Is macroevolution impossible to study?

| 49 Comments

Once again, the Discovery Institute is playing word games with educational systems, trying to give legal protection to religion-based incompetence. I refer, of course, to the ongoing debate about standards in Texas, and the insidious influence that the DI is wielding.

As Wesley Elsberry notes in his summary of the alleged weaknesses of evolutionary theory, an oft-repeated mantra rears its head yet again. This ID tenet holds that macroevolution is either not possible, or cannot be observed, or cannot be studied (or any combination of the these). Apparently, Board of Education member Ken Mercer is of the opinion that macroevolution has not been observed.

This is one of the “weaknesses” that really betrays the many levels of ignorance of the ID proponent. For it implies that, because it would seem to be impossible to replicate a complete macroevolutionary transition that is expected to take millions of years, it is not possible to test specific questions about the process using the time-honored process of hypothesize, test using controlled and repeatable experiment, and revise. This is patently ludicrous.

Worse still, however, this ID claim implies that macroevolution cannot be observed in controlled experimental settings. As the following discusses, this is false. (Of course, I must add a caveat here. When cornered, the ID proponent will define macroevolution as any evolution that has not been observed. Of course, this deflates their objections, or should if one cares a whit about the irrelevance of circular reasoning, but logical consistency isn’t something we expect from the Discovery Institute.)

To begin with, it helps to reflect on what might constitute a macroevolutionary transition. Ask yourself, if you might, what distinguishes, say, animals from plants. Curious and perceptive students could come up with an interesting list, and I daresay many of the distinguishing characteristics would trace themselves to a fundamental difference that is seen at the cellular level. Of course, this difference is the presence of an organelle - the chloroplast - in plant cells that is absent from animal cells. This difference distinguishes entire kingdoms, and changes that modified an organism such that it possesses a new, additional, organelle would undeniably be considered as macroevolutionary. Similarly, changes that are clearly in such a pathway would have to be considered macroevolutionary.

Enter into the picture the long-running studies of Kwang W. Jeon. More than 40 years ago, Jeon and Lorch reported the discovery of a novel strain of Amoeba proteus, so-called xD amoeba (2). This strain differed from its parent (the D strain) in that it possessed a bacteria-like endosymbiont (termed XB, and shown later to be related to Legionella species). xD amoeba are totally dependent on their endosymbiont, as removal of the XB bacteria from the xD strain is lethal to the amoeba. xD amoeba possess a number of novel proteins; one of these interferes with lysosomal recognition of the endosymbiont, one (a nuclear protein) inhibits growth of D amoeba, and one (coded for by the so-called s29x gene) is encoded by the XB genome and exported to the cytoplasm. (This is likely far from an exhaustive list of novel proteins found in xD amoeba - I am not aware of proteomic studies that have been conducted with xD amoeba.) More recent studies have shown that the XB endosymbiont directly controls the expression of at least one nuclear gene, possibly via adenine methylation. (This modification is typically found in prokaryotes, and its occurrence in the xD strain suggests that the XB Dam methylation system can access the nucleus of the xD strain, perhaps by the same mechanisms that allow the s29x protein to pass from endosymbiont to cytoplasm.)

Reflect, now, on the ramifications of this system. Organelles such as the chloroplast and mitochondria arose by endosymbiotic events. What we see with xD amoeba are the early stages of another such event. The xD strain is dependent on the endosymbiont, much as plant cells depend on chloroplasts, and eukaryotic cells on mitochondria. Moreover, as is the case with more recognizable organelles, gene expression and cellular physiology in the xD strain have become interdependent, such that endosymbiont and nucleus communicate and control expression and metabolism. This system is arguably the beginnings of the evolution of a new organelle, something that would be tantamount to the origination of a new kingdom.* By any reasonable measure, what Jeon and his coworkers have been studying is an example of macroevolution. His system stands out as a refutation (NOT the only one, but merely one interesting example of what are likely many) of this oft-repeated (and erroneous) ID claim, that macroevolution has not been, and cannot be, observed or studied.

A recent review that can be used to follow the history of this fascinating system:

1. Jeon, K. W. 2004. Genetic and physiological interactions in the amoeba-bacteria symbiosis. J Eukaryot Microbiol 51:502-8.

A few other selected references:

2. Jeon, K. W., and I. J. Lorch. 1967. Unusual intra-cellular bacterial infection in large, free-living amoebae. Exp Cell Res 48:236-40. 3. Jeon, T. J. 2008. DNA adenine methylation of sams1 gene in symbiont-bearing Amoeba proteus. J Microbiol 46:564-70. 4. Jeon, T. J., and K. W. Jeon. 2004. Gene switching in Amoeba proteus caused by endosymbiotic bacteria. J Cell Sci 117:535-43. 5. Lorch, I. J., and K. W. Jeon. 1981. Rapid induction of cellular strain specificity by newly acquired cytoplasmic components in amoebas. Science 211:949-51. 6. Pak, J. W., and K. W. Jeon. 1997. A symbiont-produced protein and bacterial symbiosis in Amoeba proteus. J Eukaryot Microbiol 44:614-9.

* - what seems to be missing from the xD amoeba are examples of bacteria genes that have picked up and moved into the nucleus. Such examples may remain to be discovered, or it may be too early in the evolution of the system to expect such events. Regardless, if and when the pertinent experiments are done, they can be expected to shed interesting insight into the movement of DNA between compartments in other systems.

Postscript - I would appreciate any pointers to studies of this system that have been authored by other groups, or papers that do not appear in Pubmed or Google Scholar. These may be left in the comments, either on The Panda’s Thumb or here.

49 Comments

But you’re dind’t saw it happen! Godmustadidit! HAH! pwned!

(poe)

The evidence for the endosymbiotic origin of both mitochondria and chloroplasts is so convincing that only someone who was totally ignorant of the evidence would ever claim that macroevolution is impossible, or cannot be studied, or can not be observed, or any combination of these.

Once again, a well informed public is the best defense against such ingorant nonsense. Hopefuly enough people still value education and science that, in the words of Lisa Simpson, we won’t let the butt heads win.

Does anyone know why the endosymbiont is necessary to the amoeba?

The endosymbionts will be seen as macro evolution by scientists and the learned. But the creotards are not interested in understanding any term nor are they stumped by ny logical inconsistency. Because what it is described involves “microbes”, the demagogues will simply say “Ye, faithful! Lo! What these dumb materialistic Darwinists are saying. Some evolution happening in microscopic bugs and is touted as an example of macroevolution! Darwinism is clutching at straws. Rejoice! It is in its last legs. Please donate generously to help me fight and defeat these evilutionists and bring the Kingdom of God on Earth! Hallelujah!”

I would suggest we talk more about the “Ring species”. It is essentially macro evolution happening and going on right now, and we are witnessing it. The salamanders in that California lake, two species of gulls around the north pole, the green warbler species around the Himalayas excellent examples.

It is impossible to convince the creotards. But the genuinely moderate people who are not knowledgeable enough to be aware of endosymbionts and eukaryotic enslavement of the downtrodden underclass of mitochondrians etc are more likely to understand and appreciate the “Ring species” better.

Of course non-biologists like me who love the logical explanations provided by the biologists explaining the diversity of life, typical readers of Dawkins, Dennet, Ghould and Shubin books, will take the trouble to understand the argument and express admiration for the work. But to get past the propaganda of the Deception Institute, a series of six stuffed dolls of Herring Gull transitioning to lesser black backed gull marketed to children is a better idea.

Macroevolution HAS been observed, and can be observed today by anyone with an unbiased, open mind. The entire Fossil Record IS the Fact of Evolution, that crys out for an explanation. The best explanation is the Theory of Evolution by descent with modification through natural selection.

We DO observe evolution in progress, for millions of years into the past (thanks to Physics we know the time span). We have a time machine, and it is called Stratigraphy. It does not depend upon radionuclide dating techniques. It depends only upon Steno’s observation (law) that younger beds are deposited upon older beds. (Some, if not many, creationists deny this - they have to or their entire belief system falls apart.)

Happily, we have the entire science of Physics to give us temporal bounds on the layers in our world’s Stratigraphy. (All of the sciences of Stratigraphy, Paleontology, and all of Physics, have to be wrong for Creationism to be correct.)

Each and every fossil, in every museum cabinet and in-place in all the sedimentary rocks of the whole world, constitute the FACT of Evolution which the THEORY of Evolution seeks to explain.

It is correct to say that there are countless more examples of obligate endosymbioses. Perhaps the most remarkable is Paulinella chromatophora, another amoeba which appears to be on its way to acquiring a chloroplast. It is always found with two cyanobacteria inside its cells, and cannot live without them; furthermore, its closest relative eats only cyanobacteria. On the mitochondrial side, there is a whole “spectrum of mitochondriality” from the highly bacterial-like Reclinomonas through plant and animal mitochondria, various types of anaerobic mitochondria, hydrogenosomes, mitosomes, and finally tiny double-membrane-bound organelles that may or may not be the relics of the mitochondrial endosymbiont but are so reduced as to be hard to prove as such. Each of these carry out their own biochemical processes, and each shares relatively little genetically with all the others, but there is always some clue to their relatedness that renders any other hypothesis extraordinarily improbable.

I must take issue with the assertion that the evolution of a new endosymbiotically based organelle “would be tantamount to the origination of a new kingdom”. Kingdoms are a taxonomic construct, and so should be defined phylogenetically. To place a single strain of a single species in its own kingdom implies that all of its sister strains are similarly worthy of kingdom status, something that I doubt would be a worthwhile construct. Eukaryotic cells, meanwhile, vary tremendously within kingdoms, and the acquisition of a novel endosymbiont in a single strain of a single species is not so remarkable as to warrant that level of distinction, any more than the acquisition of language makes humans no longer animals.

Dear John,

Thanks for these and the rest of your excellent comments:

John Vanko said:

Macroevolution HAS been observed, and can be observed today by anyone with an unbiased, open mind. The entire Fossil Record IS the Fact of Evolution, that crys out for an explanation. The best explanation is the Theory of Evolution by descent with modification through natural selection.

Each and every fossil, in every museum cabinet and in-place in all the sedimentary rocks of the whole world, constitute the FACT of Evolution which the THEORY of Evolution seeks to explain.

What is most remarkable about the fossil record, especially of marine invertebrates, is that one can investigate both the collapse and recovery of marine ecosystems during mass extinctions, not just once, but at least seven or eight times in the past 600 million years of earth history. These are merely just a few of the many examples which show how macroevolution is occurring (Unless of course you’re some kind of creationist - ID or otherwise - who still subscribes to the illusion of a “Cambrian Explosion”, etc.).

Appreciatively yours,

John

One little quibble: the Fossil Record constitutes A fact of Evolution, as we have seen, as well as continue to see Evolution occurring, in the wild, like with the speciation events of the apple maggot fly in response to American agriculture, or cichlids repopulating Lake Victoria

, or in documentation of new plant and animal breeds, like with new orchid hybrids or designer cat and dog breeds. John Vanko said:

Each and every fossil, in every museum cabinet and in-place in all the sedimentary rocks of the whole world, constitute the FACT of Evolution which the THEORY of Evolution seeks to explain.

John Kwok said:

What is most remarkable about the fossil record, especially of marine invertebrates, is that one can investigate both the collapse and recovery of marine ecosystems during mass extinctions, not just once, but at least seven or eight times in the past 600 million years of earth history.

The very first reef-building animals were the Archaeocyathans who first appeared near the start of the Cambrian, just prior to the “Cambrian Explosion.” The colonial species accumulated mounds of themselves, termed, “bio-herms,” and were eventually ecologically displaced by the possibly related Demosponges in the beginning of the Middle Cambrian. Only one archaeocyathan was left by the close of the Cambrian.

During the Jurassic period, glass sponges underwent an evolutionary renaissance, building huge reefs. Then these reefs disappeared, or rather, their builders suddenly went kaput. Apparently, recent studies strongly suggest that these reef-building glass sponges died out, leaving only their slow-growing, deepwater cousins, was because the reef-building glass sponges consumed all of the available silica in the water at the time.

tresmal said:

Does anyone know why the endosymbiont is necessary to the amoeba?

The bacterium shtus down one of the amoeba’s copies of the sams1 gene thus making the host now dependent on the bacterial symbiont. Like an unhappy marriage it may be that host doesn’t really want its partner but it cannot live without it.

Neat stuff.

Species name should probably be “Amoeba proteus,” not “Ameoba proteus,” I think.…

Ah, that reminds me of Carl Zimmer’s posts Going Green and The Further Adventures of the Emerald Green Sea Slug, about the plantlikeness of Elysia chlorotica:

Recently, some scientists discovered that the sea slug is even more plantlike than previously thought thought. They wondered if some genes from the algae the slug ate had become incorporated into their own DNA. […] So Rumpho’s group gathered up some sea slugs off the coast of Martha’s Vineyard and took a look at their DNA. They also took a look at the DNA of the one species of algae that the slugs put in their skin. As they suspected, the plasmids don’t have all the genes necessary for photosynthesis. The scientists discovered a crucial photosynthesis gene, called psbO, in the DNA of the slug. In fact, the sequence of the slug’s psbO gene is identical to the one in the species of algae that supplies them with their plastids.

I wondered how in the world a gene from algae got into the slug’s own DNA. Rumpho responded (my notes in brackets):

Our thoughts are that the nuclei break open as they go through the guy, releasing their DNA. The DNA is then phagocytosed [eaten] along with the chloroplasts into cells lining the digestive system. The digestive system expands throughout the growing sea slug and interestingly it is found to branch right next to the reproductive organs. In addition, the invertebrate has an open “blood” system, so if the DNA was exchanged from the gut into the blood, it also would come in direct contact with the reproductive organs.

We are doing high-throughput sequencing now on the sea slug transcriptome [the genes expressed in specific cells] and hopefully soon, the genome, so we should learn a lot more about which genes are there. I will also mention that we frequently/always? find a virus in the sea slug that really takes off as the sea slugs age. We believe it might be a retro-virus, but the support is not strong at this time. It’s possible the DNA is moving via a viral vector through the blood to the germ line.

And I concur with Zimmer’s suggestion to visit Rumpho’s web site about this symbiosis - it is a feast for eye and mind:

In summary: the acquisition, incorporation and retention of intact algal plastids by E. chlorotica may be aided by the robustness of the V. litorea plastids. However, long-term functional activity of the plastids appears to be supported by both protein stability and contributions from the sea slug itself.

Hi Greg,

I fixed the typo. Thanks for catching it.

Art

The bacterium shuts down one of the amoeba’s copies of the sams1 gene thus making the host now dependent on the bacterial symbiont. Like an unhappy marriage it may be that host doesn’t really want its partner but it cannot live without it.

That sounds like the bacteria species had developed a defense against getting eaten - producing something that kills the amoeba. But at some point, an attempted ingestion didn’t complete, and the bacteria got stuck in there, accidentally (from its POV, anyway) keeping the amoeba alive.

It looks likely that it also means that the “infected” amoebas are now immune to that particular defense of the bacteria, so that they’re now free to munch on the relatives of their symbiont without fear of that particular defense mechanism?

Henry

Opisthokont said:

It is correct to say that there are countless more examples of obligate endosymbioses. Perhaps the most remarkable is Paulinella chromatophora, another amoeba which appears to be on its way to acquiring a chloroplast. It is always found with two cyanobacteria inside its cells, and cannot live without them; furthermore, its closest relative eats only cyanobacteria. On the mitochondrial side, there is a whole “spectrum of mitochondriality” from the highly bacterial-like Reclinomonas through plant and animal mitochondria, various types of anaerobic mitochondria, hydrogenosomes, mitosomes, and finally tiny double-membrane-bound organelles that may or may not be the relics of the mitochondrial endosymbiont but are so reduced as to be hard to prove as such. Each of these carry out their own biochemical processes, and each shares relatively little genetically with all the others, but there is always some clue to their relatedness that renders any other hypothesis extraordinarily improbable.

I must take issue with the assertion that the evolution of a new endosymbiotically based organelle “would be tantamount to the origination of a new kingdom”. Kingdoms are a taxonomic construct, and so should be defined phylogenetically. To place a single strain of a single species in its own kingdom implies that all of its sister strains are similarly worthy of kingdom status, something that I doubt would be a worthwhile construct. Eukaryotic cells, meanwhile, vary tremendously within kingdoms, and the acquisition of a novel endosymbiont in a single strain of a single species is not so remarkable as to warrant that level of distinction, any more than the acquisition of language makes humans no longer animals.

Thanks for that, for much the same reasons as you I was going to come in and say the same thing. I would also point out that with this Amoeba proteus it may only be a transitory endosymbiosis as well, and we have good reason to suspect that these may happen more frequently than we used to think. The endosymbiont may or may not become an organelle eventually but either way we gain useful knowledge by studying the system because it still gives us insight into endosymbiotic events and early organelle origins and evolution. And you are quite right on the kingdom thing, after all we would hardly place all of the protists that contain secondary and tertiary plastids into their own kingdoms.

Something else crying out for an explanation is the appearance of different clades of mammals on the different continents. There is a wonderful (and downloadable) pdf file at the BBC which clearly shows these relationships:

http://news.bbc.co.uk/2/hi/science/[…]/6503045.stm

If this link doesn’t work, try:

http://tinyurl.com/67tn4m

An especially nice touch is the “you are here” label.

I would suppose that a creationist could never convict someone of a crime based soley on the evidence collected, no matter how compeling, if no one had actually “observed” the crime being commited.

Dear Matt G -

You’ve merely touched the tip of the proverbial iceberg here:

Matt G said:

Something else crying out for an explanation is the appearance of different clades of mammals on the different continents. There is a wonderful (and downloadable) pdf file at the BBC which clearly shows these relationships:

http://news.bbc.co.uk/2/hi/science/[…]/6503045.stm

If this link doesn’t work, try:

http://tinyurl.com/67tn4m

An especially nice touch is the “you are here” label.

There’s a lot in the well documented history of life on Planet Earth which IDiots and other creationists would regard as “mysterious” as the so-called “Cambrian Explosion”, but instead, all of the major details of this history can be explained well by our excellent understanding as to how the interactions of plate tectonics, climatology and interspecific competition have promoted speciation on land, sea and air, during the approximately past 600 million years of the Phanerozoic Eon.

Regards,

John

Is “macroevolution” impossible to study? Yes, because the word “macroevolution” is a word with no meaning at all! “Macroevolution” means nothing but whatever strawman the current creationist needs to throw out to hide from the evidence. They just claim that “macroevolution” has never been observed (usually without even pretending to define the term in a meaningful way), and pretend this is some kind of deathblow to science. They can’t offer a speck of evidence that establishes any barrier between “microevolution” and “macroevolution”, they don’t bother to clearly define where they claim this barrier is, and they’ll move the goalposts on an instant’s notice. Any observed instance of “macroevolution” and they change the meaning of the word. “Macroevolution,” as used by creationists, is nothing more than a pointer to an ever-shifting pile of strawmen that exist only in their hollow heads. It is a term without anything resembling meaning.

Dear phantomreader42 -

Wait a second here:

phantomreader42 said:

Is “macroevolution” impossible to study? Yes, because the word “macroevolution” is a word with no meaning at all! “Macroevolution” means nothing but whatever strawman the current creationist needs to throw out to hide from the evidence. They just claim that “macroevolution” has never been observed (usually without even pretending to define the term in a meaningful way), and pretend this is some kind of deathblow to science. They can’t offer a speck of evidence that establishes any barrier between “microevolution” and “macroevolution”, they don’t bother to clearly define where they claim this barrier is, and they’ll move the goalposts on an instant’s notice. Any observed instance of “macroevolution” and they change the meaning of the word. “Macroevolution,” as used by creationists, is nothing more than a pointer to an ever-shifting pile of strawmen that exist only in their hollow heads. It is a term without anything resembling meaning.

Macroevolution is a scientifically acceptable term that is amply cited in the scientific literature on evolutionary biology; it has been cited for more than a century. More importantly, the best evidence for macroevolution is found in the fossil record of multicellular life, especially during the Phanerozoic Eon (which includes now and approximately the last 600 million years of Earth’s biological history).

Respectfully yours,

John

When used by creationists, “macroevolution” is, and always has been, an utterly meaningless, ever-shifting, deliberately underfinable term. Any scientific meaning has no relevance to these nutcases. Give the word a definition, and it can be observed, and has been, but that fact just sends the creationists into ever-deeper denial.

John Kwok said:

Dear phantomreader42 -

Wait a second here:

phantomreader42 said:

Is “macroevolution” impossible to study? Yes, because the word “macroevolution” is a word with no meaning at all! “Macroevolution” means nothing but whatever strawman the current creationist needs to throw out to hide from the evidence. They just claim that “macroevolution” has never been observed (usually without even pretending to define the term in a meaningful way), and pretend this is some kind of deathblow to science. They can’t offer a speck of evidence that establishes any barrier between “microevolution” and “macroevolution”, they don’t bother to clearly define where they claim this barrier is, and they’ll move the goalposts on an instant’s notice. Any observed instance of “macroevolution” and they change the meaning of the word. “Macroevolution,” as used by creationists, is nothing more than a pointer to an ever-shifting pile of strawmen that exist only in their hollow heads. It is a term without anything resembling meaning.

Macroevolution is a scientifically acceptable term that is amply cited in the scientific literature on evolutionary biology; it has been cited for more than a century. More importantly, the best evidence for macroevolution is found in the fossil record of multicellular life, especially during the Phanerozoic Eon (which includes now and approximately the last 600 million years of Earth’s biological history).

Respectfully yours,

John

Dear phantomreader42,

I don’t disagree with your assessment of the term “macroevolution” as used by creationists:

“When used by creationists, ‘macroevolution’ is, and always has been, an utterly meaningless, ever-shifting, deliberately underfinable term. Any scientific meaning has no relevance to these nutcases. Give the word a definition, and it can be observed, and has been, but that fact just sends the creationists into ever-deeper denial.”

However whenever you do refer to it as “meaningless”, PLEASE EMPHASIZE too that it is a scientifically meaningful term when used by paleobiologists and other evolutionary biologists interested in studying these phenomena as seen from the history of life on Planet Earth.

John

Heck with macroevolution, microevolution has never even been validated. Never once has science pinned down a random genetic change that has been proliferated by natural selection. I’m here if anyone would like to present evidence to the contrary.

I would like someone to present evidence for Micro-evolution.…this must include a random mutation that gets proliferated by natural selection. Thank you.

fly said:

I would like someone to present evidence for Micro-evolution.…this must include a random mutation that gets proliferated by natural selection. Thank you.

There’s too much evidence to present briefly. I recommend these two books:

Chromosomes, Giant Molecules, and Evolution by Bruce Wallace

What Evolution Is by Ernst Mayr

And also the paper

T. F. Cooper, D. E. Rozen, and R. E. Lenski. 2003. Parallel changes in gene expression after 20,000 generations of evolution in E. coli. Proceedings of the National Academy of Sciences, USA 100:1072-1077.

go away bobby.

I’ve Got “What evolution is” by Mayr.…nothing there.

Anyone care to present even one case of microevolution? I need to see the random mutation and I need to see natural selection – and I would preferably like to see them add a new morphological trait. Can someone just do this for me without giving me the runaround?

fly said:

Heck with macroevolution, microevolution has never even been validated. Never once has science pinned down a random genetic change that has been proliferated by natural selection. I’m here if anyone would like to present evidence to the contrary.

Have you ever tried googling “nylonase”?

myflyisdown said:

I need to see the random mutation and I need to see natural selection

You need therapy.

You mean you want to see things changing shape right before your very eyes, just like it happens in the cartoonies?

fly wrote:

“I need to see the random mutation and I need to see natural selection…”

Yea and I need to see the earth go around the sun.

On the off chance that you are serious, here is an oldy but a goody about the evolution of antibiotic resistance in bacteria:

Genetics 160:823-832 (2002)

If you are bobby this reference has been provided to you before. If you are not then perhaps you will read the paper and then admit that it gives a perfect example of exactly what you asked for.

yea, nylonase is actually 140 mutations. How do those arise randomly?

The question of macroevolution requires a new approach, for the evolution of man, as visible in the study of the eonic effect.

Consider commentary on this post at: http://darwiniana.com/2008/12/15/ma[…]le-to-study/

Will I EVER find a discussion group that does not denigrate others views by attacking the person? I was so enjoying this discussion, and then you had to start calling people IDiots. Please folks, keep it civil. Remember-once you label me, you negate me.

kathy

Once again Art erects a strawman and beats it down!

You go Art. I bet you are still proud of yourself!

What I mean is the way you have defined macro-evolution not even YECs reject the premise.

You guys seem to do that quite a bit. Take something that your opponent says then redefine it to suit your needs.

But anyway keep it up. Soon you will have torn down all the strawmen you erect.

And the good part is you don’t even know you are doing it.

IOW we are not laughing with you, we are laughing at you and your feeble attempts to support your faith.

kathy doolin said:

Will I EVER find a discussion group that does not denigrate others views by attacking the person? I was so enjoying this discussion, and then you had to start calling people IDiots. Please folks, keep it civil. Remember-once you label me, you negate me.

kathy

Once you say ignorant things, you will be considered ignorant. Be a grown up and accept the consequences of your actions.

Joe G is correct in this instance. ‘Speciation’ is far from denied by non-evos, even YECs use it as part of their explanations for the diversity of life! So it’s a complete strawman to argue that speciation (or ‘macroevolution’ or whatever you wish to term it) somehow defeats (or even bothers!) informed non-evos. Moreover, arguing that something is ‘on its way’ [I’m paraphrasing the last paragraph in the article] to being a proof of anything is meaningless in the case of evolution, considering evolution is a directionless phenomenon with no goals. That’s not to say this won’t be the first step, but for now it is all that it is.

saywhatyouwill said:

Joe G is correct in this instance. ‘Speciation’ is far from denied by non-evos, even YECs use it as part of their explanations for the diversity of life! So it’s a complete strawman to argue that speciation (or ‘macroevolution’ or whatever you wish to term it) somehow defeats (or even bothers!) informed non-evos. Moreover, arguing that something is ‘on its way’ [I’m paraphrasing the last paragraph in the article] to being a proof of anything is meaningless in the case of evolution, considering evolution is a directionless phenomenon with no goals. That’s not to say this won’t be the first step, but for now it is all that it is.

When you mention “‘speciation’ as used by Young Earth Creationists,” you are talking about the Baraminologists and related kooks who have explicitly stated that evolution does not exist (at the very least as described by scientists), yet also invoke a magical form of hyper-evolution of all living and extinct animals as having descended from pairs of ancestral “kinds” from Noah’s Ark on Mount Ararat only 4000 years ago, right?

I mean, you do realize that this “descent of “kinds”” is the same fractal-wrongness on par of a Holocaust denier alleging that not only did the Jews were not persecuted by the Nazis, but that Captain America should be brought to trial for having destroyed Dresden with his super-flatulence, or a conspiracy theorist claiming that the US government created the 9/11 disaster by shooting missiles into the Twin Towers and Pentagon, right?

Stanton said: When you mention “‘speciation’ as used by Young Earth Creationists,” you are talking about the Baraminologists and related kooks who have explicitly stated that evolution does not exist (at the very least as described by scientists), yet also invoke a magical form of hyper-evolution of all living and extinct animals as having descended from pairs of ancestral “kinds” from Noah’s Ark on Mount Ararat only 4000 years ago, right?

I mean, you do realize that this “descent of “kinds”” is the same fractal-wrongness on par of a Holocaust denier alleging that not only did the Jews were not persecuted by the Nazis, but that Captain America should be brought to trial for having destroyed Dresden with his super-flatulence, or a conspiracy theorist claiming that the US government created the 9/11 disaster by shooting missiles into the Twin Towers and Pentagon, right?

I won’t bother pointing out the logical fallacies, I’m sure you know they’re there. This link is quite a good starting point for understanding this ‘hyperevolution’: http://evolution.berkeley.edu/evosi[…]enecks.shtml. See also numerous studies of rapid evolution due to things like introduction to new habitats. Regardless, the original entry was setting up a strawman and beating it down.

saywhatyouwill said:

evolution is a directionless phenomenon with no goals.

False. The direction of evolution is toward higher numbers of offspring who themselves have offspring.

Dan said: False. The direction of evolution is toward higher numbers of offspring who themselves have offspring.

You misunderstand. Having more offspring is a result of chance mutations/adaptations that allow certain organisms to survive better than others. For instance, if an organism has a mutation that causes it to die out and become extinct, its ‘direction’ is obviously not towards higher numbers of offspring who themselves reproduce, it is towards extinction - there is no direction in mind (there is no mind). By direction, I was specifically meaning towards higher or lower complexity, towards new or reduced function, towards speciation or to remain in stasis. The original article implies that something is ‘on its way’ to becoming something else, but the organism(s) don’t have any goal or purpose in mind for this adaptation, they are not planning on creating a new organelle. If they do, it might be news, but for now they have not, so it is not. It also has no direction: this adaptation could prove very useful and allow more offspring, or it could prove harmful and reduce chance of survival. If evolution was directed solely towards what you believe, we’d still have the dinosaurs. But it is not directed, and so the dinosaurs died out (along with many more species).

“Natural selection is the simple result of variation, differential reproduction, and heredity — it is mindless and mechanistic. It has no goals; it’s not striving to produce “progress” or a balanced ecosystem.”

http://evolution.berkeley.edu/evoli[…]misconcep_02

No goals, no purpose, no direction.

The direction of evolution is toward higher numbers of offspring who themselves have offspring.

As I’ve read it, this simply isn’t the case on the ground. Having more offspring is one strategy. Having fewer but protecting them better is another. Having them earlier in the life cycle is another. The number of successful strategies (successful means, some organisms today use it and aren’t in danger of dying out) is very very large, and relatively speaking, only a small minority has adopted the strategy of spawning huge numbers in the hopes that a tiny fraction of a percent will survive to breed again.

If there’s been any trend toward one stragegy over another, I haven’t heard about it.

saywhatyouwill said:

By direction, I was specifically meaning towards higher or lower complexity, towards new or reduced function, towards speciation or to remain in stasis.

The word you used was “direction,” and I showed you the direction.

Now you’re saying that you didn’t mean direction, you meant “higher or lower complexity.”

Here we agree … evolution isn’t directed toward higher or lower complexity. There are high-complexity ways to survive over generations, and there are low-complexity ways to survive over generations – these are two of many different strategies for survival over generations. Stephen Jay Gould’s book Full House is a delightful discussion of this facet.

False. The direction of evolution is toward higher numbers of offspring who themselves have offspring.

Except in species that use the fewer but better-prepared offspring strategy instead of the larger-number-of-offspring strategy. ;)

Henry

I call on whatever gods there be to witness: here’s a bunch of scientists ferociously arguing with each other over the exact nuance of an interpretation of a description of a process they all agree on; but over there at DI and AiG, the lugenmeisters are in perfect accord in public and all is sweetness and light, even though they are at total odds with each other over virtually everything. Truly, humans are wonderful animals.

Dave Luckett said:

I call on whatever gods there be to witness: here’s a bunch of scientists ferociously arguing with each other over the exact nuance of an interpretation of a description of a process they all agree on; but over there at DI and AiG, the lugenmeisters are in perfect accord in public and all is sweetness and light, even though they are at total odds with each other over virtually everything. Truly, humans are wonderful animals.

Ah, but a new mechanism for speciation appears to be emerging. The groups look at each other and ask themselves, “Breed with that? Eeeww!”

Dan said: The word you used was “direction,” and I showed you the direction.

Now you’re saying that you didn’t mean direction, you meant “higher or lower complexity.”

Here we agree … evolution isn’t directed toward higher or lower complexity. There are high-complexity ways to survive over generations, and there are low-complexity ways to survive over generations – these are two of many different strategies for survival over generations. Stephen Jay Gould’s book Full House is a delightful discussion of this facet.

You showed me one direction that evolution can take, but eliminated all others (extinction, fewer offspring, etc.). If it can take numerous directions and lead to conclusions as diverse as greater, better adapted numbers, and complete extinction, then there is no direction inherent in evolution. What was the direction of evolution for trilobites? Extinction. What was the direction for bacteria? Greater, better adapted numbers. What I specifically meant by ‘direction’ was, I assumed, made clear by the context - something ‘on its way’ to being something else. But this is besides the point since there is no one direction of evolution - it goes where it goes based on chance mutation and natural selection. If you wish to believe in an end/direction that evolution has, perhaps you are a theistic evolutionist, and that’s fine. If, however, you believe there is no inherent ‘guide’, then it has no direction and can lead equally to a planet teeming with organisms or a planet bereft of any life.

saywhatyouwill said:

If, however, you believe there is no inherent ‘guide’, then it has no direction and can lead equally to a planet teeming with organisms or a planet bereft of any life.

First of all, I don’t “believe” anything concerning evolution. The word “believe” means to accept without doubt based on faith. Instead I “hold” to the concepts of evolution. The word “hold” means to accept tentatively based on evidence. Since new evidence is accumulating daily, we expect that the concepts we hold tomorrow will be different from (and more accurate than) the concepts we hold today.

Second, you claim that direction comes only with a guide. This is false. I have often hiked to mountaintops without any guide, just my making sure to step always in the upward direction.

Third, you’re right: at least one planet is teaming with life, but most planets are bereft of life. You seem to feel that this is some sort of problem for evolution, whereas in fact it simply reflects the facts.

Dan said: First of all, I don’t “believe” anything concerning evolution. The word “believe” means to accept without doubt based on faith. Instead I “hold” to the concepts of evolution. The word “hold” means to accept tentatively based on evidence. Since new evidence is accumulating daily, we expect that the concepts we hold tomorrow will be different from (and more accurate than) the concepts we hold today.

Second, you claim that direction comes only with a guide. This is false. I have often hiked to mountaintops without any guide, just my making sure to step always in the upward direction.

Third, you’re right: at least one planet is teaming with life, but most planets are bereft of life. You seem to feel that this is some sort of problem for evolution, whereas in fact it simply reflects the facts.

I’d love to know where I said there was any problem for evolution regarding the possible outcomes of successful life vs no life - I didn’t, and that is therefore a strawman. I used the fact that there are many possible outcomes merely to illustrate the fact that evolution (unless you believe it is guided, which was only ever a possibility when I mentioned it, not something I took for granted and as such renders your definitions of ‘believe’ and ‘hold’ pointless) has no inherent direction, something you seem either unwilling to admit or unable to grasp.

Your analogy of climbing a mountain is completely flawed in that it personifies evolution. You climb a mountain with a goal in mind - to get to the top. You plan your route ahead of time and prepare the necessary equipment, etc. All of this is a pre-planned guide, designed to ensure you go in a specific direction and reach your goal, as you say yourself: to step upwards. This is precisely what evolution cannot do - it has no mind, it cannot plan ahead, it is not aiming to reach anything. It could go up, down or roundabout. You may not have a sherpa telling you exactly what steps to take, but you clearly have a guide - your own mind which has goals and plans. The proper analogy would be of a robot that is simply programmed to walk about and happens on occasion to scale a mountain. But the robot can equally end up in a ditch or being hit by a car on the road. It doesn’t plan on any of these as it has no programming to guide it, direction. It simply goes where is goes based upon its programming, chance events, and a form of natural selection.

To bring this back to the original article. The adaptation could, over time, create a new organelle. Or it could cause serious defects which kill off the organism(s). Or it could remain as it is now. And there are many possibilities besides. Therefore, to say that it is on its way to any one of these outcomes is incorrect and illogical. It would be like claiming the wandering robot is on its way to climbing a mountain - it may happen, but until it does, it could equally be on its way to falling into a ditch or to walking into the sea.

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This page contains a single entry by Arthur Hunt published on November 21, 2008 9:20 PM.

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