Stephen Jay Gould

[Deleted member 133]

On many occasion, online, and in person, I have stated that I believe that Stephen Jay Gould is one of the finest authors / writers that the United States has ever produced. He is one of but a very few about whom I can honestly say that reading his works makes me a better person.

I refer you to wiki for the full bio http://en.wikipedia.org/wiki/Stephen_Jay_Gould.

I believe that he published 26 books in total, from 1977 to 2007. At least that's how many I have and I think I have them all!

With a few exceptions, most of these are collections of his monthly essays. They tackle a very wide range of subjects - from evolution, to the extinction of North American native peoples.

His theory of punctuated equilibrium, which I first read about in his 1989 book Wonderful Life: The Burgess Shale and the Nature of History, is what made me an immediate fan of his. It remains one of the most incredible and insightful books I have ever read. And it is very readable! (Sidenote: after reading the book, I was at a private function at the Smithsonian when a curator happened to see me looking with great interest at their public display of Burgess Shale fossils. We started talking and I mentioned Gould's book. She then offered (and I accepted) to take me to the drawers of fossils not accessible to the public, including many that were covered in Gould's book. It is because of experiences like that that we create bucket lists! But I digress...)

But the essay that has had, and can still have, the most profound effect on many people is what I call his essay on cancer. Here's a link to a copy http://cancerguide.org/median_not_msg.html. I have referred countless cancer patients to it. An amazing work.

I encourage anyone with a thirst for knowledge, and a desire for self-improvement, to read anything written by Stephen Jay Gould.

 

[Deleted member 133]

My bedside table has always got at least one Stephen Jay Gould book on it at any given time.

I'm currently reading a few pages a night from "An Urchin in the Storm - Essays about Books and Ideas."

In the essay "Misserving Memory" I came across this eloquent, accurate and amazingly understandable explanation of Darwin's natural selection:

...To Darwin, selection is the creative force in evolution. If I had to summarize the essence of Darwinism in a single concept, I would emphasize the directing power of selection. Genetic variation is raw material; it is "random" in the sense that mutations do not arise preferentially directed toward the production of advantageous traits. Adaptation is the result of natural selection, acting relentlessly across generations to accumulate favored variation through the differential success of fitter individuals in producing more surviving offspring. Evolutionists have waxed poetic in their metaphorical depictions of selection - Ernst Mayr compared it to the work of a sculptor, George G. Simpson to a poet, Theodosius Dobzhansky to a composer, Julian Huxley to Shakespeare himself. The comparisons may be stretched, or even silly, but they do reflect the essence of Darwinism - the creative power of natural selection.

The implications of the bit that I underlined really bring it all into focus, and strike at the heart of many of the misunderstandings about Darwinism.

Jeff

 

[PaulyT]

Or, illustrated another way:

 

[Botch]

Thanks for the tip, the last couple volumes I've read have been stinkers, need something good. :handgestures-thumbup:

 

[Huey]

Not discrediting evolution at all, because I firmly believe in it, but I am surprised we haven't been able to witness it with our own eyes in species that propagate profusely. You would think in species like fish and insects that have large amounts of offspring, there should mutations that happen quite frequently. But then again, maybe we have seen it when they find a new species from time to time.

 

[PaulyT]

Actually where we see it most is microbes, for example in antibiotic resistant infections, which reproduce way faster than any macro-organism. We can see evolution of individual traits in some larger organisms, but still the time frame over which evolution of entire species happens is generally way beyond our lifetimes. It's not so much about how many offspring something has, but rather how fast a generation passes on average. And of course, what immediate evolutionary pressures are present.

People talk about evolution a lot, but I really don't think most people grasp the amount of time it takes for this to happen, w.r.t. the amount of time life has been around on Earth. Humans are generally very short-sighted.

Sorry Huey, that's not directed at you specifically. Just my observation about evolution in the mass media being taken to happen within one or two generations, or even one individual. That's simply not the case.

 

[Deleted member 133]

Not discrediting evolution at all, because I firmly believe in it, but I am surprised we haven't been able to witness it with our own eyes in species that propagate profusely. You would think in species like fish and insects that have large amounts of offspring, there should mutations that happen quite frequently. But then again, maybe we have seen it when they find a new species from time to time.

You raise a very good point.

When you say "we haven't been able to witness it" I assume you mean the likes of you and I, rather than those scientists who actually study it. For example here's the summary of the first paper that turned up in a Google search for "evolution in bacteria" that I just did. I chose bacteria (rather than fish and insects) because of the very short time between generations.

Long-term phenotypic evolution of bacteria

For many decades comparative analyses of protein sequences and structures have been used to investigate fundamental principles of molecular evolution. In contrast, relatively little is known about the long-term evolution of species’ phenotypic and genetic properties. This represents an important gap in our understanding of evolution, as exactly these proprieties play key roles in natural selection and adaptation to diverse environments. Here we perform a comparative analysis of bacterial growth and gene deletion phenotypes using hundreds of genome-scale metabolic models. Overall, bacterial phenotypic evolution can be described by a two-stage process with a rapid initial phenotypic diversification followed by a slow long-term exponential divergence. The observed average divergence trend, with approximately similar fractions of phenotypic properties changing per unit time, continues for billions of years. We experimentally confirm the predicted divergence trend using the phenotypic profiles of 40 diverse bacterial species across more than 60 growth conditions. Our analysis suggests that, at long evolutionary distances, gene essentiality is significantly more conserved than the ability to utilize different nutrients, while synthetic lethality is significantly less conserved. We also find that although a rapid phenotypic evolution is sometimes observed within the same species, a transition from high to low phenotypic similarity occurs primarily at the genus level.

Jeff

ps. I'm glad you are not trying to discredit evolution. Nobody has successfully done so to date.

ps. Whether you or I "believe" in it, firmly or otherwise, is irrelevant. Unlike religion (where all gods disappear as soon as everyone stops believing in them), evolution will continue even if and when there are no humans left on the planet. (Afterall evolution goes hand-in-hand with life on earth, and humans have existed for but the smallest fraction of time that life has existed here.)

 

[Deleted member 133]

Actually where we see it most is microbes, for example in antibiotic resistant infections, which reproduce way faster than any macro-organism. We can see evolution of individual traits in some larger organisms, but still the time frame over which evolution of entire species happens is generally way beyond our lifetimes. It's not so much about how many offspring something has, but rather how fast a generation passes on average. And of course, what immediate evolutionary pressures are present.

People talk about evolution a lot, but I really don't think most people grasp the amount of time it takes for this to happen, w.r.t. the amount of time life has been around on Earth. Humans are generally very short-sighted.

Sorry Huey, that's not directed at you specifically. Just my observation about evolution in the mass media being taken to happen within one or two generations, or even one individual. That's simply not the case.

You beat me to it Pauly!

Jeff

ps. I wonder however, if the example of drug resistant microbes is a good one. I at first was going to cite it in my reply, but on second thought withdrew it. Where a drug eliminates 99.99% of a microbe population, but leaves .01% intact, and that .01% goes on to reproduce, is there really "evolution" happening? Is this a new species that's created? I don't think so. I don't think the gene structure of the surviving microbes have changed at all. Could be wrong. What do you think?

Jeff

 

[PaulyT]

^--- For a micro-organism to pass on the ability to resist a particular antibiotic to future generations, I think yes, gene structure necessarily has to change. Whether this is evolution of an entire new species - defined by the ability of the organisms to reproduce with each other - is kind of a different question. Though with microbes, which don't necessarily reproduce sexually, I'm not sure how one clearly defines "species." I'm far from an expert in this area...

In other words, is there a difference between "adaptation" and "evolution"? I think the former is on a shorter time scale, by far, but the general mechanism is the same.

 

[Deleted member 133]

^--- For a micro-organism to pass on the ability to resist a particular antibiotic to future generations, I think yes, gene structure necessarily has to change. Whether this is evolution of an entire new species - defined by the ability of the organisms to reproduce with each other - is kind of a different question. Though with microbes, which don't necessarily reproduce sexually, I'm not sure how one clearly defines "species." I'm far from an expert in this area...

In other words, is there a difference between "adaptation" and "evolution"? I think the former is on a shorter time scale, by far, but the general mechanism is the same.

Good points.

Would we say the same in the case of "traditional" plant and animal breeding? Take dogs for example. All descended from wolves that were bred for certain characteristics by man, resulting in Chihuahuas and Great Danes!

Jeff

 

[Huey]

I hadn't even thought about bacteria or things similar, which would have an easier time with evolution just because of their sheer numbers. Although Paul's statement kind of goes against Jeff's underlined comment in the first post. If I read it right, evolution is not a reaction type of event, but more of a random mutation.

I'll throw this out, when I was in my weed class in college, no not that type of weed, my teacher made the statement that herbicide resistant weeds aren't created, but that they have always been here, and that we just selected for them in our continuous use of a single mode of action herbicide. Might this actually be what we are seeing in drug resistant bacteria and the like?

And yes, I do believe in evolution, and I recommend everyone go out right now and rent the movie Evolution! :happy-smileygiantred:

Oh yeah, and then I saw this article today. :text-link:

 

[PaulyT]

I think the artificial pressure of intentional selection of animal traits by humans, while broadly speaking uses the same mechanism (random changes in a generation are selected - by people instead of nature - for continuation to successive generations), is not the same as evolution primarily because it does not necessarily produce a species more fit for survival. In fact I think usually it's the opposite - pure-bred animals are widely known to have so many problems from in-breeding that without careful human attention, these "evolved" animals would die out pretty fast in the natural world.

As for the question of whether a Chihuahua is the same species as a Great Dane... honestly I don't know how modern taxonomy would classify the two. I've heard the term "sub-species" used, but I don't know if that's a scientifically precise term or just a general description. I do know that the old-school "kingdom-phylum-class-order-family-genus-species" stuff to describe the hierarchy of species that I learned in grade school is debunked these days, where more modern tools of genomic analysis have pretty much completely replaced that phenotypic method of classification.

 

[PaulyT]

Although Paul's statement kind of goes against Jeff's underlined comment in the first post. If I read it right, evolution is not a reaction type of event, but more of a random mutation.

No... The (good) point of Jeff's OP is that there are really *two* processes involved here. One is the random mutation of genes that produce (random) changes during reproduction. The other is some environmental pressure that would cause such a change to affect the survival of that individual. Random changes that increase survivability, in the long term, are collectively what is called "evolution." (In my words.)

In other words, evolution is not random. But the random mutation of gene sequences is what allows evolution to proceed.

Hope that makes sense...

 

[PaulyT]

See, this goes back to the comic I posted above, which was not entirely tongue-in-cheek, and which I thought was clever on the part of the author and apropos to this discussion. If a random mutation caused these animals to have mating calls like these, it is the reaction of their mates that provides the "environmental pressure" which lessens their ability to pass on their genes to offspring, because "no way am I going to mate with a male who spouts that kinda bullshit!" The mutation that causes that mating call may be random, in other words it happens without any intention or fore-knowledge of results; it's the environment that determines whether that mutation leads to a better chance of the individual passing on his genes to future generations.

 

[Deleted member 133]

Sorry, I stepped out for a swim, dinner and some beers. I'm back.

Agreed.

Jeff

 

[Huey]

Although Paul's statement kind of goes against Jeff's underlined comment in the first post. If I read it right, evolution is not a reaction type of event, but more of a random mutation.

No... The (good) point of Jeff's OP is that there are really *two* processes involved here. One is the random mutation of genes that produce (random) changes during reproduction. The other is some environmental pressure that would cause such a change to affect the survival of that individual. Random changes that increase survivability, in the long term, are collectively what is called "evolution." (In my words.)

In other words, evolution is not random. But the random mutation of gene sequences is what allows evolution to proceed.

Hope that makes sense...

I'm probably being a little too literal here, but I'm not sure if I would call it environmental pressure, as it is more of an adaptation by the organism to the environment. We now have the ability to alter genes, ie Roundup Resistant crops, couldn't this be called evolution? And yes, you bastages with phd's are slightly above my thinking scale, but I'll try to keep up. lol

 

[PaulyT]

I'm not sure if I would call it environmental pressure, as it is more of an adaptation by the organism to the environment.

Same thing, really... That is, something about the environment causes a trait in the organism to be beneficial or detrimental to its survival. "Adaptation" is simply the inheritance of a trait that is beneficial to survival. Of course, traits that are detrimental to survival get lost, as the organisms with that trait die out.

We now have the ability to alter genes, ie Roundup Resistant crops, couldn't this be called evolution?

It's precisely analogous to the issue of antibiotic-resistant microbes. And yes, I would call it evolution, though the "environmental pressure" here is artificial and man-made - e.g. roundup is now present and the organism is forced to adapt or die, though in this case the adaptation is also man-made. It's the same general mechanism as "natural" evolution, in my mind, but here the environmental pressure is extreme and immediate. That wouldn't occur in nature where environmental changes are much longer term - changes in weather patterns, influence of other organisms, etc.

In other words, man has the ability to affect evolution on a time scale that's very short compared to the Earth's lifetime. I guess maybe you could argue semantics and say that this is not really "evolution" - but again, I think the mechanism is the same, so let's call it the same thing. (There are probably scientists who would disagree with me on this point... this really isn't my field so I'm no expert.)