive quite so well, tend to be the things that, having survived, exist” is not exactly snappy is it?
Brad, it would be crazy. But to go off point a bit, we may eventually find that it is our only option. I don’t mean to support this idea, but it does run through my head on occcassion. WHat if the environment continues on its current way and eventually become inhospitable? Imagine a scenario where the ozone layer all but goes away. Some species could survive this, and the rapidly reproducing ones would likely cope as it happened, but we would not. Would we just let ourselves die off, or a few survive that would be lucky enough to have an adaptation and start a new species or subspecies (though it need not be one, but could). What would come first, a fix for the lack of ozone, colonization of a new planet, or genetic manipulation to make us fit to survive the constant blast of radiation? My guess is that we could find a way to manipulate the next generation so they could be able to survive in that environment before we could accomplish any of the others. Moreover, I doubt if all of the Earth would reach a consensus and at least some would chose that alternative.
Perhaps that is a poor example, but I think you can get my point. Either way, these are questions we will eventually face if for no other reason than we will have the technology to do so in the future (on that I have no doubt).
Across, it won’t be fruitful in terms of yielding any “actionable” information. However, striving to know the unknowable is itself fruitful.
I also endorse Richard Dawkins. Daniel Dennett has some interesting books too from a more philisophical perspective. Konrad Lorenz’s Solomon’s Rings is one of the finest works on natural selection ever written (with lots on long tails of birds). Stuart Kauffman’s At Home in the Universe is also quite good. But nothing can replace good old Darwin himself!
Not to be annoying here or anything, but is there any evidense FOR Intelligent Design? I’ve been purusing the websites, but I have yet to see any experimentation, or anything that holds up to the scientific method.
I’ve always preferred Stephen J Gould to Dawkins, myself.
On breasts, none of our near neighbors (the other primates) have noticeable breasts, so there is the question of why do we have them. Their direct utility is unclear (enlarged breasts are not required for milk production) and they can be a hinderance and, large or small, they seem to be eroticized to some degree in many cultures. Added together, that does suggest the possibility that breasts may have been developed at least in part by sexual selection. Of course, it is also possible that enlarged breasts are a response to some other human feature (such as short faced babies). However, visible physical features which imply a greater likelihood of successfully reproducing are often the objects latched onto by sexual selection mechanisms, so it is possible that both mechanisms are in play. Since small breasted women (whose breasts are still much larger than chimpanzee breasts) don’t accidentally smother their babies, it is clear that large breasts (within the human range) do not provide an advantage in feeding short faced babies, and they are definitely much more of a hinderance.
One other thing, humans have lost estrus, lost our sense of smell, and taken to covering our genitalia, so features that make it possible to distinguish men from women quite possibly have a selection advantage all by themselves.
One thing to note about sexual selection, the preference that drives the sexual selection does not need to be hereditary. Cultural preferences are perfectly capable of creating sexual selection. If there is a strong sexual preference (sufficiently that people who don’t meet the criteria are significantly less likely to breed) that lasts for a meaningful length of time (relative to the difference in rate of breeding) where the thing preferred is genetically determined, then sexual selection will occur. For example, if a population of people decided that only blue eyed people would be allowed to breed, it would only take a single generation of this rule being thoroughly enforced for the subsequent population to be entirely blue-eyed. If only blue eyed men were allowed to reproduce, it would take longer, but still would have a substantial effect. This is also true in non-humans (there was recently a very nice review article (in Science, I think) about the effects of public information in evolution that talked about this effect on sexual selection in birds, I can try to track it down if anyone is interested).
Please do track it down Charles, I missed that one.
ANTIgone…I am intrigued by intelligent design, but so far, like you, I haven’t seen anything scientific. But, inherently, it may not be possible to do much scientifically with it.
I understand that it is more, sort of, the default position. Sort of like, if you see a strange object in the sky, and cannot explain it as an airplane, then it MUST be an alien spacecraft.
Brad and Antigone,
If you see any “scientific evidence” for intellegent design you would be the first. It is exceedingly difficult to design experiments to test ideas that are unknowable because they involve powers that exist outside our realm. Moreover, intellegent design, as an idea, is fluid since it cannot be rigorously tested, but any evidence in favor of “old earth” or natural selection can be discounted by new interpretations of what the “higher powers” have done to trick us or create illusions in our world. On the other hand, to take it on faith is the choice of the individual. I am always disturbed, though, by those that are incapable of having both faith and appreciation for scientific evidence, and in this case (natural selection that is) indisputable fact.
Ted, that was my point. It is one of those situations, that do not lend themselves to testing.
I happen to be one who does have a mixture of faith and science. My personal beliefs are that a higher power ( God , if you will ) put in place all of the raw materials etc…needed for life to start and to thrive etc….then, natural selection has taken over from there. A bit difficult to sum it up i a sentence or two, but there you go.
I can appreciate people believing in “intelligent design” and what-have-you, but my really beef begins when people say it is a “science”. To give equal time to the untestable hypothesis of ID and evolution is ludicrious, at least to me. But I don’t wish to believe everyone pushing for this in schools is simply trying to push an agenda. If it is a “faith” hypothesis, then it belongs in theology. If it’s a “science” hypothesis, then you can put it in a biology class.
Public Information and Evolution review article. I don’t know if this will be accessible if you don’t have a subscription to science.