Convergent evolution? Crown of Thorns starfish shows “surprising” chordate-like gene organization

AVS:

Like I already said Mungy, we do know what makes an organism what it is: it’s genome and the differential gene expression of that genome.

Evidence please. The typical propaganda means nothing without evidence.

Yes, Joe, what are your thoughts on why dolphins and whales have such large brains in comparison to body size?

Intelligent design

Why not just increase gill size so as to have a larger surface area for gas exchange?

LoL! As if that will put O2 in the water. There are water-worlds which lack dissolved O2 and the fish are air-breathers- see the the Arapaima of the Amazon

The large brains of dolphins and whales can’t be due to the evolution of these species from ancestral mammals could it?

There isn't any evidence that such a transformation is possible. So that would be a problem. Joe

The theory of evolution doesn't exist so no, it does not provide a robust explanation. Zachriel is just another insipid troll. Joe

CharlieM: Can you tell us what that niche is? Intelligent, tool-using, social apes. CharlieM: Pick any species with an opposable thumb and tell me what they have achieved by using this feature and let us see how it compares with human achievement. Human achievement? Humans are the only organism with opposable thumbs to build skyscrapers, but not the only one to wage war. CharlieM: On its own the possession of an opposable thumb does not count for much. It was your example. CharlieM: Why has the pentadactyl limb persisted throughout the evolution of land vertebrates? Common descent. CharlieM: ... Individuals build nests in preparation for the coming of their offspring... Sure. Zachriel: Do you have scientific evidence of any sort to support your conjecture? CharlieM: you say that when looking at the larger scale of the history of life, everything changes and this does not apply. Notably, you didn't answer the question. CharlieM: What reasons do you have for thinking that it does not apply? Because the Theory of Evolution provides a robust explanation without having to make such extraneous suppositions. The primary mechanisms are common descent, natural selection, reproductive isolation, and extinction. Zachriel

Sorry my computer crashed and I seem to have lost the edit function on my last comment. Oh well! Seasons greetings to all. CharlieM

Hi Zachriel.

You wrote above: Of course there’s a niche.

Can you tell us what that niche is?

You wrote: Nor are humans the only organism with an opposable thumb.

Pick any species with an opposable thumb and tell me what they have achieved by using this feature and let us see how it compares with human achievement. On its own the possession of an opposable thumb does not count for much. But regarding the human organism as a whole it is ideally suited to creative work. A large brain, limbs freed from the task of support and/or locomotion, 'multiuse toosl' at the end of those limbs, the enhanced sense of touch at the ends of those 'tools'; all this and more taken together contribute to the creative capacity of humans. Why has the pentadactyl limb persisted throughout the evolution of land vertebrates? You might say that evolution must just use what it is given. Well I would say we are very fortunate that this limb was given in the first place. And all those specialists did not just use what they were given, but they changed the limb out of all proportion but it is still based on the original form.

I wrote: But this does not mean that it wasn’t prepared in advance for its use in present day humans.

You replied: You could conjecture so, but it seems contrary to what we have discovered about the history of life. Do you have scientific evidence of any sort to support your conjecture?

I would say that its only contrary to a biased, materialistic understanding of life. Preparing for the future is ubiquitous throughout all levels of life. To give some examples. Intra-cellular and intercellular transport moves pre-assembled molecules to places where they will be required in the future. The organism is pre-planned in the seed or the egg. Organisms ingest substances in advance of their need to build their structures and provide themselves with energy. Individuals build nests in preparation for the coming of their offspring. The tadpole is water dwelling, water breathing creature which is a preparation for an air breathing land dwelling amphibian. The, relatively unconscious, unaware baby is a preparation for the self conscious, aware adult. Species migrate, some of them over vast distances, in order to reach suitable breeding grounds. They do this in preparation for what will happen in the future. Everywhere we look life is in the process of preparing for what is to come. And you say that when looking at the larger scale of the history of life, everything changes and this does not apply. What reasons do you have for thinking that it does not apply?

CharlieM

lifepsy: Alleged convergence can’t even be identified until you demonstrate homology as a reference point. Homology is based on the assumption of the absence of convergence. That is incorrect. Homology is a determination based on evidence, not an assumption. Darwin: It is incredible that the descendants of two organisms, which had originally differed in a marked manner, should ever afterwards converge so closely as to lead to a near approach to identity throughout their whole organisation. lifepsy: Religious darwinian mysticism. Darwin's statement has been repeatedly supported by the evidence. Mung: Why would it “make more sense”? The nested hierarchy and fossil succession strongly support the evolution of the vertebrate limb. CharlieM: The human forelimb is the most general example of the pentadactyl limb found in vertebrates. It has no niche because it is capable of a multitude of functions. Of course there's a niche. Nor are humans the only organism with an opposable thumb. CharlieM: But this does not mean that it wasn’t prepared in advance for its use in present day humans. You could conjecture so, but it seems contrary to what we have discovered about the history of life. Do you have scientific evidence of any sort to support your conjecture? Zachriel

Hi AVS excuse me butting in, but: You wrote to Mung:

It makes much more sense that there was a common ancestor with a humerus, radius, ulna, etc. whose descendants kept this skeletal plan and went through small changes over the course of evolution to suit the varying selection pressures.

My comments: The human forelimb is the most general example of the pentadactyl limb found in vertebrates. It has no niche because it is capable of a multitude of functions. On the other hand we find versions of the pentadactyl limb which are specialised to varying degrees. And the more specialised it is the less likely it will allow its owner to progress beyond its observed niche. So, rather than the human forelimb being at the end of a blind process of change, the evidence points to it being the reverse. All other vertebrate limbs have taken the general human type plan and narrowed its function down to suit their specialised function. Getting back to my "parts are a reflection of the whole" from #49; as an embryo develops, structures and organs emerge in advance of the function/s that they have in the fully formed organism. Likewise the pentadactyl limb appeared in advance of the appearance of humans. But this does not mean that it wasn't prepared in advance for its use in present day humans. And also:

I’m simply asking why dolphins and whales have this huge brain that they must supply with oxygen despite living in an oxygen poor environment; meanwhile sharks are doing just fine in the same environment with a small brain and gills (the more suitable organ for gas exchange in an animal that spends its entire life in the water

Isn't that a question you should be asking a believer in the current paradigm? How have dolphins and whales managed to survive in an environment that their respiratory system makes them so poorly adapted to? Are you saying that they have thrived in their environment despite their respiratory systems? So we may look at an animal and say that it is successful in the survival race because of a certain feature but, on the other hand, it may be successful despite a certain feature. This tells us everything and nothing. CharlieM

CharlieM, I like to think so. Hopefully you will keep posting. It's not always easy for a holist to feel quite at home here at UD. However, one can reach the conclusion that arguing for information and organization (irreducible complexity) is in full accord with holism, since these concepts can be regarded as stemming from a holistic view. However, it is holism constrained by the empirical demands of science. The problem for our position is that the wholeness of things is not directly measurable. Box

Hi Box, I'm glad you enjoyed my post. From reading other threads I think we have a somewhat similar outlook. CharlieM

Like I already said Mungy, we do know what makes an organism what it is: it's genome and the differential gene expression of that genome. You're starting to not make sense though, try to stay here on Earth. As I said, you expect us to believe that the vertebrate limb skeleton evolved thousands of times with no change in the overall structure to suit very many different needs? No. It makes much more sense that there was a common ancestor with a humerus, radius, ulna, etc. whose descendants kept this skeletal plan and went through small changes over the course of evolution to suit the varying selection pressures. And don't put words in my mouth, I certainly did not say that they evolved from mammals with smaller brains, nor did I say that larger brains always evolved from smaller brains. Overall, mammals have a much larger cerebrum than other animals of comparable size, the dolphins and whales have retained this size increase. I'm simply asking why dolphins and whales have this huge brain that they must supply with oxygen despite living in an oxygen poor environment; meanwhile sharks are doing just fine in the same environment with a small brain and gills (the more suitable organ for gas exchange in an animal that spends its entire life in the water). AVS

AVS:

The large brains of dolphins and whales can’t be due to the evolution of these species from ancestral mammals could it?

You mean they evolved from mammals with smaller brains? So larger brains always evolve from smaller brains? Mung

AVS:

So lifepsy, you’d have us believe that the vertebrate limb evolved many different times, with virtually the same skeletal plan each time, in order to function in many very different ways? Wouldn’t it make more sense that vertebrates evolved from a common ancestor, retained the same skeletal limb plan, and these limbs adapted different functions?

Why would it "make more sense"? Mung

AVS:

We don’t know what makes an organism what it is? What does that even mean?

It means, my dear AVS, that to say that X is an instance of Y is to make a metaphysical claim. Mung

Yes, Joe, what are your thoughts on why dolphins and whales have such large brains in comparison to body size? Why not just increase gill size so as to have a larger surface area for gas exchange? Sharks seem to be doing just fine with their small brains and large gills. The large brains of dolphins and whales can't be due to the evolution of these species from ancestral mammals could it? Noooo, of course not. That would just make too much sense. AVS

CharlyM #49, Thank you for your thoughts. I especially enjoyed the part on the "rise of bipedalism". Box

So lifepsy, you'd have us believe that the vertebrate limb evolved many different times, with virtually the same skeletal plan each time, in order to function in many very different ways? Wouldn't it make more sense that vertebrates evolved from a common ancestor, retained the same skeletal limb plan, and these limbs adapted different functions? Many branches of the tree of life fit quite well together, showing gradual adaptations when you go with the second one. But if you'd like to continue ignoring the evidence then go right ahead. AVS

Zachriel, It’s not circular because the overall nested hierarchy remains with convergence being the exception. Alleged convergence can't even be identified until you demonstrate homology as a reference point. Homology is based on the assumption of the absence of convergence. “It is incredible that the descendants of two organisms, which had originally differed in a marked manner, should ever afterwards converge so closely as to lead to a near approach to identity throughout their whole organisation.” — Darwin Religious darwinian mysticism. lifepsy

AVS Similar structure/function relationships are used to infer relation, lifepsy? Yes... what do you think homology is? Homology is based on the fundamental assumption that a certain amount of complexity can not have multiple independent origins. This is the flimsy, undemonstrated basis supporting all of phylogenetics. lifepsy

I think that we need to get away from the gene centred, reductionist view of evolution before we can make any further progress in understanding life and evolution. The following are some observations that I believe fit the facts better than the current materialistic teaching on evolution. This is my personal opinion and just because I believe it to be close to the truth I don't expect every other person to do likewise. I have a holistic view in which I regard all of earthly life as a unity. The various forms are an individualised expression of that unity and individual, multicellular organisms are each a unified entity within the unified whole of life. When we regard the unity of an individual we must think of it as a unity in time as well as space. For example when we think of a rose we usually bring up a mental image of the flower, stem and a few leaves, perhaps even in a vase, but this is not the rose in its essence. That would be analogous to the 1812 Overture consisting only of a few canon shots. A rose, as a unified whole, is a dynamic entity which includes a progression from seed to mature plant. Earthly life is a unified whole from its origin to the appearance of self awareness in the human being. Everything is a building up towards the manifestation of self awareness in the form of the human. As physical life proceeds towards this end it is built from the base up on forms which remain at an earlier stage of development just as the individual human body must retain basal cells as its form develops. The bi-lateral form is on a direct line leading to self aware forms of life, the radial form is a side branch. The following transition can be used to describe the progression of life as a whole and also the progression of the human individual: From single cell, through water dwelling, tetrapod form, petadactyl limb, air breathing, from quadrupedalism to bipedalism, able to express its inward feelings by emitting sound, and finally producing the capability of rational thought and communicating these thoughts to others. The parts are a reflection of the whole. Now as our individual organs don't spring into existence by chance out of nothing, so the individual animal forms do not spring into existence by some random, undirected process. The animal forms are individualised expressions of the overarching type. The feline nature exists over and above the individual cat and it is this which determines the form of its body, how its limbs are shaped, how its teeth and claws take on the form that they do. The genes are not the cause of the form, they are only the means by which the physical form is able to be expressed. Many marsupials exhibit surprising similarity to their placental cousins. Due to their very similar natures they express the type in a similar way. The individual organism can be seen with the eye, the type cannot. But it can be seen. By using the mind as a sense organ the type can be observed. Invoking convergent evolution explains nothing. Take a look at the rise of bipedalism. We can say it is a demonstration of convergent evolution. What then? This explanation provokes no further though on the matter. But if we study the rise of bipedalism and think of it as a progression towards being able to use the limbs in a creative way, we can see a pattern. We humans have freed our forelimbs from the task of providing us with a means of locomotion and in so doing they become available for a much more creative use. Ever since land animals emerged from the water we see the striving for bipedalism in their forms. We see a hint of it by observing the difference between newts and frogs. Reptiles normally scuttle about on all four limbs or even none at all, but in some cases we see the beginning of bipedal motion. Look at dinosaurs, they attain bipedalism in creatures such as theropods, but in so doing their forelimbs become stunted. Each stage takes bipedalism to a new level and in birds we see the most advanced form of this arrangement. But birds have overshot the mark so to speak. They haven't actually freed their forelimbs for a higher purpose they still use them for locomotion; and in those that have lost the ability to fly, as in the ratites, their wings degenerate. Because we humans have freed our forelimbs from the task of support and locomotion we can use them to create the human made wonders we see all around us. Those are a few of my thoughts. CharlieM

Yes, AVS, design requirements. Obviously you have never studied design nor been part of a team who had to have different equipment play together without human interference.

You’d think the ability to take in oxygen while underwater would be a design requirement for an animal that lives its entire life in the water such as the dolphin, but we don’t see that do we?

Not enough O2 underwater to support their large brain. The design of the dolphin requires more O2 than is available underwater. Anything else I can help you with? Joe

Design requirements huh Joe? You'd think the ability to take in oxygen while underwater would be a design requirement for an animal that lives its entire life in the water such as the dolphin, but we don't see that do we? You're just making things up now Joe, talking out of a hole that isn't your mouth. AVS

AVS:

Then why are the dolphin, ichthyosaurus, blue marlin, and penguin scattered throughout the vertebrate tree?

Because those organisms, while similar due to a common design, are also different due to different design requirements.

What about birds and bats?

The differences outweigh the similarities.

The structural similarities in distantly related species are adaptations to similar selective forces and are defined as convergent evolution.

That's the propaganda anyway. Joe

Similar structure/function relationships are used to infer relation, lifepsy? Then why are the dolphin, ichthyosaurus, blue marlin, and penguin scattered throughout the vertebrate tree? What about birds and bats? If structure/function relationships were used to define lineages, wouldn't science say these species are closely related? But it doesn't . Why? Because relationships are not inferred by simply looking at overall body plan structure and functions like it seems you are saying. Instead, as I already said, evolutionary relationships are constructed based on fossil data, genome analysis, etc. The structural similarities in distantly related species are adaptations to similar selective forces and are defined as convergent evolution. AVS

Gradual evolution does NOT predict an objective nested hierarchy and there isn't one to be had wrt prokaryotes. Zachriel is obviously proud to lie for evolutionism. Joe

lifepsy: interesting circular reasoning It's not circular because the overall nested hierarchy remains with convergence being the exception. "It is incredible that the descendants of two organisms, which had originally differed in a marked manner, should ever afterwards converge so closely as to lead to a near approach to identity throughout their whole organisation." — Darwin Zachriel

AVS, By combining evidence from fossils, genomic analysis, etc.... Actually that is a great way to objectively determine how distinct and separate different types of life really are. in order to put together estimates of lineages. "estimates of lineage" also known as darwinian imagineering. lifepsy

AVS, If two organisms demonstrate similar structure/function relationships and these organisms are not closely related, then it is an example of convergent evolution. What kind of objective check would you be looking for? interesting circular reasoning, AVS... similar structure/function relationships are the very criteria used to infer relation in the first place. the entire basis of homology is the assumption that the traits in question can not have an multiple independent origins. it is a weak inference based on the assumption that universal common descent must be true. lifepsy

We don't know what makes an organism what it is? What does that even mean? It's just another favorite nonsensical argument of creationists. If you want me to sum it up as simply as possible, we do know: different organisms have different genes and these genes undergo differential gene expression. AVS

Thank you Mung. I musta forgotten those rules. Joe

If we don't know what makes an organism what it is your evidence is subjective at best. Joe

By combining evidence from fossils, genomic analysis, etc. in order to put together estimates of lineages. So, what kind of objective check are you looking for? AVS

Joe, If the genomes are of similar size, then they are closely related. If that doesn't work, then if the genomes are similar then they are closely related. If that doesn't work, then if some of the genome is similar then they are closely related. If that doesn't work, then if they look alike they must be closely related. If that doesn't work, they must be closely related. If that doesn't work, then it must be convergent evolution. Honestly, I get tired of explaining this evolution stuff to you over and over. You really need to pick up your game. Mung

How can you tell if they are related or not? Joe

If two organisms demonstrate similar structure/function relationships and these organisms are not closely related, then it is an example of convergent evolution. What kind of objective check would you be looking for? AVS

The funny thing is that evolutionists will never be able to define any actual limits to convergent evolution. To the evolutionist, whatever is deemed to have to have convergently evolved, convergently evolved. There is no objective check for such a thing. All they can do is endlessly speculate about an amount of convergence they personally feel would be unlikely. It's exactly the type of scenario one expects with pseudo-science. lifepsy

http://www.tolweb.org/Echinodermata http://www.differencebetween.com/difference-between-chordates-and-vs-echinoderms/ Mung

wd400:

I can’t see how a radial adult arising holding on to a linear arrangement of hox genes is more or less surprising under evolution or ID.

But you can, of course, contact, email, the authors and ask them the reason for their surprise. Here's what I said:

Looking at their fossil remains, it would appear to be a body-plan formed by an iteration of the basic chordate plan. Unusual. But, since we’re dealing with the basic chordate plan, the linear array of Hox genes might not be such a surprise after all. However, this also might mean that its true phylogeny might lie outside of the echinoderm lineage.

I will translate, and leave it at that. It appears that in animals with a radial body-plan, the Hox genes are NOT in a linear order. In bilaterians and chordates, they are in a linear order. So, AFTER the rise of the echinoderms, you have an echinoderm exhibiting a radial body-plan, and its Hox genes ARE in a linear order. How can that be? Did the echinoderm pattern "converge" onto that of the chordates? Or, did the bilaterian body-plan, as I suggest, employ its linear order in a five-fold manner? Again, unusual. And, begging the question as to the phylogenetic roots of the starfish. PaV

bornagain77: perhaps you should buy and read Darwin’s Doubt, with an open mind, where the Ediacaran organisms, Jellies, and Sponges, are covered and shown to be non-ancestral to the Cambrian Biota We didn't reference jellies or sponges, but bilaterians. See Fedonkin & Waggoner, The Late Precambrian fossil Kimberella is a mollusc-like bilaterian organism, Nature 1997. Zachriel

Zach, perhaps you should buy and read Darwin's Doubt, with an open mind, where the Ediacaran organisms, Jellies, and Sponges, are covered and shown to be non-ancestral to the Cambrian Biota before just throwing these names out as if they explain Cambrian Explosion? If you don't want to, or can't afford to, buy it, , Dr. Paul Giem has done a chapter by chapter 'cliff notes' video series on the book here: Darwin's Doubt - Paul Giem - video playlist http://www.youtube.com/playlist?list=PLHDSWJBW3DNUaMy2xdaup5ROw3u0_mK8t The mysterious Ediacara biota, which also appeared abruptly before, or maybe alongside, the Sponges and Jellyfish, in the pre-Cambrian fossil record, largely disappeared from the fossil record a few million years before the Cambrian Explosion and thus are not seen to be viable as precursors to the Cambrian Explosion. Plant or Animal? Mysterious Fossils Defy Classification Excerpt: "Animals in the Ediacaran Period are almost universally bizarre, and it is very difficult to place them in any modern animal phyla," Xiao told LiveScience. http://www.livescience.com/12883-plant-animal-mysterious-fossils-defy-classification.html The Avalon Explosion: Excerpt: Ediacara fossils [575 to 542 million years ago (Ma)] represent Earth's oldest known complex macroscopic life forms,,, A comprehensive quantitative analysis of these fossils indicates that the oldest Ediacara assemblage—the Avalon assemblage (575 to 565 Ma)—already encompassed the full range of Ediacara morphospace. http://www.sciencemag.org/cgi/content/abstract/319/5859/81 Ediacaran embryos in retrospect - David Tyler - January 28, 2013 Excerpt: "there is currently no convincing evidence for advanced animals with bilateral symmetry in the Doushantuo biota". This particular quest for animals preceding the Cambrian Explosion has drawn a blank. Needless to say, Darwin's dilemma remains in full force. http://www.arn.org/blogs/index.php/literature/2013/01/28/ediacaran_embryos_in_retrospect Interestingly, 'soft-bodied' Jellyfish may have appeared in the fossil record a few ten million years before the Cambrian Explosion, and have remained virtually unchanged since they first appeared in the fossil record. Ancient fossilized Cambrian jellies compared to modern jellies – pictures http://qvcproject.blogspot.com/2012/08/the-joys-of-jellies_2.html Zach, I'll rest my case here, since I have much better things to do today than watch you chase your tail around in a circle. bornagain77

bornagain77: the trick is premised on “including as part of the Cambrian explosion (a) the origin of the Ediacaran organisms in the late Precambrian (which no serious scientist considers to be ancestral to the Cambrian animals) Bilaterian were extant in the Ediacaran. Zachriel

Darwinists continually try to down play the brevity of the main pulse of the Cambrian, refusing to be honest to just how problematic the Cambrian explosion actually is for Darwinism Undead: The Myth of the 80-Million-Year Cambrian Explosion - November 13, 2013 Excerpt: the trick is premised on "including as part of the Cambrian explosion (a) the origin of the Ediacaran organisms in the late Precambrian (which no serious scientist considers to be ancestral to the Cambrian animals), and (b) the small shelly fossils at the base of the Cambrian and (c) the main pulse of morphological innovation in the early Cambrian, and (d) subsequent diversification events right up until the end of the Cambrian period.",,, - Meyer notes that Marshall himself elsewhere excludes the precious small shellies.,,,- http://www.evolutionnews.org/2013/11/undead_the_myth079081.html A Graduate Student (Nick Matzke) Writes - David Berlinski July 9, 2013 Excerpt: Representatives of twenty-three of the roughly twenty-seven fossilized animal phyla, and the roughly thirty-six animal phyla overall, are present in the Cambrian fossil record. Twenty of these twenty-three major groups make their appearance with no discernible ancestral forms in either earlier Cambrian or Precambrian strata. Representatives of the remaining three or so animal phyla originate in the late Precambrian, but they do so as abruptly as the animals that appeared first in Cambrian. Moreover, these late Precambrian animals lack clear affinities with the representatives of the twenty or so phyla that first appear in the Cambrian. http://www.evolutionnews.org/2013/07/a_graduate_stud074221.html Dr. Stephen Meyer: Darwin's Dilemma - The Significance of Sponge Embryos - video http://www.youtube.com/watch?v=JPs8E7y0ySs What Types of Evolution Does the Cambrian Explosion Challenge? (Universal Common Descent & Gradual Change)– Stephen Meyer - video https://www.youtube.com/watch?v=AaF7t5wRFtA Moreover, Darwinists just assume the Cambrian explosion happened by unguided processes but have no detailed account how it is remotely plausible to happen by unguided processes: When Nature Resists: Explaining the Origin of the Animal Phyla - Paul Nelson - April 5, 2013 Excerpt: ,,,lately, I've run across something related to ontogenetic depth that is, well, mind-blowing. Since 1859, the origin of not a single bilaterian phylum (animal body plan) has been explained in a step-by-step (neo-Darwinian) fashion, where random mutation and natural selection were, as textbooks assert, the primary causal mechanisms. Take your pick of the phyla: Mollusca, Brachiopoda, Chordata, Arthropoda, you name it -- and go looking in the scientific literature for the incremental pathway, via mutation and selection, showing how that body plan was assembled from its putative bilaterian Last Common Ancestor. You'll be looking a long time.,,, http://www.evolutionnews.org/2013/04/paul_nelson_day070871.html Response to Critics - Meyer - Marshall - Part 1 https://www.youtube.com/watch?v=zqYUoRVswRY Response to Critics - Meyer - Marshall - Part 2 https://www.youtube.com/watch?v=Cg8Mhn2EKvQ Response to Critics - Meyer - Marshall - Part 3 https://www.youtube.com/watch?v=fR_Agl41TbE Moreover, there are 'yawning chasms' in the 'morphological space' between the phyla which suddenly appeared in the Cambrian Explosion,,, "Over the past 150 years or so, paleontologists have found many representatives of the phyla that were well-known in Darwin’s time (by analogy, the equivalent of the three primary colors) and a few completely new forms altogether (by analogy, some other distinct colors such as green and orange, perhaps). And, of course, within these phyla, there is a great deal of variety. Nevertheless, the analogy holds at least insofar as the differences in form between any member of one phylum and any member of another phylum are vast, and paleontologists have utterly failed to find forms that would fill these yawning chasms in what biotechnologists call “morphological space.” In other words, they have failed to find the paleolontogical equivalent of the numerous finely graded intermediate colors (Oedleton blue, dusty rose, gun barrel gray, magenta, etc.) that interior designers covet. Instead, extensive sampling of the fossil record has confirmed a strikingly discontinuous pattern in which representatives of the major phyla stand in stark isolation from members of other phyla, without intermediate forms filling the intervening morphological space." Stephen Meyer - Darwin’s Doubt (p. 70) Moreover, this top down pattern in the fossil record, which is the complete opposite pattern as Darwin predicted for the fossil record, is not only found in the Cambrian Explosion, but this 'top down', disparity preceding diversity, pattern is found in the fossil record subsequent to the Cambrian explosion as well. Scientific study turns understanding about evolution on its head – July 30, 2013 Excerpt: evolutionary biologists,,, looked at nearly one hundred fossil groups to test the notion that it takes groups of animals many millions of years to reach their maximum diversity of form. Contrary to popular belief, not all animal groups continued to evolve fundamentally new morphologies through time. The majority actually achieved their greatest diversity of form (disparity) relatively early in their histories. ,,,Dr Matthew Wills said: “This pattern, known as ‘early high disparity’, turns the traditional V-shaped cone model of evolution on its head. What is equally surprising in our findings is that groups of animals are likely to show early-high disparity regardless of when they originated over the last half a billion years. This isn’t a phenomenon particularly associated with the first radiation of animals (in the Cambrian Explosion), or periods in the immediate wake of mass extinctions.”,,, Author Martin Hughes, continued: “Our work implies that there must be constraints on the range of forms within animal groups, and that these limits are often hit relatively early on. Co-author Dr Sylvain Gerber, added: “A key question now is what prevents groups from generating fundamentally new forms later on in their evolution.,,, http://phys.org/news/2013-07-scientific-evolution.html “In virtually all cases a new taxon appears for the first time in the fossil record with most definitive features already present, and practically no known stem-group forms.” TS Kemp - Fossils and Evolution,– Curator of Zoological Collections, Oxford University, Oxford Uni Press, p246, 1999 “What is missing are the many intermediate forms hypothesized by Darwin, and the continual divergence of major lineages into the morphospace between distinct adaptive types.” Robert L Carroll (born 1938) – vertebrate paleontologist who specialises in Paleozoic and Mesozoic amphibians bornagain77

Finding that starfish where not echinodrems would indeed be a huge surprise. But there is no evidence for such a proposition, and huge amount of evidence they are echinoderms, so I think we can disregard that. The rest of your comments seem to have very little to do with ID at all, just (not very well informed) phylogenetic thinking. I can't see how a radial adult arising holding on to a linear arrangement of hox genes is more or less surprising under evolution or ID. wd400

wd400: The tetrapods evolved from the lobe-finned fishes which date back to 395 mya. The starfish date back to 450 mya. Looking at their fossil remains, it would appear to be a body-plan formed by an iteration of the basic chordate plan. Unusual. But, since we're dealing with the basic chordate plan, the linear array of Hox genes might not be such a surprise after all. However, this also might mean that its true phylogeny might lie outside of the echinoderm lineage. We'll leave that to the experts. But this rearrangement of the tree of life would be, I think you'd have to admit, a "surprise." And again, to imagine using a basic plan five times over is not hard from the ID perspective. PaV

bornagain77 (quoting Wells): “The Cambrian Explosion was so short that it is below the resolution of the fossil record. It could have happened overnight. So we don’t know the duration of the Cambrian Explosion. We just know that it was very, very, fast.” Well, that's simply not the case. The Cambrian is divided into ten stages, with distinctive fossils in each stage. ETA: Furthermore, there is evidence in the Precambrian of metazoans. Zachriel

as to: "No one doubts that echinoderms descend from a bilaterally symmetrical animal" Seeing as echinoderms suddenly appeared in the Cambrian Explosion along with the other 20 or so phyla I certainly think there is more than enough room for someone, even wd400 himself, to 'doubt': "The first universally accepted echinoderms appear in the Lower Cambrian period,",,, It is hypothesized that the ancestor of all echinoderms was a simple, motile, bilaterally symmetrical animal http://en.wikipedia.org/wiki/Echinoderm 'hypothesis' is far from 'no one doubts' and the Cambrian Explosion is certainly NOT comforting for Darwinists! "The Cambrian Explosion was so short that it is below the resolution of the fossil record. It could have happened overnight. So we don't know the duration of the Cambrian Explosion. We just know that it was very, very, fast." Jonathan Wells - Darwin's Dilemma Quote bornagain77

It’s really good to have some hard data showing that some echinoderms exhibit some oddities that are not representative of all echinoderms. Mung: Amen to that! Finally, some hard proof that echinoderms evolved and weren’t just ‘poofed’ into existence.

Evolution predicts that observations will not line up with the theory. It's really good that we have some hard data proving that evolution was correct. Silver Asiatic

No one doubts that echinoderms descend from a bilaterally symmetrical animal. They are even bilaterally symmetric as larvae (perhaps the one thing I know about their developement). You'd have to be nuts to think they descended from a tetrapod, since they pre-date us by several hundred million years. So, no, I don't think ID is getting us anywhere here. wd400

wd400: Let me begin with this quote of RodW:

The fossil record shows that echinoderms used to be bilaterally symmetrical ( like most other organisms) and the common ancestor of echinoderms and chordates had bilateral symmetry (which requires a linear hox cluster) so they must have originally had their hox genes in a cluster. I

As I reflected on what the study discovered, and before RodW posted, here's how I began to think (BTW, this is how 'designers' think): Think of the tetrapod body-plan. Then think of a stick-man representation of a tetrapod: two lines verging from a center line, with two lines verging from the top of the center line, and then the 'head.' Well, this gives you 5 'lines.' So, the starfish could be an example of a tetrapod that has now changed its body-plan. But this would mean that the starfish would have descended from a tetrapod, or bilaterian, form. IOW, move the two 'arms' down from the top of the center line to the point where the two 'legs' meet the center line. Then move the 'head' down to the center of all of these intersections of lines. You have a starfish. So, you see, from an ID perspective, I judged that the fossil record should show that the starfish was descended from some bilaterian/tetrapod form, which is not what you would expect. This is what RodW explains above. I had to wait, however, to make sure that the Hox genes were, in fact, in a linear order for all of this to make sense given the assumption I've made. And, so, we have RodW's answer:

Yes they are in a linear order on the chromosomes.

Now take this "radial" pattern, and form a cylinder (i.e., layer upon layer), and, basically, you have echinoderms. It is possible that I have just explained the author's surprise. Am I wrong, or are Darwinists surprised, while IDists move off in the right direction? So, there's your answer. PaV

Whether or not starfish use the same hox gene order as vertebrates seems equally surprising or unsurprising under ID or evolution.

Yep. Entirely unremarkable. From the OP:

It’s really good to have some hard data showing that some echinoderms exhibit some oddities that are not representative of all echinoderms.

Amen to that! Finally, some hard proof that echinoderms evolved and weren't just 'poofed' into existence. From the OP:

Thus, we were surprised to see chordate-like Hox cluster organization in starfish, which have a radial body plan.

Starfish are lower on the tree of life than we originally thought. It's almost like finding a rabbit in the Cambrian. Now all we need to cap this off is a good just-so story! Anyone? Mung

I'm firmly in the ID camp, but if evolutionary theory puts starfish as members of a sister group to chordates then I have to agree with wd400: It wouldn't be a case of convergent evolution. Whether or not starfish use the same hox gene order as vertebrates seems equally surprising or unsurprising under ID or evolution. JoeCoder

wd400, I am not one of those folks who thinks ID ought to explain everything. For me, ID is quite limited in it's explanatory scope. Most of the objections to ID I see just make me yawn. I guess you could call me an ID minimalist. But I think I'm at least consistent because I am much the same the same way about evolutionary theory. It assumes too much and demonstrates too little in spite of it's grandiose claims. In the vast majority of cases, we just don't know enough to be certain. I would probably feel more at home over at The Skeptical Zone, but they aren't really skeptics over there. :) Mung

Pav, Yes they are in a linear order on the chromosomes. If you do a google search on 'hox cluster' you'll see a wiki entry for 'hox gene' with a pic...and the google images hit will have a bunch of pics of the clusters in various species. Vertebrates have 4 cluster ( I think some fish might have more) and Drosophila has one which has split RodW

wd400: To answer your question, I need some more information from RodW. PaV

RodW: Thanks for the detailed information. When you speak of a "cluster," are you talking about a "cluster" that is in "linear" order? When I think of a cluster, a think of a kind of 'rounded' group of things. PaV

News and all, The results are surprising because in chordates, flies, worms and many other organisms the Hox genes are arrayed in a linear fashion with genes at one end specifying the head and the genes at the other specifying the tail. The genes are coregulated and so they need to be together in order. Echinoderms have radial symmetry so they dont need to have the hox genes in a cluster, although they'd still need them. The paper says that most echinoderms dont have them in a cluster but starfish do have them in a cluster. The fossil record shows that echinoderms used to be bilaterally symmetrical ( like most other organisms) and the common ancestor of echinoderms and chordates had bilateral symmetry (which requires a linear hox cluster) so they must have originally had their hox genes in a cluster. In most lineages the cluster has broken up. Its "surprising" that it hasnt in starfish. There must be some unique reason why its not been broken up in starfish- maybe a new function or contraint..but if the contraints arent too strong there maybe other starfish where its partially broken up RodW

I don't know how else I can say this. I know nothing about how development works in echinoderms, so I have no way of knowing whether this is suprising in far as development. But I'll ask you the same question: does this result surprise you given your belief in ID? wd400

Here's what the author said:

“Thus, we were surprised to see chordate-like Hox cluster organization in starfish, which have a radial body plan.”

wd400, haven't you oversimplified things by saying, "the result is that some echinoderms have a trait in common with hemichordates and chordates, which is the opposite of surprising." PaV

And how surprising is that finding to an IDer, Mung? wd400

Equally unsurprising is the result that some echinoderms have a trait not in common with hemichordates and chordates. Isn't evolutionary theory wonderful! Mung

News, you seem have mistaken "convergenceis everywhere" with "people keep on publishing press releases when they find a case of convergent evolution". In any case, to answer this one all you had to know was some intro to biology about how animals related to each other. As to the surprise. I don't know anything about development in echinoderms, so I had no expectation. Without that background, the result is that some echinoderms have a trait in common with hemichordates and chordates, which is the opposite of surprising. wd400

Did the study "surprise" you? PaV

Thanks for answering the question, wd400. So this one is common ancestry rather than convergent evolution? Shows how things have changed, that one must now ask (convergence is everywhere). One day, the News desker will be wondering if it is HGT instead (with some reason). And then next, “Thus, we were surprised to see chordate-like Hox cluster organization in starfish, which have a radial body plan.” So WHY were they surprised? News

Is convergent evolution welcome to evolutionary biology? I say its not and is a excuse to explain away unlikely common designs in unrelated creatures with mutations being selected on. They mind a few. Yet convergence everywhere is not desired by evolutionists. It is by ideas of common design. The better the investigation of nature the more nature looks designed. Like answers for like needs in a biology that seeks the simple path. Robert Byers

I don't know anything about development in echinoderms, but I do know what "convergent" means... wd400

wd400: Here's what they say:

“For example, anterior Hox genes are expressed in regions that are closer to the head of an embryo, and are expressed sooner during development, versus the posterior Hox genes,” explained Baughman. “Thus, we were surprised to see chordate-like Hox cluster organization in starfish, which have a radial body plan.”

They're surprised. Why aren't you? PaV

You misspelled Chordettes. Chordette Sister Group Mung

Why convergent? Echinoderms are part of the sister group to chordates. wd400