Posted on 04/02/2004 4:25:18 PM PST by PatrickHenry
Arlington, Va.How land-living animals evolved from fish has long been a scientific puzzle. A key missing piece has been knowledge of how the fins of fish transformed into the arms and legs of our ancestors. In this week's issue of the journal Science, paleontologists Neil Shubin and Michael Coates from the University of Chicago and Ted Daeschler from the Academy of Natural Sciences in Philadelphia, describe a remarkable fossil that bridges the gap between fish and amphibian and provides a glimpse of the structure and function changes from fin to limb.
The fossil, a 365-million-year-old arm bone, or humerus, shares features with primitive fish fins but also has characteristics of a true limb bone. Discovered near a highway roadside in north-central Penn., the bone is the earliest of its kind from any limbed animal.
"It has long been understood that the first four-legged creatures on land arose from the lobed-finned fishes in the Devonian Period," said Rich Lane, director of the National Science Foundation's (NSF) geology and paleontology program. "Through this work, we've learned that fish developed the ability to prop their bodies through modification of their fins, leading to the emergence of tetrapod limbs."
NSF, the independent federal agency that supports fundamental research and education across all fields of science and engineering, funded the research.
The bone's structure reveals an animal that had powerful forelimbs, with extensive areas for the attachment of muscles at the shoulder. "The size and extent of these muscles means that the humerus played a significant role in the support and movement of the animal," reported Shubin. "These muscles would have been important in propping the body up and pushing it off of the ground."
Interestingly, modern-day fish have smaller versions of the muscles. According to Coates, "When this humerus is compared to those of closely-related fish, it becomes clear that the ability to prop the body is more ancient than we previously thought. This means that many of the features we thought evolved to allow for life on land originally evolved in fish living in aquatic ecosystems."
The layered rock along the Clinton County, Penn., roadside were deposited by ancient stream systems that flowed during the Devonian Period, about 365 million years ago. Enclosed in the rocks is fossil evidence of an ecosystem teeming with plant and animal life. "We found a number of interesting fossils at the site," reported Daeschler, who uncovered the fossil in 1993. "But the significance of this specimen went unnoticed for several years because only a small portion of the bone was exposed and most of it lay encased in a brick-sized piece of red sandstone."
Not until three years ago, when Fred Mullison, the fossil preparator at the Academy of Natural Sciences, excavated the bone from the rock, did the importance of the new specimen become evident.
The work was also funded by a grant from the National Geographic Society.
I am not a big fan of people who begin with a flawed premise and then try to construct "a very large intellectual edifice based on few facts" to borrow from an earlier quote.
The one that shows.....[snip]
You seem to be confused; my posts deal with topics other than those you asked about.
If the evolutionist view is accurate, the fish darn well better</b have shoulders! Otherwise you don't have a transitional form.
" I think even the lobe-finned fish had a sort of shoulder."
If the evolutionist view is accurate, the fish darn well better have shoulders! Otherwise you don't have a transitional form.
Whic is also ridiculous because there are subtle differences between the same basic proteins when you look from species to species (and mapping out these changes in proteins has been a great tool for evolutionists to use to determine which species descended from which). If a single change in the Hemoglobin molecule would render it useless, how do other species surivive, if they have slightly different forms of Hemoglobin in them?
Here ya go sparky: http://www.scienceagainstevolution.org/v6i10n.htm
Snowflakes are a lower energy form of water, not a higher energy form. They are moving toward equilibrium, not away from it. Ditto for crystals. Hurricanes? They are by definition low-pressure cells. They are chasing equilbrium as well. To say that Hurricanes 'form' is like saying the sun rises. Hurricanes are where heat and energy 'go'. They are not a net increase in energy. It is merely a perspective. Hurricanes lose heat and dissipate energy.
As to the last response. To quote Isaac Asimove (no Creationist there!) "we can see the Second Law all about us. We have to work hard to straighten a room, but left to itself it becomes a mess again very quickly and very easily. Even if we never enter it, it becomes dusty and musty. How difficult to maintain houses, and machinery, and our own bodies in perfect working order; how easy to let them deteriorate. In fact, all we have to do is nothing, and everything deteriorates, collapses, breaks down, wears out, all by itself and that is what the Second Law is all about."
This strikes me as very poorly reasoned. At any rate, it needs some explanation. The forelimb/fins on Eusthenopteron (a step or two earlier than the Pandericthys I mention above) seem to have attached with soft tissue, not a real shoulder bone. So what? It obviously worked. How do you justify imposing an order of appearance which may not be what happened?
Remember what Dawkins said, "Evolution is smarter than you are."
What could possibly be more VAGUE and EXTREME than this "God" I keep hearing about?
Do you claim God is not "extreme?" Because all I hear about is how he's all-powerful, all-knowing, all-loving, master of all life. Even more so than those guys in the Mountain Dew commercials. I mean, he's EXTREME.
And would you claim that "God" isn't vague? I mean, if you can give me an EXACT, NOT-AT-ALL VAGUE description of God that pins Him down exactly, I'd love to hear it.
"The shoulders exhibits (sic--but I'm in no position today to complain about someone else's conjugations) several tetrapod-like features, while the humerus is longer than those found in other lobe-fins. On the other hand, the distal parts of the front fins are unlike those of tetrapods. As would be expected from a fin, there are numerous lepidotrichs (long and thin fin rays). The distal fin also has a plate of fused radial bones instead of the fingers found in tetrapods.
Maybe I'm wrong, maybe fish DO "exhibits" shoulders, hmmm. I wish I had a picture, I don't trust these words of bone-dreamers.
Disorder? Now that happens all on its own. If chaos reigned in the universe, it would be entirely logical to assume no designer.
But then if chaos reigned, you couldn't form the thought for the observation to begin with, so.......
Yeah, maybe it's all a fake. We might really be sitting around a cave somewhere dreaming this. Thanks for the scientific insight.
That being the case, does 1 gram of snowflakes at zero Celsius have more or less entropy than the 1 gram of liquid water at the same temperature?
I don't think you do. Explain it to me, in detail.
I never used the word "design." The word "design" implies a designer, that is why evolutionists avoid the word to describe the structure of living things.
If there are immutable laws of nature, who made/created the laws?
Beats the s--- out of me. I have no clue. I mean I really, really don't know. But what does this have to do with evolution?
Order doesn't just happen.
Yes, it does. Look at crystalline structures that form naturally in the world. They are just collections of atoms/molecules acting according to simple rules of physics/chemistry, but by following those simple rules they end up in ordered shapes. That they are arrayed in an orderly manner does not suggest that some intelligence set them up, or that they decided/desired that shape.
Anthropomorphism is the "Attribution of human motivation, characteristics, or behavior to inanimate objects, animals, or natural phenomena." It's a logical fallacy to assume that all order must come from human-like logic.
"Order without design" is the idea behind this and is in fact the logic behind a lot of libertarian thought.
Disorder? Now that happens all on its own.
No, it doesn't. All molecules basically follow those simple laws of physics/chemistry/quantum mechanics. The process of disorder in a system follows ordered laws.
If chaos reigned in the universe, it would be entirely logical to assume no designer.
I don't understand. Why couldn't a designer create a chaotic universe, if He so chose? And how is this relevant to our ordered universe?
But then if chaos reigned, you couldn't form the thought for the observation to begin with, so.......
so... what? What does your thought experiment prove? What do the origins of the laws of nature have to do with evolution?
Loosely that would be the habalines typified by the ER 1470 (Homo rudolfensis) speciman VadeRetro mentioned.
But strictly, there are no such things as apes, as a group separate from humans in the way you see it.
Any cladistic grouping that includes orangs with the African Apes will also include all homonoid species, living and extinct.
You are an Ape. Deal with it.
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