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Theories - Origin of Life

Discussion of everything related to the Theory of Evolution.

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Re: Theories - Origin of Life

Postby scottie » Sun Oct 30, 2011 11:16 pm

Let me see if I understand you correctly:-

We can observe certain morphological characteristics in a particular group of taxa of say (plants) and use this data to draw conclusions about the evolutionary relationships between these organisms.

Having observed morphological characteristics of this group of different plants we can now examine protein sequence in the same or related plant species to perform cladistic analysis.

We can therefore compare the results of phylogenetic relationships obtained using protein sequences (molecular data) with the results obtained from using morphological data.

For example if cactus (Schlumbergera truncata) and spike-moss (Selaginella) were in the group chosen we would note that they appear to have very similar leaf-like structures, but we would come up with very different evolutionary origins in the molecular data.

How does this support or falsify evolutionary theory. I don’t understand your point.
Could you clarify please?

There is of course controversy within the evolutionary community on the value of morphology in producing lines of decent.
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Re: Theories - Origin of Life

Postby Gavin » Mon Oct 31, 2011 1:16 am

scottie wrote:How does this support or falsify evolutionary theory. I don’t understand your point.


Something about descent with modification. If trees can be built, this supposition is supported. If trees cannot be built, the supposition is falsified. Phenetics has often proven unreliable.
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Postby JackBean » Mon Oct 31, 2011 8:27 am

hey scottie, are you OK? Just one post after weekend? Are you ill or something?

Again, you're referring to post, which I cannot find. Can you copy at least like 5 first lines, so that I can find it? Or click on the name of your post and then copy the link about14351-144.html#p132383 so it will lead directly to your post.
Otherwise I will consider that as refusal to answer the questions.

And I'm also waiting for the answer concerning human origin.
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Re: Theories - Origin of Life

Postby scottie » Mon Oct 31, 2011 3:02 pm

Gavin

Something about descent with modification. If trees can be built, this supposition is supported. If trees cannot be built, the supposition is falsified. Phenetics has often proven unreliable.


There are different views on which is the more reliable Phenetics v Cladistics

But thanks your view is now clearer.

Decent with modification
Or as Richard Dawkins put it in his book
Unweaving the Rainbow: Science, Delusion, and the Appetite for Wonder, p. 201.

What had been distinct species within one genus become, in the fullness of
time, distinct genera within one family. Later, families will be found to have diverged to the point where taxonomists (specialists in classification) prefer to call them orders, then classes, then phyla…Ancestors of two different phyla, say vertebrates and molluscs, which we see as built upon utterly different ‘fundamental body plans’ were once just two species within a genus.

If that is what you mean then,
Yes, that would and indeed does make the theory falsifiable.
So a tree arrived at cladistically showing decent with modification would be one such way to test the data. If a tree cannot be produced then that would constitute falsification.
That's a good test.

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I think you really are quite a nice person, who is trying very hard to be obnoxious.
But you do need to get more practice in. :)
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Postby JackBean » Mon Oct 31, 2011 3:24 pm

so now I'm a nice person? But you have changed significantly since I was away.

Yet, you're still not responding the answers, are you?
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Re: Theories - Origin of Life

Postby scottie » Tue Nov 01, 2011 12:22 pm

Gavin
Organisms such as Trilobites of the Phylum Arthropoda, have articulated body plans, intricate nervous systems and compound eyes. They first appear fully formed at the beginning of the Cambrian strata along with many other phyla of equal complexity.

Aware of this himself Darwin in his “Origin..” stated
“The case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained.”

(ie his views were falsifiable then)

In his 1987 book the “The Blind Watchmaker” page 229 Richard Dawkins comment on this is
“It is as though they [the invertebrate phyla] were just planted there, without any evolutionary history”

In a their 1987 paper titled “Interpreting Great Developmental Experiments: The Fossil Record, paleontologists J.W. Valentine and D.H. Erwin. noted
“transitional alliances are unknown or unconfirmed for any of the [Cambrian] phyla and yet . . .the evolutionary explosion near the beginning of Cambrian time was real and produced numerous [new] body plans.”

In view of the above observations by these recognized authorities, can a tree of “decent with modifications” now be constructed for these organisms that suddenly appeared in the strata of the Cambrian?
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Postby JackBean » Tue Nov 01, 2011 12:32 pm

Well, there is no need for further discussion, if you persist to refuse to answer to my questions, isn't it?
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Re: Theories - Origin of Life

Postby Gavin » Tue Nov 01, 2011 1:31 pm

scottie wrote:In view of the above observations by these recognized authorities, can a tree of “decent with modifications” now be constructed for these organisms that suddenly appeared in the strata of the Cambrian?


I encourage you to read (from beginning to end) your quoted sources, particularly the first two, and to research the Cambrian explosion beyond creationist websites. This topic has been dealt with ad nauseam, and I have no desire to rehash it here. Also, do a search on YouTube for the following terms: "Cambrian explosion", "quote mining", and "Dawkins" - I once came across an amusing short video of Dawkins dealing with the use of quote mining by people such as yourself.
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Re: Theories - Origin of Life

Postby JackBean » Tue Nov 01, 2011 4:31 pm

well, well, well, scottie, it seems, that there are coming clouds over your being here. I have always suspected you twist the meaning of all the quotes you always add (as was the example with NASA saying something about mind, right) and here you got right into your trap:
scottie wrote:In his 1987 book the “The Blind Watchmaker” page 229 Richard Dawkins comment on this is
“It is as though they [the invertebrate phyla] were just planted there, without any evolutionary history”

Apparently, this is a well known example http://rationalwiki.org/wiki/Quote_mini ... ndex_-_QMI
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Re: Theories - Origin of Life

Postby scottie » Wed Nov 02, 2011 3:03 pm

Gavin

I take it then that a tree cannot be constructed.

I don't need to quote mine as is suggested because I have read Dawkin's books. Though I do find books on religion and philosophy quite tedious.

I have also read Origins and have found that much more interesting.

The Cambrian phyla appeared without any Precursors and that is why eminent biologists like Wray, Levinton and Shapiro have attempted to provide molecular evidence for a common ancestor.

There is a clue for you.

Much more interesting than you tube videos.
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Re: Theories - Origin of Life

Postby Gavin » Wed Nov 02, 2011 3:53 pm

Gavin wrote:This topic has been dealt with ad nauseam, and I have no desire to rehash it here.
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Postby JackBean » Thu Nov 03, 2011 1:58 pm

scottie: so you won't comment on the quote mining and you won't answer my questions, right? Well, then I don't see any reason why to keep this thread ongoing. So you should deal with the opened problems or I will lock it here.
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