Skip to comments.Xenacoelomorpha – a new phylum in the animal kingdom
Posted on 02/16/2011 8:42:51 AM PST by decimon
Scientists reorganise the animal phylogenetic tree
An international team of scientists including Albert Poustka from the Max Planck Institute for Molecular Genetics in Berlin has discovered that Xenoturbellida and the acoelomorph worms, both simple marine worms, are more closely related to complex organisms like humans and sea urchins than was previously assumed. As a result they have made a major revision to the phylogenetic history of animals. Up to now, the acoelomate worms were viewed as the crucial link between simple animals like sponges and jellyfish and more complex organisms. It has now emerged that these animals did not always have as simple a structure as they do today.
The genus Xenoturbella lives off the coast of Scandinavia, Scotland and Iceland. It shares a simple body structure with the acoelomorph worms: these organisms, which reach a maximum size of just a few millimetres, have no through gut, no gill slits and no body cavity (Greek: coelom = cavity). Many members of both groups live on the ocean floor and feed on organic particles in the sediment. Some species live parasitic, e.g. in the intestines of sea cucumbers.
The animal kingdom is divided into different evolutionary lines. These include, among others, the protostomes (mouth first) and deuterostomes (second mouth). In the protostomes, the mouth that develops at the beginning of embryonic development becomes the organisms actual mouth, whereas, in the deuterostomes, it becomes the anus and the mouth develops at a later stage. Three deuterostome phyla were known up to now: the Chordates (e.g. vertebrates), the Echinoderms (sea urchins, starfish, sea cucumbers) and the Hemichordates (e.g. acorn worm). Our research shows that Xenoturbellida and Acoelomorpha together form the fourth phylum which we have called Xenacoelomorpha, explains Albert Poustka from the Planck Institute for Molecular Genetics in Berlin.
(Excerpt) Read more at mpg.de ...
Worm outta this ping.
Ib4bf (Bush’s fault).
Dang it. First they take Pluto away and then they tell us Triceratops isn’t a separate species and now this. I think they’re only doing it to sell textbooks. (Walks off, muttering darkly...)
These would be the democrats of the worm world.
Ping to a similarly named creature.
Don’t forget the “They Named the Phyllum a Cool, Cool Thing” Ping List
An entire phylum for two species? Or am I reading this wrong?
Filling the phylum, one worm at a time.
I guess they figure that more critters will be found to belong to this phylum
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The best illustration of how stupid evolutionism really is involves trying to become some totally new animal with new organs, a new basic plan for existence, and new requirements for integration between both old and new organs.
Take flying birds for example; suppose you aren't one, and you want to become one. You'll need a baker's dozen highly specialized systems, including wings, flight feathers, a system for pivoting flight feathers so that they open on up strokes and close on down strokes, a specialized light bone structure, specialized flow-through lungs and a high efficiency heart, a specialized tail, specialized general balance parameters, a beak (since you won't have hands any more...) etc. etc. etc.
For starters, every one of these things would be antifunctional until the day on which the whole thing came together, so that the chances of evolving any of these things by any process resembling evolution (mutations plus selection) would amount to an infinitessimal, i.e. one divided by some gigantic number.
In probability theory, to compute the probability of two things happening at once, you multiply the probabilities together. That says that the likelihood of all these things ever happening at once (which is what you'd need), best case, is ten or twelve such infinitessimals multiplied together, i.e. a tenth or twelth-order infinitessimal. The whole history of the universe isn't long enough for that to happen once.
All of that was the best case. For the pieces of being a flying bird to evolve piecemeal would be much harder. In real life, natural selection could not plausibly select for hoped-for functionality, which is what would be required in order to evolve flight feathers on something which could not fly apriori. In real life, all you'd ever get would some sort of a random walk around some starting point, rather than the unidircetional march towards a future requirement which evolution requires.
And the real killer, i.e. the thing which simply kills evolutionism dead, is the following consideration: In real life, assuming you were to somehow miraculously evolve the first feature you'd need to become a flying bird, then by the time another 10,000 generations rolled around and you evolved the second such reature, the first, having been disfunctional/antifunctional all the while, would have DE-EVOLVED and either disappeared altogether or become vestigial.
Now, it would be miraculous if, given all the above, some new kind of complex creature with new organs and a new basic plan for life had ever evolved ONCE.
Evolutionism, however (the Theory of Evolution) requires that this has happened countless billions of times, i.e. an essentially infinite number of absolutely zero probability events.
And, if you were starting to think that nothing could possibly be any stupider than believing in evolution despite all of the above (i.e. that the basic stupidity of evolutionism starting from 1980 or thereabouts could not possibly be improved upon), think again. Because there is zero evidence in the fossil record to support any sort of a theory involving macroevolution, and because the original conceptions of evolution are flatly refuted by developments in population genetics since the 1950's, the latest incarnation of this theory, Steve Gould and Niles Eldredge's "Punctuated Equilibrium or punc-eek" attempts to claim that these wholesale violations of probabilistic laws all occurred so suddenly as to never leave evidence in the fossil record, and that they all occurred amongst tiny groups of animals living in "peripheral" areas. That says that some velocirapter who wanted to be a bird got together with fifty of his friends and said:
Guys, we need flight feathers, and wings, and specialized bones, hearts, lungs, and tails, and we need em NOW; not two years from now. Everybody ready, all together now:
You could devise a new religion by taking the single stupidest doctrine from each of the existing religions, and it would not be as stupid as THAT.
But it gets even stupider.
Again, the original Darwinian vision of gradualistic evolution is flatly refuted by the fossil record (Darwinian evolution demanded that the vast bulk of ALL fossils be intermediates) and by the findings of population genetics, particularly the Haldane dilemma and the impossible time requirements for spreading genetic changes through any sizeable herd of animals.
Consider what Gould and other punk-eekers are saying. Punc-eek amounts to a claim that all meaningful evolutionary change takes place in peripheral areas, amongst tiny groups of animals which develop some genetic advantage, and then move out and overwhelm, outcompete, and replace the larger herds. They are claiming that this eliminates the need to spread genetic change through any sizeable herd of animals and, at the same time, is why we never find intermediate fossils (since there are never enough of these CHANGELINGS to leave fossil evidence).
Obvious problems with punctuated equilibria include, minimally:
1. It is a pure pseudoscience seeking to explain and actually be proved by a lack of evidence rather than by evidence (all the missing intermediate fossils). Similarly, Cotton Mather claimed that the fact that nobody had ever seen or heard a witch was proof they were there (if you could SEE them, they wouldn't BE witches...) This kind of logic is less inhibiting than the logic they used to teach in American schools.
2. PE amounts to a claim that inbreeding is the most major source of genetic advancement in the world. Apparently Steve Gould never saw Deliverance...
3. PE requires these tiny peripheral groups to conquer vastly larger groups of animals millions if not billions of times, which is like requiring Custer to win at the little Big Horn every day, for millions of years.
4. PE requires an eternal victory of animals specifically adapted to localized and parochial conditions over animals which are globally adapted, which never happens in real life.
5. For any number of reasons, you need a minimal population of any animal to be viable. This is before the tiny group even gets started in overwhelming the vast herds. A number of American species such as the heath hen became non-viable when their numbers were reduced to a few thousand; at that point, any stroke of bad luck at all, a hard winter, a skewed sex ratio in one generation, a disease of some sort, and it's all over. The heath hen was fine as long as it was spread out over the East coast of the U.S. The point at which it got penned into one of these "peripheral" areas which Gould and Eldredge see as the salvation for evolutionism, it was all over.
The sort of things noted in items 3 and 5 are generally referred to as the "gambler's problem", in this case, the problem facing the tiny group of "peripheral" animals being similar to that facing a gambler trying to beat the house in blackjack or roulette; the house could lose many hands of cards or rolls of the dice without flinching, and the globally-adapted species spread out over a continent could withstand just about anything short of a continental-scale catastrophe without going extinct, while two or three bad rolls of the dice will bankrupt the gambler, and any combination of two or three strokes of bad luck will wipe out the "peripheral" species. Gould's basic method of handling this problem is to ignore it.
And there's one other thing which should be obvious to anybody attempting to read through Gould and Eldridge's BS:
They are claiming that at certain times, amongst tiny groups of animals living in peripheral areas, a "speciation event(TM)" happens, and THEN the rest of it takes place. In other words, they are saying:
ASSUMING that Abracadabra-Shazaam(TM) happens, then the rest of the business proceeds as we have described in our scholarly discourse above!
Again, Gould and Eldridge require that the Abracadabra-Shazaam(TM) happen not just once, but countless billions of times, i.e. at least once for every kind of complex creature which has ever walked the Earth. They do not specify whether this amounts to the same Abracadabra-Shazaam each time, or a different kind of Abracadabra-Shazaam for each creature.
New invertebrate phylum in the Kingdom! There will be toga parties!
It boils down to are you are splitter or a lumper. You must make the decision.
There are innumerable examples amongst living species, the fossil record, DNA analysis and even embryo development of "intermediate" stages, showing how evolution can proceed one-step-at-a-time, over many millions of generations, to eventually produce the diversities we see today.
Wendy1946: "In real life, all you'd ever get would some sort of a random walk around some starting point, rather than the unidircetional march towards a future requirement which evolution requires. "
Every tiny step on the path, for example, from reptile to bird stands alone as the result of genetic mutation and natural selection.
Sure, some have claimed that a particular evolutionary step is impossible, but no one has ever proved that scientifically.
Wendy1946: "...the first, having been disfunctional/antifunctional all the while, would have DE-EVOLVED and either disappeared altogether or become vestigial."
In DNA terms, vestigial features are never fully lost.
If over time, some "vestigial" function were to begin increasing survivability in a species, then that function would soon be selected for, along with any enhancements which further increase survivability.
In other words, in time it would no longer be "vestigial."
Wendy1946: "Evolutionism, however (the Theory of Evolution) requires that this has happened countless billions of times, i.e. an essentially infinite number of absolutely zero probability events."
Note the sequence and time periods:
A key point to notice here is that major changes take very, very long times.
Relatively minor changes happen more quickly.
Wendy1946: "But it gets even stupider."
Referring to your own arguments, presumably.
A good place for me to stop.
When a theory reaches the point of being defensible only by lying, you should drop it.
And yet you continue to argue against the truth.
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