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Oceanic ;5528799 said:Drew_Ali;5522796 said:@Oceanic......
*crickets chirping*
I apologize for the delayed response; I'm not here 24/7.
You have yet to find the example of where your article states that the common ancestor theory is out the window. As I've stated, the tree of life as a concept has been proposed to be discarded and then replaced with the web to more accurately explain how evolution occurs.
Darwin assumed that descent was exclusively "vertical", with organisms passing
traits down to their offspring. But what if species also routinely
swapped genetic material with other species, or hybridised with
them? Then that neat branching pattern would quickly degenerate into
an impenetrable thicket of interrelatedness, with species being
closely related in some respects but not others.
We now know that this is exactly what happens. As more and more
genes were sequenced, it became clear that the patterns of
relatedness could only be explained if bacteria and archaea were
routinely swapping genetic material with other species--often
across huge taxonomic distances--in a process called horizontal
gene transfer (HGT).
http://postbiota.org/pipermail/tt/2009-February/004416.html
Drew_Ali;5515830 said:Gold_Certificate;5515821 said:How does this involve Darwin?
This.....
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"For much of the past 150 years, biology has largely concerned itself
with filling in the details of the tree. "For a long time the holy
grail was to build a tree of life," says Eric Bapteste, an
evolutionary biologist at the Pierre and Marie Curie University in
Paris, France. A few years ago it looked as though the grail was
within reach. But today the project lies in tatters, torn to pieces
by an onslaught of negative evidence. Many biologists now argue that
the tree concept is obsolete and needs to be discarded. "We have no
evidence at all that the tree of life is a reality," says Bapteste.
That bombshell has even persuaded some that our fundamental view of
biology needs to change."
http://postbiota.org/pipermail/tt/2009-February/004416.html
On The Origin of Species 22 years later, Darwin's spindly tree had grown into a mighty oak. The book contains numerous references to the tree and its only diagram is of a branching structure showing how one species can evolve into many.
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The tree-of-life concept was absolutely central to Darwin's thinking, equal in importance to natural to natural selection, according to biologist W. Ford Doolittle of Dalhousie University in Halifax, Nova Scotia, Canada. Without it the theory of evolution would never have happened. The tree also helped carry the day for evolution. Darwin argued successfully that the tree of life was a fact of nature, plain for all to see though in need of explanation. The explanation he came up with was evolution by natural selection. ...
From tree to web
"As it became clear that HGT was a major factor, biologists started to realise the implications for the tree concept. As early as 1993, some were proposing that for bacteria and archaea the tree of life was more like a web. In 1999, Doolittle made the provocative claim that "the history of life cannot properly be represented as a tree" (Science, vol 284, p 2124). "The tree of life is not something that exists in nature, it's a way that humans classify nature," he says."
Drew_Ali;5528821 said:I have had some downtime.............
Drew_Ali;5528821 said:I made a spinoff thread in the R&R for your feelings........
Oceanic ;5528969 said:that neat branching pattern would quickly degenerate into
an impenetrable thicket of interrelatedness, with species being
closely related in some respects but not others.
We now know that this is exactly what happens. As more and more
genes were sequenced, it became clear that the patterns of
relatedness could only be explained if bacteria and archaea were
routinely swapping genetic material with other species--often
across huge taxonomic distances--in a process called horizontal
gene transfer (HGT).[/i]http://postbiota.org/pipermail/tt/2009-February/004416.html
Oceanic ;5529042 said:The only thing that says is that descent was thought to be "exclusively vertical" when now it shows itself not to be. The web conceptualization still does not get rid of common descent.
Oceanic ;5528969 said:that neat branching pattern would quickly degenerate into
an impenetrable thicket of interrelatedness, with species being
closely related in some respects but not others.
We now know that this is exactly what happens.
It became clear that the patterns of
relatedness could only be explained if bacteria and archaea were
routinely swapping genetic material with other species--often
across huge taxonomic distances
Oceanic ;5529042 said:The web conceptualization still does not get rid of common descent. A web still springs from one point.
![]()
Drew_Ali;5529059 said:A web springs from one creator........
Drew_Ali;5529048 said:C'mon son.........
Drew_Ali;5529112 said:As I take tokes of the marijuana smoke.................
Oceanic ;5529127 said:Drew_Ali;5529112 said:As I take tokes of the marijuana smoke.................
I would suppose you're on something other than marijuana
Again, you would have to explain why the common descent theory should be discarded.
Oceanic ;5529159 said:Peace
Oceanic ;5529101 said:Drew_Ali;5529059 said:A web springs from one creator........
that "creator" being the first lifeform, i.e. common descent