1. Comment #111867 by appaZ on January 15, 2008 at 10:40 pm

First..... much rejoicing........I will now read on !

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2. Comment #111871 by S'allokay on January 15, 2008 at 11:06 pm

I like Free...
Although if it's good I'll purchase the paperback. Loaning a book seems to give more credence to the contents than sending a file, somehow.

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3. Comment #111891 by BAEOZ on January 16, 2008 at 1:02 am

Unfortunately the academy got scared and put in a bit about how evolution and religion don't conflict. This is a lie. I understand why they do it. I just don't think lying is good in the long run. Why is it a lie? Because evolution has no purpose, no end. Humans are no more evolved than a barnacle or amoeba. And we're still evolving into who knows what? It contradicts any religious belief that posits man as the purpose of creation. They should say this someday......

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4. Comment #111897 by Quetzalcoatl on January 16, 2008 at 1:11 am

I'll read the brochure in more detail later, but I think it's very useful, and a good method of educating those who might not really understand what evolution is.

As for the religion qualifier, perhaps they should have mentioned "except where religion purports to make judgements about the natural world". But that isn't what the brochure was for, I suppose.

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5. Comment #111903 by Steve Zara on January 16, 2008 at 1:21 am

Humans are no more evolved than a barnacle or amoeba.

We obviously are. I think you may mean "fitter". We are much more complex that those organisms, and so more changed (evolved) from ancestral forms. However, the fact that we are all around in the world today means we are all equally "fit".

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6. Comment #111918 by CJ22 on January 16, 2008 at 2:27 am

We've evolved to be more complex. Quantifying how 'evolved' we are is a meaningless concept. But not all species are necessarily equally fit simply because they're still extant, since some might be in the process of 'failing'. You could argue that barnacles are more fit than humans, since they can exist almost anywhere there's salt water, and we need artificial support to live outside of all but the most human-benign environment.

Actually, making comparisons is a waste of time. It's like a race where we all started at different times, from different places, and everybody has there own finish line.

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7. Comment #112006 by Pilot22A on January 16, 2008 at 7:41 am

"about the inability of science to challenge all religious beliefs,"

So, again the idea rears it's ugly head that somehow science should explain all of religion's inconsistencies, why is that?

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8. Comment #112014 by Epinephrine on January 16, 2008 at 7:57 am

Steve Zara, re: humans being more evolved

We obviously are. I think you may mean "fitter". We are much more complex that those organisms, and so more changed (evolved) from ancestral forms. However, the fact that we are all around in the world today means we are all equally "fit".

I'm not sure I agree - I think by one definition amoebas are more evolved, in that they have had more generations over which they have changed (or had the opportunity to). The subject comes up again and again, I'm not sure that there is any right way of putting it. Clearly bacteria evolve faster than we do, they're continually changing.

I agree that one can't use the term "fitter", and I don't like the concept of "more evolved", the only way one can truly measure that is as a function of the number of selction events and the mutation rate (or some similar set of attributes). Invisible changes can take place, evolution of biochemical pathways and such, and they are as much evolution as morphological changes are. I'm sure you know this, but it's easy to use terms like "more evolved".

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9. Comment #112017 by Steve Zara on January 16, 2008 at 8:01 am

I'm not sure I agree - I think by one definition amoebas are more evolved, in that they have had more generations over which they have changed (or had the opportunity to). The subject comes up again and again, I'm not sure that there is any right way of putting it.

I agree it is difficult. But "more evolved" is probably technically correct. Evolution means "change", and we are more functionally changed from ancestral forms than amoebas.

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10. Comment #112018 by ianmkz on January 16, 2008 at 8:07 am

I agree it is difficult. But "more evolved" is probably technically correct.

I suggest that order to gain wider acceptance for evolution we introduce a term to convey this fuzzy sense of "more evolved":better. I think that might go down well with Huckabee and his kind; "I am better than a chimpanzee."

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11. Comment #112019 by irate_atheist on January 16, 2008 at 8:07 am

7. Comment #112006 by Pilot22A -

More like "the inability of scientists to be honest and challenge all religious belief."

Some like Dawkins and Pinker do, some others are fudgers, liars or deluded.

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12. Comment #112021 by Quetzalcoatl on January 16, 2008 at 8:11 am

Epinephrine-

I'm not sure I agree - I think by one definition amoebas are more evolved, in that they have had more generations over which they have changed (or had the opportunity to).

What about animals such as crocodiles and sharks, that have been around since the Mesozoic yet changed very little in that time?

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13. Comment #112022 by irate_atheist on January 16, 2008 at 8:11 am

10. Comment #112018 by ianmkz -

I think that might go down well with Huckabee and his kind; "I am better than a chimpanzee."

Are you seriously suggesting that Huckabee is better than a chimpanzee?

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14. Comment #112039 by Epinephrine on January 16, 2008 at 8:37 am

Quetzalcoatl -

What about animals such as crocodiles and sharks, that have been around since the Mesozoic yet changed very little in that time?

They haven't changed much morphologically, but we don't know to what extent they have changed in biochemical ways. Looking at the DNA for species that are thought not to have changed has been illuminating in this respect, showing us that species that we thought were the same are in fact quite different - I have no doubts that while a stable morphology has been found, molecular evolution has continued to act on crocodilians, sharks, coelacanths and other "living fossils", just as we see birds that are from outward examinations the same species but are genetically very different.

Edit - figured it would be studied, here's an example, here's an article on crocodile molecular evolution....

L. Rex McAliley, Ray E. Willis, David A. Ray, P. Scott White, Christopher A. Brochu and Llewellyn D. Densmore III, Are crocodiles really monophyletic?--Evidence for subdivisions from sequence and morphological data, Molecular Phylogenetics and EvolutionVolume 39, Issue 1, , April 2006, Pages 16-32.


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15. Comment #112043 by Quetzalcoatl on January 16, 2008 at 8:41 am

Good point, hadn't considered that.

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16. Comment #112053 by Steve Zara on January 16, 2008 at 8:56 am

I have no doubts that while a stable morphology has been found, molecular evolution has continued to act on crocodilians, sharks, coelacanths and other "living fossils"

It would be really very interesting if it had continued, but it would surely be only in very restricted ways, as the morphology of these creatures has probably not changed that much, and neither has the environment.

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17. Comment #112066 by _J_ on January 16, 2008 at 9:13 am

'no more evolved'

'more evolved'

'more complex'

'better'

For what it's worth, I really think that, for the purposes of general use, we should go with 'differently evolved'. Steve, I appreciate the distinction you're making when you talk about the degree of change and complexity (and your further point about molecular evolution, Epinephrine). And it makes sense to talk in such ways here.

But the phrase 'more evolved' will automatically come to carry the meaning 'better evolved', 'more highly involved', 'superior', 'what Creation was Created for' in the minds of people who are not familiar and comfortable with evolution, and who have significant religious leanings.

Some things change in some ways, other things change in other ways. Some have changed lots, some have changed less. All have spent the same amount of time being changed (or not changed) by their environments.

That's the thing we need everyone to swallow before we introduce distinctions that are liable to pull against it. I reckon.

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18. Comment #112072 by Steve Zara on January 16, 2008 at 9:21 am

But the phrase 'more evolved' will automatically come to carry the meaning 'better evolved', 'more highly involved', 'superior', 'what Creation was Created for' in the minds of people who are not familiar and comfortable with evolution, and who have significant religious leanings.

This is a very good point. I can see a difficulty in finding the right terms. Personally, I am reacting against a Gouldian tendency to assume that evolution really isn't directional. It clearly is, as the increase in variety of organisms over time leads inevitably to life exploring new realms of complexity. There are also features that seem pretty inevitable, such as increasing brain size and the development of eyes. I think some organisms really are superior to others, in the sense of being able to out-compete others and exploit wider ranges of environments.

Perhaps we need to not be so defensive, and reclaim ideas of "superiority"? Just thinking out loud here...

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19. Comment #112140 by annabanana on January 16, 2008 at 12:32 pm

No, no, superiority complexes are widespread as it is. No need to try and spread them any further. Not to mention, if who's to say that we are superior yet? If we continue on the way we have been and eventually squander all of our resources, eventually leading to our extinction, we couldn't be considered superior then. I suppose superiority is only relative anyway.

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20. Comment #112141 by Steve Zara on January 16, 2008 at 12:37 pm

No, no, superiority complexes are widespread as it is. No need to try and spread them any further.

Fair enough.

Not to mention, if who's to say that we are superior yet? If we continue on the way we have been and eventually squander all of our resources, eventually leading to our extinction, we couldn't be considered superior then. I suppose superiority is only relative anyway.

Yes. It is so hard to discuss these things without sounding like you are making value judgments. If, as I hope, we manage to colonise other planets and take Earth life there, then I think there is value to that. It would seem to me to be a little mean to argue otherwise (unless you are a nihilist atheist!).

I guess I am trying to argue that there is "more to" a human than an amoeba. But as the species Amoeba dubia has 200 times the DNA of humans in every cell, perhaps I should shut up!

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21. Comment #112151 by Peacebeuponme on January 16, 2008 at 1:14 pm

This conversation is kinda reminding me of the discussions about morality. We don't like to deal in absolutes of right and wrong there, and I don't think we need to in terms of better/worse or "more evolved" here.

I'm not really saying anything that hasn't been said above, but felt like chipping in. _J_ and anna seem to have the right idea to me.

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22. Comment #112155 by annabanana on January 16, 2008 at 1:23 pm

No nihilism here.

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23. Comment #112158 by Steve Zara on January 16, 2008 at 1:30 pm

This conversation is kinda reminding me of the discussions about morality. We don't like to deal in absolutes of right and wrong there, and I don't think we need to in terms of better/worse or "more evolved" here.

How would you describe a multi-cellular organism as against, say a bacteria? Or an animal that is a tool-maker as against an earthworm?

Mutation combined with selection does something. Some species are the result of stronger selection pressures than others. How do we describe the result of that stronger selection pressure?

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24. Comment #112163 by Peacebeuponme on January 16, 2008 at 1:38 pm

Steve

You have a point when you take it to extremes, but its still a case of "more" what, "better" at what. Your Amoeba example highlights that.

I'm just very uncomfortable with a hanging "better", especially since its what creationists do: we are better than other animals, it's an insult to say we came from them.

That's why I like _J_'s "differently evolved". There used to be rodents the size of cows, then selection pressure made them a lot smaller. How would you apply "more evolved" or "better" to that?

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25. Comment #112164 by annabanana on January 16, 2008 at 1:42 pm

How do we describe the result of that stronger selection pressure?

This is an interesting question to contemplate. It also brings up issues such as that there are pressure to stay the same as well as pressures to change. Although, I suppose you could look at pressure to stay the same as non-pressure. It also depends on how specialized an organism is. If an organism has evolved to be particularly specialized to live in a certain environment such as some of the "worms" found around the hot vents in the oceans, then it will benefit the organism not to change very much. Maybe it's tied to mobility. At the present (without having done any sort of research, just thinking) it seems that the more mobile the organism, the more pressures there are to be able to adapt to different environments and develop a number of survival mechanisms.

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26. Comment #112166 by Steve Zara on January 16, 2008 at 1:44 pm

I'm just very uncomfortable with a hanging "better", especially since its what creationists do: we are better than other animals, it's an insult to say we came from them.

Yeah, I understand where you are coming from.

That's why I like _J_'s "differently evolved". There used to be rodents the size of cows, then selection pressure made them a lot smaller. How would you apply "more evolved" or "better" to that?

To me, "differently evolved" implies (perhaps wrongly) the same amount of evolution, but in different directions. I forget what it is called, but there is a certain species of mollusc that seems to have lived the same lifestyle in a muddy bay for millions of years. Just because the same amount of time has passed, does not mean it has experienced the same "amount" of evolution as other species. I can't easily fit the "reduced size rodent" into any way of categorising things, but I still feel there could be some measure of having "evolved a lot". Some combination of genetic and physical complexity.

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27. Comment #112169 by Steve Zara on January 16, 2008 at 1:47 pm

it seems that the more mobile the organism, the more pressures there are to be able to adapt to different environments and develop a number of survival mechanisms.

Generally, yes, I think that is useful. However there is an interesting counterexample, which is corals. They aren't that mobile, but battle each other for space, and are in a constant arms race.

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28. Comment #112172 by annabanana on January 16, 2008 at 1:52 pm

This is true, I was just watching the Blue Planet about it the other night...do we have a good record of how much they have evolved?

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29. Comment #112176 by Steve Zara on January 16, 2008 at 1:55 pm

do we have a good record of how much they have evolved?

I have no idea! That is an interesting question.

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30. Comment #112177 by Peacebeuponme on January 16, 2008 at 1:56 pm

To me, "differently evolved" implies (perhaps wrongly) the same amount of evolution, but in different directions.

Interesting discussion, this. Anytime you are dealing with terminology, there's a can of worms.

I still feel there could be some measure of having "evolved a lot". Some combination of genetic and physical complexity.

Yes, and I understand why you'd want that. Talking about amount or rate of change over time is not the same as placing on a chart of higher to lower organisms. Though would be hard to apply where an organism had been through stages of increasing and decreasing physical complexity, or gaining and losing stretches of DNA code.

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31. Comment #112180 by Steve Zara on January 16, 2008 at 1:59 pm

Yes, and I understand why you'd want that. Talking about amount or rate of change over time is not the same as placing on a chart of higher to lower organisms.

I agree.

Though would be hard to apply where an organism had been through stages of increasing and decreasing physical complexity, or gaining and losing stretches of DNA code.

Yes, or when there has been a substantial descrease in the complexity of the adult phenotype, as with the sea squirt, which evolved from something with a reasonable nervous system.

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32. Comment #112182 by Peacebeuponme on January 16, 2008 at 2:05 pm

Steve

I said "decreasing phsysical complexity". You said "Decrease in the complexity of the adult phenotype". I feel like I'm about to ask a thickie question, but aren't they the same thing?

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33. Comment #112183 by Steve Zara on January 16, 2008 at 2:06 pm

I said "decreasing phsysical complexity". You said "Decrease in the complexity of the adult phenotype". I feel like I'm about to ask a thickie question, but aren't they the same thing?

Er, yes. Sorry. I should read more slowly. I just think that sea squirts are wonderfully odd in this respect.

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34. Comment #112185 by Epinephrine on January 16, 2008 at 2:09 pm

It almost sounds like the idea of specialisation is being confused with the idea of evolution and evolvedness. (Did I make up a word?)

Certainly the most obvious cases for evolution are often extreme specialisations; a peacock's extravagant tail as a specialised sexual signal, the 18 visual pigments of the mantis shrimp, or the mutual fig and fig-wasp specilisation. It would certainly seem that specialisation requires evolution, but diversification doesn't always result when evolution takes hold.

Coelacanths originally had many species and body types, but only one variety (I think) has survived to the present - is this reduction of diversity of the coelacanth an evolution, even though the one type that remains is largely morphologically unchanged?

Maybe rather than trying to refer to evolution in terms of quantifying it (more evolved/less evolved) which in my mind revolves around mutation rates, number of selection events, etc., and is possibly unmeasurable due to invisble evolution (molecular evolution), we could used terms like specialised, adapted, differentiated, generalised, generic or some such.

Thus a fig wasp is highly specialised and specific, whereas other creatures may be less specific and more generalist or opportunistic species are less specialised and inhabit broader ranges, often showing less change over time? Just trying to think through this...

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35. Comment #112188 by mesomodel on January 16, 2008 at 2:20 pm

I don't see the problem of comparing organism A with organism B and asking which is more evolved. Just trace back to the common evolutionary ancestor of A and B and then determine whether A or B is genetically closer to the common ancestor. That which is closer is less evolved. Such a comparison says nothing about which is more superior, however.

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36. Comment #112189 by Peacebeuponme on January 16, 2008 at 2:22 pm

Maybe rather than trying to refer to evolution in terms of quantifying it (more evolved/less evolved) which in my mind revolves around mutation rates, number of selection events, etc., and is possibly unmeasurable due to invisble evolution (molecular evolution), we could used terms like specialised, adapted, differentiated, generalised, generic or some such.

I'm not sure how well that would aid comparison, apart from between similar species, and even then it would be hard. To take your example: is the fig wasp the best at being a wasp, or is it the spider wasp?

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37. Comment #112193 by Geoff on January 16, 2008 at 2:26 pm

The way I see it, the only way to use "better evolved" would be in the sense of "fitter in its particular environment".

That then implies that a "worse evolved" organism (in the same environment) is on the way to extinction as a result of competition.

"More evolved" is trickier, and I'd propose that one would have to look at the number of functional (i.e. those with a phenotypic effect) changes in the DNA (compared to a common ancestor).

Or is that too simplistic? I'm no biologist.

Edit: mesomodel kinda beat me to it there!

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38. Comment #112198 by Geoff on January 16, 2008 at 2:45 pm

Steve said:

Some species are the result of stronger selection pressures than others. How do we describe the result of that stronger selection pressure?

True, but I can't help considering other species as being part of that pressure. We could say, for example, that a cheetah is "more evolved" than its cat ancestor, but "better evolved"? Probably not, since they're said to be on the verge of extinction. In a very real sense, they've lost their "arms race".

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39. Comment #112200 by Steve Zara on January 16, 2008 at 2:47 pm

True, but I can't help considering other species as being part of that pressure.

Certainly.

We could say, for example, that a cheetah is "more evolved" than its cat ancestor, but "better evolved"? Probably not, since they're said to be on the verge of extinction. In a very real sense, they've lost their "arms race".

I agree. I don't think "more evolved" has any particular sense of being "better".

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40. Comment #112201 by Goldy on January 16, 2008 at 2:54 pm

More evolved

Odd term. How can anything be more evolved? man is apparently more evolved than a shark - well, yes, man is...on land. Absolutely stuffed in the water. Never mind not being more evolved in the sea, man is also way less fit :-)
Everything is as evolved as each other, as I see it. Some have not developed any more because, well, they weren't broke so needed no fixing. That's not to say they haven't changed any - aparently archaic H. sapiens isn't that much more evovled than we are now - but we are not the same. We aren't even the same as our fairly recent ancestors.
I remember reading about how peopple are growing shorter in Brazil as a function of their poverty (obviously only a subset of the population). Can you say they are better evolved? After all, they're not exactly fitting the definition of better, are they? But they are evolving to their circumstances, their environment, so yes, they are better evolved. Less energy needed so less resources used in their growth. They are more evolved because they show changes more than we do (I think). Their DNA would be pretty identical to ours too...

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41. Comment #112202 by BAEOZ on January 16, 2008 at 2:55 pm

Wow I kicked off quite a little discussion in terminology. So where are we? Do we reject more evolved? I think I should have said that humans and amoeba were equally fit. Anyway, I don't think evolution is teleological, it has directions, but the directions aren't meeting an end. That was my point. Scientists who don't dispute believers' concept of evolution as being the means to God's end are doing science a disservice IMO.

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42. Comment #112203 by Epinephrine on January 16, 2008 at 2:58 pm

Measuring genetic difference from most recent common ancestor makes sense in terms of quantifying evolution - that's about the only type of "more evolved" I can picture.

As to which is a "better" wasp, I don't think one can answer that kind of question - I was just pointing out that a fig wasp might be thought of as more specialised than a yellowjacket. Comparing it to another very specialised wasp on the other hand is tricky - I'm not sure how one could define specialisation though.

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43. Comment #112204 by Steve Zara on January 16, 2008 at 2:59 pm

Odd term. How can anything be more evolved? man is apparently more evolved than a shark - well, yes, man is...on land. Absolutely stuffed in the water. Never mind not being more evolved in the sea, man is also way less fit :-)

To evolve is to change. Some organisms demonstrate more change from ancestral forms than others.

Anyway, I don't think evolution is teleological, it has directions, but the directions aren't meeting an end. That was my point.

Yes, I think this is the key issue.

Everything is as evolved as each other, as I see it. Some have not developed any more because, well, they weren't broke so needed no fixing.

But surely then, by definition, they are less evolved, as they have not changed as much.

I think the question is how one can put a measure on the amount of evolution, not that species differ in that amount. My current view is that some measure of phenotypic complexity would be appropriate.

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44. Comment #112206 by Goldy on January 16, 2008 at 3:03 pm

The only way I can see something being more evolved is if it has a shorter lifespan. I am more evolved that a bristlecone pine and less evolved than a fruitfly as a function of our relative lifespans :-) (as mentioned above)
You'd have to measure the genetic difference from the original source, mind...no easy matter. We are different from Neanderthal and they were once genetically very similar when we shared a H. erectus ancestor. Same with the great apes. I dare say all are as genetically different to the ancestor as each other.

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45. Comment #112207 by Goldy on January 16, 2008 at 3:08 pm

Steve, I know they are less evolved by comparing their physical bodies, but they are still subject to the evolutionary forces. They are not changed physically, but in other ways? Can H. sapiens mate and produce viable offspring with H. neanderthalis? There is, I know, very slight evidence that it did happen, but not 100%, as far as I can gather. yet the differences were not really that great.
edit - I used the word "developed" above - I should have used the word "changed"

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46. Comment #112208 by Steve Zara on January 16, 2008 at 3:09 pm

Steve, I know they are less evolved by comparing their physical bodies, but they are still subject to the evolutionary forces.

Evolutionary forces can vary in strength and direction. A sudden change in environment can result in considerable change in one organism, and perhaps not so much in others.

The only way I can see something being more evolved is if it has a shorter lifespan.

You can also get "more evolved" if there is greater selection pressure during a lifetime, something that culls more of a population. Of course, having a shorter lifespan will help, as it allows more variation to be selected during a given time period, but it is not a requirement to provide variability in a short time. Yet another possibility is having a vast number of offspring.

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47. Comment #112210 by Goldy on January 16, 2008 at 3:11 pm

Steve, I know, but having a greater number of generations makes these changes more apparent. The offspring, while different from the parents, are not evolved to an extent as to make them genetically different.
Edit. I am European, my wife Chinese, our daughter Eurasian. Different, but genetically so similar. Be quite a few generations before we can say there has been some serious evolution going on ;-)

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48. Comment #112211 by Steve Zara on January 16, 2008 at 3:13 pm

The offspring, while different from the parents, are not evolved to an extent as to make them genetically different.

Well, there will always be some genetic difference, from both mutations and from the shuffling of genes that comes from sexual reproduction. And having a very large number of offspring means that there will be an increased count of offspring with mutations of various kinds.

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49. Comment #112212 by ianmkz on January 16, 2008 at 3:16 pm

Can we say that a "more evolved" form is one which has suffered greater gene attrition?

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50. Comment #112213 by Goldy on January 16, 2008 at 3:19 pm

Yes, Steve, but not so much as to make them a new species or even a subspecies. They are still near as dammit identical to their parents. I know you can say they are evolved, but more evolved? Or less? Or even significantly evolved?

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