Excellent dissection of Creationist Conflationary Confusion.
https://freethoughtblogs.com/pharyngula/evo-devo refutes evolution
Short version may be summarized:
Deuterostomes have a dorsal central nerve cord whereas Protostomes have a ventral central nerve chord.
Contrary to introductory textbook orthodoxy, this may be the only real distinguishing feature between the two.
It would be interesting to determine which was more ancestral.
88 thoughts on “P Z Myers nails it again”
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Loved the title: “ Pharyngula – Evolution, development, and random biological ejaculations from a godless liberal”
Apology & Request to moderators
I am less than cyber savvy and would appreciate a correction to the link
It should have been
Link to Pharyngula
Thanx in advance
Is that OK, Tom?
Alan
Alan Fox,
Perfect – big thanks
I’m guilty of prematurely predicting the demise of the “Intelligent Design” movement more than once. I wonder if the politicization of New Earth Creationism and its support of the extreme right working to undermine church-state separation has succeeded to the extent that the ID movement is now utterly redundant.
But then, by the same token, I wonder why YEC cargo-cult science exists at all.
Assuming that, as with individual development, evolution of physical life began with some sort of single-celled organisms. All of these organisms had the potential to evolve into creatures capable of conscious self-reflection. Life could progress to the point where it would be able to gain a modicum of understanding of itself.
From this basal starting point not all life would reach this potential. But if any part of this primal life was to evolve to have this capability it could do so only by relying other life forms remaining at earlier stages of evolution to provide a solid foundation.
In my opinion this is a realistic interpretation of animal sacrifice, and religious practices which involve killing individual animals is a corruption of this reading of that phrase.
It should be needless to say that every organism on the planet has had exactly the same amount of time to evolve, and in that time they have all achieved their current state of evolution.
Still, some lineages have been evolving far longer than others. Humans have possibly been evolving for nearly the least amount of time, perhaps less than a million years – maybe quite a bit less. By this measure, humans are far less evolved than most organisms.
CharlieM,
Hi Charlie
Do you see any support for the above assertion?
Which part of the assertion?
In general, diversity and complexity can result from almost any process. It’s not really support for evolution, though evolution will also have this result. Similarly, early development being complex neither refutes nor supports common ancestry.
Charlie seems to grasp the idea of deep time, but does not grasp the role selection plays over this time.
This is a rather odd phrase.
Every cell of every organism is a cousin of every other living cell, but cells of different organisms replicate at different rates, and germ lines differ radically in this respect.
PZ Myers 🕷
“Homosexuality is not a significant barrier to reproduction.
PZ Myers 🕷
“While gay men & lesbians who want children, if we remove artificial barriers, can easily have them, with cooperative partners.”
PZ Myers nails it each time he opens his “mouth” or keyboard … lol
You are basically saying that humans have had no antecedents which were evolving before we took on our current bipedal, primate form. So in your opinion, “humans are far less evolved than most organisms”. Since splitting from LUCA, a multi-cellular, bipedal, self-conscious primate is less evolved that a single-celled prokaryote? A single-cellular stage is not part of our evolution?
It’s possible to support the claim that chance and time can produce complexity, but I see very little support in the belief that this can produce the sentient creatures of present times. Judging by “survival of the fittest”, prokaryotes would seem to be the pinnacle of evolution.
We would have to define “”engineer” as a being with capabilities infinitely beyond those of human engineers to account for life. I don’t think in terms of either blind processes and time, or engineering being responsible for evolution.
That was not my take on what Flint wrote at all. You appear to be indulging is a bad case of “So what your saying is…”
And no, you were not asking for clarifcation.
From a molecular biologist’s perspective, absolutely. No matter how many times this is explained, it never seems to sink in: far from being an intricately co-ordinated system where everything is just so, as it must be, vertebrates appear to be a Heath-Robinson hodge-podge of kludges.
Bacteriophage, they’re the highly evolved, highly optimized ones.
Ah, how British. In America, the allusion is to Rube Goldberg. But now I’m also aware of Heath-Robinson, so thanks for that.
You are right, I’m not asking Flint to make things clearer in my mind. I am trying to get him to think about the consequences of what he is saying so that he is clear about what he is saying.
Maybe I’ll need to ask a passing bacteriophage to draw me a picture of the course of evolution. Oh wait! Silly me, it can’t do that on account of it being deaf, dumb and blind. 🙂
Here’s a question or two for you.
The form of some species of coelacanths appear to have been virtually unchanged for over 400 million years, and the recognizable human form for maybe 100000 years, in your opinion, which, if any, is the most highly evolved and what is your criteria for making this determination?
How do you account for us ‘kludges’ still being extant against all these evolutionary odds due to competition from highly evolved, highly optimized, ‘superior’ life forms?
These types of machines are famous for using very complicated, convoluted means to achieve simple outcomes.
Therefore, by DNA_Jock’s logic, the result of achieving self-consciousness, technologically enhanced senses, planet wide communications taking hardly any time, exploration of the cosmos, etc. should be simple, right? So why haven’t the likes of viruses and prokaryotes achieved any of this by more direct means? How hard can it be?
That statement is false, like I already told you!
You appear to be incapable of learning things that do not fit your preferred narrative. Does that not worry you?
What you’re doing here is called the Texas Sharpshooter fallacy. You have set it up so that YOUR species is the pinnacle of evolution, and then decided that every other species must fall short. Those most different from you fall the shortest. DNA_Jock used different criteria – ” an intricately co-ordinated system where everything is just so, as it must be”, and pointed out that vertebrates are Johnny-come-lately species a very long way from optimized, a “hodge podge of kludges”. In other words, exactly the opposite of what a billion years of evolution would produce. Humans have backs not yet appropriate for standing upright, feet not yet appropriate for walking, our knees are accidents waiting to happen (and often do), and a hundred other shortcomings evolution would eventually rectify. Even human childbirth is dangerous because our hips aren’t appropriate for our heads!
Why would you expect prokaryotes to become more like humans? They are far better at what they do than we are at what we do – and do not destroy their environment in the process, as we are doing.
As noted by Corneel, your premise is false, although it was smart to include the escape hatches of ‘appear’ and ‘virtually’ and ‘recognizable’. Yawn. In MY opinion, since you asked, ‘most highly evolved’ is incoherent, so there aren’t criteria. We’ve all been evolving for the same amount of time, although stasis is the norm.
What a silly thing to write. We aren’t in competition with these guys. In lot of cases they are helping us out. Although when push comes to shove, they generally whoop our sorry asses; we’ve been doing a little better thanks to tool use in the past 100 years, but that’s a blink of the eye. We could well pollute ourselves to extinction in the next 100 and the plants and arthropods will do just fine.
We just got stuffed up well and good by a virus with a 30kb genome! Talk about efficient!
I’m guessing this is more references to tool use. Yeah, go humans.
Viruses and procs haven’t gone down this pathway, because they don’t need to. They are doing just fine as it is, thank you very much.
We have covered your hilariously anthropocentric criteria for success MANY TIMES previously; whether it’s digital wristwatches, New York and wars, or moose taught to sign complicated insurance forms; you keep coming back with the same tired rubbish. You just cannot seem to understand how ridiculous your pleas for human exceptionalism are.
I will note that, were bonobos to develop the atlatl and start hunting humans, then I reckon our response would be genocidal. There’s a certain inhibitory effect of having a ruthlessly self-centered ubiquitous apex predator: they don’t tolerate competition.
Careful there, mate. If you don’t watch out we’ll have Bill showing up on this thread to baldly assert that you are guilty of ‘the labeling fallacy’. Although I do giggle everytime he self-pwns in this way.
I have this wonderful New Yorker cartoon, where the psychiatrist says to the patient on the couch “You say you have nameless fears? No problem, we have a name for everything.”
Fossil evidence suggests that the human lineage is comprised of a pretty hefty number of extinct variations, the most recent being Neanderthal and probably Denisovan. Various age indicators also suggest that as many as half a dozen related hominin species were extant concurrently.
I guess there’s some debate as to whether these competed or interbred or died out for some other reason, but it’s thought-provoking that today there’s only one, our closest relatives are both not very close, and not very aggressive.
Your claim that my statement is unquestionably ‘false’ is very emphatic, and does nothing to further the discussion. My statement can be true or false depending on what is meant by ‘virtually unchanged’.
Your post where you ‘told’ me that I was wrong was not the final word in that discussion. There were further exchanges in our discussion on this.
The image below was copied from here.
In this video, Perry gives his answer to the question posed in the title, and the answer is, no, caelocanths did not stop evolving. He goes on to say that they are in phenotypic stasis, they haven’t changed very much. I think that is a fair assessment that I hope we can both agree on. Despite their differences all the species in the image below are recognizably caelocanths. But observing that any one species of bird or mammal is descended from lobe-finned fishes is not so obvious. Why would that be?
There is this to consider:
In the case of caelocanths, the palaeontological record makes clear that the this order of lobe-finned fishes evolved from lobe-finned fishes nearly 400 million years ago during the Devonian, and are therefore members of the Sarcopterygii.
Relative to birds and mammals, caelocanths have remained more or less unchanged. That is what i meant by, ‘virtually’.
But I don’t think our species is the pinnacle of evolution as it is understood by orthodox biologists. We fair pretty poorly when evolution is judged in such a way.
Where we come in to our own as a species is in the evolution of consciousness, communication skills, foreknowledge, acquisition of information, that sort of thing.
It’s amazing how many people think they are experts when it comes to knowing how to design mechanical systems.
For over 70 years, I’ve been standing, sitting, squatting, lying down, walking, running, climbing and jumping, with very few problems to show for it. Funny that! 🙂
Of course there have been occasions when I have abused my body and suffered the consequences of my actions. But I find that if I treat my body in the appropriate way, it will serve me well.
I neither expect nor want prokaryotes to become more human-like. I have my existence as a thinking human being thanks to the likes of prokaryotes remaining prokaryote-like.
They are not escape hatches, they are the facts as I see them. Extant caelacanths are never perfect copies of any extinct caelacanths that have been found as fossils. These words I use are relative terms and as such the relationships are open to discussion.
That’s the thing with competition. What seems to be competition on one level turns out to be cooperation at a higher level. As you say, they quite often help us out, and I would say we are reliant on their help for our continued existence.
Speak for yourself. I came through it with very little effect. And as a species we haven’t been killed off. I do have a great deal of sympathy for those who were and will be seriously affected by it, but in evolutionary terms could it be classed as being “stuffed up”?
We humans are exceptional in that we are the only creatures on the planet who are at the stage of accepting responsibility. The future of the planet depends on us knowing the impact our species is having, and in taking responsibility for our treatment of the planet. Which other species has had such an evolutionary trajectory?
The general rule of evolution may be “every species should try to maximize its continued survival regardless of the fate of other populations”, but we no that this cannot apply to us.
How useful is the term, “species”, when comparing, say, the primates to bacteria?
Interesting findings can be obtained in the study of the behaviour of individual primates within groups, but it is not the same when studying interactions of single bacteria within a culture. Individual traits are much more diverse in higher animals than in prokayotes.
Some evolutionary lines tend more towards individuality than others.
This is effectively “not even wrong”, Charlie.
Convergent evolution 🙁
🙂
Speak for yourself. Do you think that you and the person next to you in the street have no more individual differences than two bacteria next to each other in a culture dish? It would be interesting to see if anyone else agrees with this.
They all look the same to Charlie. This, and Mating Type Switching, have all been covered before.
CharlieM,
Not what I meant, Charlie. I mean your statements have too little content to disagree with.
It appears that the only thing that remained virtually unchanged is your stance on this issue since the last time this came up. Yes, we did discuss this topic in that old thread and at that point eventually you toned down your claim to:
which is a statement that can be reasonably defended IMO. But now, two years later you have forgotten all about that exchange and repeat your old mistaken claim:
which is flat wrong. There are only two species of coelacanth alive today and neither of them remained “virtually unchanged” since the Devonian for any reasonable interpretation of “virtually unchanged”.
I am sorry if my tone has grown a little more fierce in the meantime, but a different approach seems justified as the first time clearly didn’t take.
Actually, what he said is: “If we compare them to mammals they haven’t changed much at all since the extinction of the dinosaurs”. This I can agree with, but this is a very different claim from yours. I note that he also said :
That’s you, I believe.
You actually have problems with recognizing tetrapods?!? Really?
Yes, well in that case you are ‘virtually’ wrong. Personally, I think the only thing showing stasis is the development of your contributions here. You are repeating yourself and appear not be benefiting from your interactions with the other members. This is a real shame!
Corneel,
Are there lineages, at least among larger animals, that have evolved very little over very long periods, or is evolution something continuously happening even when this isn’t obvious in outward appearance to the layman? You know, things like some sharks or some horseshoe crabs or whatever.
Flint,
Something to be aware of is that, just because there is no outward, gross morphological change apparent, that does not mean that there is no evolution going on.
In particular the Red Queen hypothesis with respect to host-parasite relationships.
(Predator-prey is likely to involve morphology changes, host-parasite less so…)
Your theory needs hypotheses like a sinking boat needs patching. Still, it’s ultimate faith will be the same.
It’s all on the inside then? Obviously you have proofs from the fossil record? Or will you confirm this is another unsupported crazy “hypothesis”?
Now do the dog, dawg. Oh wait, you mean to say any variability and adaptation is chalked up to “evolution”? In that case your burden of proof is gone – you know – the “origin of species”. All you show is acquired immunity, sun tanning and animal breeding and just imagine the rest. Hollywood style.
I forget. Is it passe to point to different human races and call that “evolution”? Wasn’t Darwin fond of that?
Well, the whole point of this conversation was that these “inside” changes don’t show up in the fossil record. Instead, we can look at the DNA sequences of a wide variety of animals and see that the proteins involved in immune response diverge faster than similar proteins involved elsewhere, as predicted by the Red Queen. Receptor tyrosine kinases are a case in point. 🙂
I sense a certain fear around some quarters. It’s to do with giving ammo. to creationists. Any hint of the immutability of species must be quashed to prevent them using it against arguments for evolution. I’d like to make it clear that I don’t believe in the immutability of species. On saying that I’m sure it will be obvious to anyone who follows my arguments that I don’t believe that evolution is ultimately blind.
Back to the good old caelacanth:
Earliest known coelacanth skull extends the range of anatomically modern coelacanths to the Early Devonian
Some posters here seem to be under the impression that I deny caelacanths have undergone 400 million plus years of evolution. That isn’t the case. As I said in 2021, there is no doubt that coelacanths have evolved.
As for them being living fossils, I have never described them as such. As can be seen in the link above, I even gave a link to an article in Scientific American, “Coelacanths are not living fossils. Like the rest of us, they evolve”. I don’t think that it is such a big deal if some people like to call them living fossils. As I see it, this phrase is probably frowned upon due to the fact that creationists are fond of it.
There were a greater variety of caelacanths swimming about in those prehistoric times, but I don’t think the two known extant species would have looked out of place along with their ancestors in those ancient waters. On the other hand, someone like me with his trousers rolled up to the knee and a knotted hanky on his head, paddling in the shallows, is a scenario to be confined to the realms of science fiction. I have a feeling that back then our ancestors would also have been swimming around with all the other fish-like creatures. We have come a long way since then. I liken it to the difference between myself as I am now to how I was as a 4 week old embryo. Meanwhile, unlike some of their relatives, caelacanths remain trapped in their watery environment.
Look at the above diagram and make note of the time they attribute to the appearance of anatomically modern coelacanths.
I would like to stress the difference I see between individual difference and individuality.
For instance, we can look at a pair of twins, one a girl and the other a boy. Their individual differences are clear enough. But their separate individualities transcend these differences. When I say individual traits, you can take it I mean instances of individuality.
A further example: I knew a man who had a large port wine stain birthmark on his face, and I also know people with tattoos on their faces. The former is an individual difference, the latter are the result of people displaying their individuality.
As I see it your Salmonella examples are examples of individual differences, not individuality. Individuality has to do with personality and self-determination. You won’t find many bacteria booking themselves an appointment with the colony’s specialist in flagellar enhancement. 🙂
Fair enough. But content is in the mind’s eye of the beholder. Even though they live in a world of sound, what meaningful content would there be to a bat up in the rafters of the Globe Theatre listening to a Shakespeare play?
For ‘virtually unchanged’, you can take it I mean, anatomically modern in appearance as in the above diagram.
No need to apologize. Feel free to use whatever means you find appropriate in putting your point across.
You believe wrong. As I said at the time, I believe coelacanths have evolved.
Why does he choose the time of the dinosaur extinctions as his point from which coelacanth stasis is observed? Well look at the diagram below. It shows slight divergence of lobe-finned fishes which includes lungfish. We cannot tell from that diagram how coelacanths diversified prior to the end of the Cretaceous. But one thing is clear, if they did indeed diversify it was very limited and most of the lines died out during this time.
No I don’t have that problem. It is immediately obvious that the coelacanth caught in a fisher’s net is a lobe-finned fish. It is not immediately obvious that the adder crossing my path is a tetrapod.
But anyway, how do you know that tetrapods are in fact the direct descendants of lobe-finned fishes, and that tetrapods and lobe-finned fish are not both descended from a common ancestor?
CharlieM: Relative to birds and mammals, coelocanths have remained more or less unchanged. That is what i meant by, ‘virtually’.
Yes, well in that case you are ‘virtually’ wrong. Personally, I think the only thing showing stasis is the development of your contributions here. You are repeating yourself and appear not be benefiting from your interactions with the other members. This is a real shame!
Believe me, I do benefit from these interactions. What I find a shame is when arguments become focused on nuances of word meanings and not on the actual discoveries of life, its history and its relationships.
Not sure how this applies to prokaryotes. Are you saying that microbes are different individually, but have no apparent differences in personality?
Flint,
Based off what he wrote contrasting the port wine stain with the facial tattoo (and all that prior guff about choosing to be vegan…), I think he’s trying to draw a distinction between (boring, mundane) inherent differences between individuals, and those super-cool differences that are the product of their different decisions. But it’s pretty opaque.
He’s headed for another disappointment, I suspect.
Yes.
On the contrary, the wisdom displayed by nature is far superior to any decisions made by sentient individuals, however wise they may considered to be by that individual.
Participating here never disappoints me. 🙂
Speaking generally, the decisions made by nature are entirely trial and error, mostly error. Unlike nature, people can learn from both their mistakes and the mistakes of others. People have gradually figured out that education matters, and except for Republicans, we value education (though education is losing ground as some people realize it’s a threat!)
But your participation disappoints anyone who reads your posts expecting you to have learned from being corrected so many times. Nope, never happens.
Oh dear. The topic of conversation was what you meant when you drew a distinction between “individual difference” and “individuality”. So your prattling about “far superior wisdom” is just further smoke.
Well, given that your only goal is to write things that make you feel better, regardless of context or relevance, it would be deeply unfortunate and rather surprising if this were not the case. 😉
Difficult to answer. Things like physiology, genome architecture and behaviour don’t fossilize so we are restricted to studying morphology, mostly of the hard bits. As Jock already remarked, we have good reason to suspect that certain aspects, like the immune system, are always subject to selection. Large animals also tend to have relatively small populations so will always be subject to evolution by genetic drift. For these reasons it is very unlikely that species that have remained morphologically similar also evolve slowly in non-morphological traits.
ETA: Just noticed you included sharks. Since there are so many species of extant sharks, we do have a fair idea of evolutionary divergence by simply looking at diversity of extant species. In fact, sharks are fairly diverse group occupying various niches world wide.