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Old 04-20-2002, 06:01 AM   #71
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Do you believe that Archaeopteryx is a transitional?

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yes. Because it has features found in both reptiles and birds. Although it's classified as a perching bird, several pronounced features are very similar to features found in reptiles. It's classifiaction as a bird doesn't make it non-transitional.
Oolon, I am interested that you do not point this out - or maybe you didn't see it.

The Archaeopteryx puzzled many zoologists cause the flying reptile was distinctling reptile but the feathers were modern birds' feathers.

But it was the leading Cambridge scientist, Fred Hoyle who discovered that the fossil was a fraud.
He examined the fossil under the mircroscope and saw that the birds feathers had been stuck on with glue. - It is a fraud - not a link.

The fossil record doesn't support the suggestion that feathers developed from reptile scales...nor from anything else for that matter.
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Old 04-20-2002, 06:22 AM   #72
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Actually it seems that the feathers were dispuited because of the imprints on them, not because they were glued. Though the glue part might be the case - I haven't read what Holye wrote.
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Old 04-20-2002, 06:30 AM   #73
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Here are some other things to think about;

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“Apart from the proportions of its wings, the skeleton of Archaeopteryx is strikingly similar to that of a small, lightly built, running dinosaur, such as the coelurosaur Compsognathus.” Dougal Dixon et al., The Macmillan Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals (New York: Macmillan Publishing Company, 1988), p. 172.
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. “Phylogenetic analysis of stem-group birds reveals that Archaeopteryx is no more closely related to modern birds than are several types of theropod dinosaurs, including tyrannosaurids and ornithomimids. Archaeopteryx is not an ancestral bird, nor is it an ‘ideal intermediate’ between reptiles and birds. There are no derived characters uniquely shared by Archaeopteryx and modern birds alone; consequently there is little justification for continuing to classify Archaeopteryx as a bird.” R. A. Thulborn, “The Avian Relationships of Archaeopteryx and the Origin of Birds,” Zoological Journal of the Linnean Society, Vol. 82, 1984, p. 119.
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Two milligram-size samples of the fossil material were tested, one from a “feather” region and a control sample from a nonfeathered region. The British Museum “contends that the amorphous nature of the feathered material is an artifact explainable by preservatives that they have put on the fossil.” [Lee M. Spetner, “Discussion,” Proceedings of the Second International Conference on Creationism (Pittsburgh, Pennsylvania: Creation Science Fellowship, 1990), p. 289.] If this excuse were correct, why were no “preservatives” found on the control specimen? Control specimens are tested for precisely this purpose—to dispel unique, last-minute excuses. The British Museum has refused further testing, a shocking position for a scientific organization, and one which raises suspicions to the breaking point.
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. “... these specimens [of Archaeopteryx] are not particularly like modern birds at all. If feather impressions had not been preserved in the London and Berlin specimens, they [the other specimens] never would have been identified as birds. Instead, they would unquestionably have been labeled as coelurosaurian dinosaurs [such as Compsognathus]. Notice that the last three specimens to be recognized [as Archaeopteryx] were all misidentified at first, and the Eichstätt specimen for 20 years was thought to be a small specimen of the dinosaur Compsognathus.” John H. Ostrom, “The Origin of Birds,” Annual Review of Earth and Planetary Sciences, Vol. 3, 1975, p. 61.
Those are some other things to think about.
- I mean why would the British museum refuse further testing? Raises the suppisions a bit doesn't it.
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Old 04-20-2002, 10:52 AM   #74
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Originally posted by davidH:
<strong>

Oolon, I am interested that you do not point this out - or maybe you didn't see it. </strong>
Why me? I'm not the only one here y'know. No, I saw it, but it's the weekend here in the UK, and weekend means I'm at home not at work, and that means I can't follow up everything. I have every confidence in our 'team', and do not feel the need to respond to every damn thing (though it may sometimes look like that )

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<strong>The Archaeopteryx puzzled many zoologists cause the flying reptile was distinctling reptile but the feathers were modern birds' feathers.</strong>
It didn't puzzle all that many, since zoologists are (by default) 'evolutionists', and evolution predicts just such things as Archie.

Quote:
<strong>But it was the leading Cambridge scientist, Fred Hoyle who discovered that the fossil was a fraud.
He examined the fossil under the mircroscope and saw that the birds feathers had been stuck on with glue. - It is a fraud - not a link.</strong>
BWAHAHAHA! ROTFLMFAO!

1. Hoyle and Wickramasinghe were W.R.O.N.G. Hoyle was a great astronomer, not palaeontologist, and his attacks on evolution were linked it seems to his desperation to keep his 'steady state' universe theory going. More fool him. Alan Charig at the Natural History Museum performed the most microscopic crystalline analyses on the NHM's Archie specimen, and the feathers were all of a part with the bones. It is NOT a forgery.

2. The NHM's specimen is not the only one! There are at least SEVEN specimens: Haarlem 1855, London 1861; Berlin 1877, Eichstatt 1951, Maxberg 1956, Solnhofen 1987 and Solnhofen Aktien-Verein 1992, all from the upper Solnhofen lithographic limestone (late Jurassic) in Bavaria. Creationists are propopsing a series of hoaxes spread over 130 years!

3. This is old news David, hence my mirth. Once again, you prefer the cretinist lie to the truth. You didn't wonder why Archaeopteryx is still used in textbooks if it is false, you simply went with the liars whose answer you prefer. More fool you, allowing these guys to have you make a tit of yourself in public. Again.

There's loads more about Archie here: <a href="http://talkorigins.org/faqs/archaeopteryx.html" target="_blank">http://talkorigins.org/faqs/archaeopteryx.html</a>

TTFN, Oolon
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Old 04-20-2002, 03:10 PM   #75
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Thanatos asked those of us here assembled to "Read these and then tell me that DNA evidence is consistent with evolutionary theory." I can do that, to some small extent:

"Genome Data Shake Tree of Life" E Pennisi, Science, Volume 280, Number 5364, Issue of 1 May 1998, pp. 672-674. (A staff background article, not a peer-reviewed piece.)
From the article:

Quote:
For one, because genes don't evolve at the same rate or in the same way, the evolutionary history inferred from one gene--say for rRNA--may be different from what another gene appears to show. "Before, people tended to equate rRNA trees with the [life history] tree of the organism," says John Reeve, a microbiologist at Ohio State University in Columbus. "From the whole genomes, you very quickly come across [genes] that don't agree with the rRNA tree."

Even more perplexing, the newly unveiled genomes often contain a mix of DNAs, some seeming to come from the archaea and others from bacteria. "Features of both bacteria and archaea are turning up in eukaryotes, and to a surprising degree," says Russell Doolittle, a molecular evolutionist at the University of California, San Diego.

Many evolutionary biologists are coming to believe that these mosaics arose because genes hopped from branch to branch as early organisms either stole genes from their food or swapped DNA with their neighbors, even distantly related ones. The genetic oddballs may simply mean that the branches of the tree of life intertwine, but that the basic shape is sound. But if the gene swapping was extensive enough, the true branching pattern may be quite difficult to discern. Worse, the tree's "base" may turn out to be indecipherable: a network of branches that merge and split and merge again before sprouting the modern kingdoms. It may be, Woese concedes, that "you can't make sense of these phylogenies because of all the [gene] swapping back and forth."
and
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But the tree Feldman derived from the gene for the tryptophan synthesis enzyme implies a more insidious problem: the possibility of widespread gene swapping among organisms, which could make arriving at a consensus tree quite difficult. Few researchers think Aquifex is kissing cousin to archaea, in spite of the similarity of their genes for this enzyme. The enzyme might be a relic from the ancestor common to both kingdoms, which has evolved unexpectedly slowly since then. But more likely, at some point, Aquifex took on the archaeal gene, substituting it for its own version, a process called lateral transfer.

Gene swapping
Not too long ago, attributing an unusual result to lateral transfer would have raised quite a few eyebrows. For years molecular evolutionists tended to use this idea to excuse irregularities in their attempts to construct phylogenetic trees, when actually their methods were at fault. But the microbial genomes have made the idea respectable.

In one case last year, for instance, W. Ford Doolittle, an evolutionary molecular biologist with the Canadian Institute for Advanced Research in Halifax, Nova Scotia, scanned the genome of an archaeon called Archaeoglobus fulgidus, newly sequenced by The Institute for Genomic Research (TIGR) in Rockville, Maryland, with a computer program that searches new genomes for resemblances to genes in existing databases. The scan turned up an enzyme called a reductase that was much more like the reductases seen in bacteria than like comparable enzymes in other archaea and eukaryotes--supposedly the closer relatives of A. fulgidus.
and:
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Although some modern bacteria are quite adept at taking up new genes--many pathogens develop antibiotic resistance this way--the successful incorporation of genes from food bacteria into eukaryotic genomes would be accidental and infrequent. But "we've got hundreds of millions of years for it to happen," Ford Doolittle points out. Also, these genetic morsels are consumed with each meal, so that an incoming gene can have many opportunities to get into the genome and replace its native counterpart. In contrast, once a native gene happens to get removed from the host's genome, "it's lost forever," he adds. Over evolutionary time, these processes would favor the loss of native genes and their replacement with borrowed ones.

Woese thinks gene swapping was rampant even among life's earliest organisms. In his view, the organisms that lived before archaea, eukarya, and bacteria went their separate ways lived communally. "It was more like a consortium," Woese says of this very early world. The ability to make use of a neighbor's genes would have proved an important advantage, he asserts.

Members of this consortium may even have had different genetic codes. But the organisms that outlasted the rest would have been those that could make use of their neighbor's genes to adapt to changing conditions, says Woese. Over time, this advantage "ensured that the [DNA] code was universal," he says, because those not able to read DNA-based genes could not survive as well as those organisms using DNA.
That all sounds to me like a good set of interesting problems to grow a new crop of grad students - it is hardly any surprise to me that life is messier than we would like it to be - most of our lives damn sure are.

Next, "The Abominable Mystery", William L. Crepet, Science, Volume 282, Number 5394, Issue of 27 Nov 1998, pp. 1653-1654. (A commentary, not peer-reviewed, by a practicing scientist in the field.)
Quote:
The report by Sun et al. (1) on page 1692 of this issue describes the first plausible fossil evidence of a Jurassic angiosperm (the type of plants that have flowers and fruits). This finding has important implications for one of evolutionary biology's most enduring puzzles: the origin of, and relationships within, the flowering plants--what Charles Darwin called the "abominable mystery."
and, skipping quite a bit,
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This is potentially a big discovery. Although its age and chimeric nature imply that Archaefructus may represent the most "primitive" angiosperm yet discovered, final confirmation of its basal status and its angiospermous nature depend on precise phylogenetic context. Phylogenetic analysis is also necessary to rationalize the conflicting combination of characters now found in opposing models of primitive angiosperms. Can such an analysis be accomplished to everyone's satisfaction with the characters now available in Archaefructus? Probably not, because too many important characters are now missing, especially stamen position and structure, pollen morphology, and leaf and seed structure. However, through my experience in fossil collecting, I have learned that the discovery of a few specimens of a new fossil taxon is seldom a unique event--there will be new specimens of Archaefructus and the kinds of characters critically needed are also the kinds likely to be preserved. Given the potential informative value of this taxon and the recent pace of innovation in studies of angiosperm systematics and paleobotany today, I predict that the great "abominable mystery," with us for over 100 years, will not last another 10.
The article mentions DNA/RNA only in passing; its concern is the fossil record.

I don't see any evidence of "inconsistency." Thanatos, have you read these articles? The titles sounded pretty good for the antievolutionary side, but once you get past them into the text........
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Old 04-20-2002, 03:25 PM   #76
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I only had time to read the first several posts, no time to catch up on all 3 pages.

However I am wondering if someone has pointed out the bilogical blueprints for certain "knowledge" or behavior can not only be inherited but also can be ingested. :-)

Don't ask me who or when did the studies, my brain is not an encyclopedia.

However, in my evolutionary biology class we learned about and experiment that was on on single celled organisms.

Apparently a group of single celled organisms or certainly very miniscule organisms were trained to follow a light.

There was another group that could not immediately follow the light as they hadn't been trained or conditioned to follow the light.

The group of organisms that were trained to follow the light were ground up and then fed to the group of organisms that had NOT been trained to follow the light. Upon eating the trained organisms, the untrained organisms immediately were able to follow the light despite never having been trained/conditioned to do so.

I found that fascinating how biology works.

Sorry that I can't remember the details or the sources but it was more than a decade ago that I was learning about these things.

Also, has anyone brought up how celluar phone activity interferes with bird migration???

Pigeon races are now held almost exclusively on weekends when cellular phone activity is at a minimum. This is because too many homing pigeons get lost, confused, and never make it home when they try to do it during the week when cell phone activity is high.

So I would think that one of the main homing, navigation methods in birds is magnetism, however some studies I read about leaned towards multiple navigation devices that birds use and if one thing fails the other kicks in but some are more used and more important than others, some are just back up devices.
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Old 04-20-2002, 03:44 PM   #77
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MDgirl: The "learning through eating" experiment sounds like the work from the 1960's (?) on planaria (flatworms), which I think has been at least partially debunked. Some of the real biologists around here may know more.
Can you give any links on the pigeon/cell phone interference? That sounds interesting.
Oh, a big welcome to II!
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Old 04-21-2002, 02:08 AM   #78
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Godless Dave:
The lungfish. Various varieties of lungfish live in Africa and Australia. They have both lungs and gills, both of which allow it to take in oxygen (the lungs from the air, the gills from water). They evolved from regular fish, who only took in oxygen through their gills. They had an air bladder that was used for controlling ascent and descent in the water. The ancestor of the lungfish had a mutation (or series of mutations) that turned the air bladder into a lung that could breathe in air and pass oxygen to the bloodstream.
Actually, the usual view is that swim bladders had evolved from lungs, but the principle is correct. Note that the simplest lungs are simple pouches in the throat, with more complex lungs getting lots and lots of branching to produce lots and lots of subpouches.

Also, duplicated genes are a good example of how greater complexity can evolve. One copy can stay specialized for its original function, allowing the other to become specialized for some other function. And repeating this process can create a whole family of closely-related genes; several gene families are known and some have been intensively studied, such as the globin and homeobox families.
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Old 04-24-2002, 12:05 PM   #79
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Bumping this up now that Thanatos is back, hoping he'll answer some of our questions, including this one:

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Originally posted by MrDarwin:
<strong>I'm curious to know what makes Thanatos think that the tuatara, and coelacanth, and the frogs of New Zealand haven't changed "for over 200 million years". Care to tell us where you got that info, Thanatos?</strong>
I'm still wondering (1) why Thanatos finds this apparent stasis significant, and (2) why he thinks it's true in the first place?
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