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New techniques boost understanding of how fish fins became fingers
Science Daily ^ | 8/17/2016 | University of Chicago Medical Center

Posted on 08/19/2016 2:56:56 PM PDT by JimSEA

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To: b4me

I’m sorry but it’s apparent that you don’t understand what up to date biologists are saying and thus can’t get a perspective. You would profit from an explanation of evolutionary theory from the viewpoint of scientists


41 posted on 08/21/2016 10:54:24 AM PDT by JimSEA
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To: Psalm 73
Psalm 73: "...there is still no proof of one species becoming an entirely different species."

You understand, don't you, that there are no -- zero, nada -- "entirely different species"?
All species share similar DNA and are more or less closely related.
Exactly how closely related depends on how you calculate the alleles, but typically it's said that humans & chimps are 96% the same, cats 90%, cows 80%, mice 75% and even fruit flys share 60% similar DNA as humans.

Point is, all life on Earth shares some similar functions and DNA, and is therefore somewhat related.
Nothing is "entirely different".
So man-made distinctions such as "breed", "sub-species", "species", "genus" & "family", etc., are simply efforts to provide rough ideas as to the degrees of separation between one population and another.

To pick one example, human "races" correspond to breeds in animals and varieties in plants.
All are genetically very closely related (99.9%) and readily interbreed.
Recently, DNA analysis of Neanderthal remains shows them to have been more distantly related than "race" or "breed", but certainly not a separate species.
So they are now classified as a sub-species of humans.

Among bears, for another example, Polar Bears were considered a separate genus from Brown Bears, until natural hybrids were found in the wild, proving they at least occasionally interbreed.
So today Polar & Brown Bears are classified as separate species in the same genus.

That's because scientists consider willingness and ability to successfully interbreed a strong dividing line between populations of the same species versus those of different species, genera & families, etc.

And the key point to grasp is that any two populations of the same species, if separated for long periods of time, will slowly, slowly grow apart genetically, eventually so much we don't classify them as the same species.
But where exactly such lines get drawn is a matter of definitions and conventions.

Psalms 73: "I believe the available evidence would point that these creatures have always been what they are, rather than in the process of becoming an entirely new species."

Studies of mutation rates in many different species show there are a few DNA changes in every generation, most harmless or harmful, seldom beneficial, but these mutations are prevented from degrading the entire genome by natural selection.
Natural selection favors those better adapted to their environments, so if two populations of the same species live in different environments, they will slowly adapt differently to the point of no longer being in the same category.

Occasionally though, speciation can happen relatively quickly, as the man-made speciation of wolves to dogs demonstrates.

42 posted on 08/23/2016 3:45:26 AM PDT by BroJoeK (a little historical perspective...)
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To: BroJoeK
Thank you for your detailed reply - very well thought out and explained. But your comment:

"All species share similar DNA and are more or less closely related."

"similar DNA" is a relative term. That 10% DNA delta between cats and humans is a vast chasm, not a small divot.

The Bible speaks of God creating each thing: "according to its kind" - science can dispute this in theory, but not in fact - the DNA record confirms this at least in part, and it does in no way refute this view of creation.

I would posit that the term "similar" can also point to a common Creator.

43 posted on 08/23/2016 4:11:54 AM PDT by Psalm 73 ("Gentlemen, you can't fight in here - this is the War Room".)
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To: panaxanax

You came with accessories! (Me, too.)


44 posted on 08/23/2016 4:17:44 AM PDT by MortMan (Let's call the push for amnesty what it is: Pedrophilia.)
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To: Psalm 73
Psalm 73: " 'similar DNA' is a relative term.
That 10% DNA delta between cats and humans is a vast chasm, not a small divot."

"Vast chasm"? Sure, relatively speaking, but also amazingly similar, indeed identical in the ways human and feline basic functions work, beginning with the fact of DNA itself.
These similarities, greater or less depending on species, point back through fossil & geological records to common ancestors many, many millions of years ago.

Psalm 73: "The Bible speaks of God creating each thing: 'according to its kind' - science can dispute this in theory, but not in fact - the DNA record confirms this at least in part, and it does in no way refute this view of creation."

That Biblical term, "kinds" corresponds to no scientific category.
For examples, "kinds" does not mean species, genus, family or even phylum.
All "kinds" really means is category, and it refers to the theological idea that everything God created He planned out ahead of time, from the Beginning.
God planned the categories / kinds and then created according to His Plan.

Psalm 73: "I would posit that the term "similar" can also point to a common Creator."

Of course it does, but the Bible says nothing about how God created, and literal mountains of physical evidence point to processes like Evolution as His methodology.

I have no problem with understanding a tiny bit of how God created everything we see or sense today.

45 posted on 08/25/2016 12:03:07 PM PDT by BroJoeK (a little historical perspective...)
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