The Open Mat Forum

Miscellaneous => Evolution(?) => Topic started by: mako on September 20, 2011, 07:14:12 PM

Title: genetic variation
Post by: mako on September 20, 2011, 07:14:12 PM
I had to spin this off of one of the other threads.  The world population argument makes no sense if we stop and look for just a minute.  One of the key issues when you go out to select a dog (or any animal for that matter) from a breeder is you want to know it's pedigree.  This is to ensure that the animal you select wasn't the product of inbreeding.  The underlying principle is genetic variation.  The greater the variation, the fewer opportunities for recessive traits to be inherited.  If our planet started with only 8 human subjects, there isn't sufficient initial genetic variation to support the current population of 6 billion or so.
Title: Re: genetic variation
Post by: ctc on September 20, 2011, 09:04:47 PM
You are kidding, right?  Have you no clue how genetic information is contained in DNA?

BTW - the pedigree with dogs shows "inbreeding".  That is how man develops different traits in dogs.
Title: Re: genetic variation
Post by: mako on September 20, 2011, 09:38:35 PM
I know precisely how DNA works.  There is not enough DNA contained in 8 specimens of the species Homo Sapiens to account for the current genetic variation.   The Human Genome Project identified between 20,000 and 25,000 human genes.  We could not have the modern human genetic variation if we started with only 8 specimens.  Ask any reputable biologist or geneticist.  Your pastor does not count.  You really should avoid commenting on topics regarding science.  Your ignorance is so profound I am not sure where to begin.
Title: Re: genetic variation
Post by: drmuscle on September 20, 2011, 10:10:28 PM
Dog are inbred almost exclusively. In the breeding world it's refereed to as line breeding.
Title: Re: genetic variation
Post by: Ray Brinzer on September 20, 2011, 10:26:16 PM
I know precisely how DNA works.

Wow.
Title: Re: genetic variation
Post by: mako on September 20, 2011, 11:09:33 PM
Yeah I am guilty of exaggeration, but I do know enough to understand genetic variation and that 8 members of a species are insufficient to maintain the current variation.
Title: Re: genetic variation
Post by: ctc on September 21, 2011, 08:32:45 AM
Yeah I am guilty of exaggeration, but I do know enough to understand genetic variation and that 8 members of a species are insufficient to maintain the current variation.
Apparently, you are not smart enough to know that according to Richard Dawkins, there is enough information in the DNA of the simpliest life form known to man to fill 1000 volumes of Encyclopedia Britannica to .  That would be a stack about 70 yards tall.  Your "20,000 identified" is simply ignorant.  Obviously, you are clueless.  Thank you, though, for your continued personal attacks.  It makes you look "superior".   ::)
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 10:02:45 AM
Yeah I am guilty of exaggeration, but I do know enough to understand genetic variation and that 8 members of a species are insufficient to maintain the current variation.
Apparently, you are not smart enough to know that according to Richard Dawkins, there is enough information in the DNA of the simpliest life form known to man to fill 1000 volumes of Encyclopedia Britannica to .  That would be a stack about 70 yards tall.  Your "20,000 identified" is simply ignorant.  Obviously, you are clueless.  Thank you, though, for your continued personal attacks.  It makes you look "superior".   ::)

The clueless one is the crazy texas coach once again.  mako is correct the number of identified in humans is in the 20000 to 25000 range.  Open mouth insert foot dumb dumb.

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/H/HGP.html

Quote
1. The number of genes turned out to be much smaller than once predicted.
The two groups came up with slightly different estimates of the number of protein-encoding genes, but both in the range of 30 to 38 thousand:
•barely two times larger than the genomes of
◦Drosophila (~17,000 genes)
◦C. elegans (<22,000 genes)
•and representing only 1– 2% of the total DNA in the cell;
•and a third of the 100,000 genes that many had predicted would be found.
•(By 2011, the number had been reduced to some 21,000.)
Are the tiny roundworm and fruit fly almost as complex as we are?

Probably not, although we share many homologous genes (called "orthologs") with both these animals.
But,

•many of our protein-encoding genes produce more than one protein product (e.g., by alternative splicing of the primary transcript of the gene). On average, each of our ORFs produces 2 to 3 different proteins.
So the human "proteome" (our total number of proteins) may be 10 or more times larger than that of the fruit fly and roundworm.

•A larger proportion of our genome
◦encodes transcription factors
◦is dedicated to control elements (e.g., enhancers) to which these transcription factors bind.
The combinatorial use of these elements probably provides much greater flexibility of gene expression than is found in Drosophila and C. elegans.
Title: Re: genetic variation
Post by: drmuscle on September 21, 2011, 10:13:56 AM
But the first single cell organism had enough DNA to give way to every creature on earth?
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 10:23:53 AM
But the first single cell organism had enough DNA to give way to every creature on earth?

Actually scientist now believe the first single celled organisms had no DNA whatsoever.  The precurser to DNA is a simpler form called RNA, but they believe they did not have that either, they had another mechanism, much less developed and RNA and DNA evolved from this precursor.
Title: Re: genetic variation
Post by: ctc on September 21, 2011, 10:25:12 AM
But the first single cell organism had enough DNA to give way to every creature on earth?
Quit making Mako look foolish.  He is doing fine on his own.   ;D
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 10:26:28 AM
But the first single cell organism had enough DNA to give way to every creature on earth?
Quit making Mako look foolish.  He is doing fine on his own.   ;D

the crazy texas coach just cannot help it, he likes being the forum jester.  Open mouth, insert foot again.
Title: Re: genetic variation
Post by: drmuscle on September 21, 2011, 10:40:33 AM
At some point there had to be a single first one.
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 10:45:42 AM
At some point there had to be a single first one.

Yes but it did not have to have DNA.  DNA could have taken many millions of years to develop from the precursor materials.

From the September 2009 issue of Scientific American:

Quote
Life on Earth
BY Alonso Ricar do and Jack W. Szostak
Fresh clues hint at how the
first living organisms arose
from inanimate matter

On the other hand, the paradox would disappear if the first organisms did not require proteins at all. Recent experiments suggest it would have been possible for genetic molecules similar to DNA or to its close relative RNA to form spontaneously. And because these molecules can curl up in different shapes and act as rudimentary catalysts, they may have become able to copy themselves—to reproduce—without the need for proteins. The earliest forms of life could have been simple membranes made of fatty acids—also structures known to form spontaneously—that enveloped water and these self-replicating genetic molecules. The genetic material would encode the traits that each generation handed down to the next, just as DNA does in all things that are alive today. Fortuitous mutations, appearing at random in the copying process, would then propel evolution, enabling these early cells to adapt to their environment, to compete with one another, and eventually to turn into the lifeforms we know.
Title: Re: genetic variation
Post by: Cougar1 on September 21, 2011, 11:04:28 AM
But the first single cell organism had enough DNA to give way to every creature on earth?

+1 for drmuscle
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 11:08:43 AM
But the first single cell organism had enough DNA to give way to every creature on earth?

+1 for drmuscle

-1 for cougar, he should have read on and seen that scientist do not believe the first living singular celled creatures had any DNA whatsoever.  It took millions of years for that to develop from its precursors.
Title: Re: genetic variation
Post by: mako on September 21, 2011, 12:44:45 PM
Back to the issue of genetic variance.  If we start with only 8 specimens,  there is not enough genetic variance among them to support a population of 5 billion plus.  When too few specimens of a population are used to create a larger population, a genetic bottleneck.  occurs.  This isn't a term I pulled out of my arse, there is plenty of literature on the problem.  Two examples of the genetic bottleneck can be found with the northern elephant seal, and also the cheetah.  In both species the genetic variance is close to zero.  Both of these populations were dwindled to fewer than 100 members.  The current populations of both species have members which are all genetically identical.  If the human race began with only 8 members, then all 5 billion plus of us would be genetically identical and that certainly is not the case.
Title: Re: genetic variation
Post by: drmuscle on September 21, 2011, 01:20:31 PM
If a genetic bottle neck disproves creation theory then it also has to disprove evolution. There is no way we get from single cells to every species on earth and every intermediate transition if the bottle neck theory is valid. If every thing gives way to the next then it had to be in the first building blocks. Your example of dogs should show you just how much variety there is in the generic code. Mixed breeding continues to yield dogs with entirely new characteristics right in our own life times.
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 01:31:44 PM
If a genetic bottle neck disproves creation theory then it also has to disprove evolution. There is no way we get from single cells to every species on earth and every intermediate transition if the bottle neck theory is valid. If every thing gives way to the next then it had to be in the first building blocks. Your example of dogs should show you just how much variety there is in the generic code. Mixed breeding continues to yield dogs with entirely new characteristics right in our own life times.

Wrong, beneficial mutations help write the building blocks of all life, you are completely clueless about the science of biological evolution.  You should try to refrain from commenting on what you do not understand because it simply put makes you look stupid and foolish.
Title: Re: genetic variation
Post by: drmuscle on September 21, 2011, 04:52:33 PM
So a single cell organism with no DNA can give way to every living creature ever to exist, but 8 humans lack enough genetic variation to account for the various races and differences in people. I must sound so stupid.
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 05:19:58 PM
So a single cell organism with no DNA can give way to every living creature ever to exist, but 8 humans lack enough genetic variation to account for the various races and differences in people. I must sound so stupid.

You do drmusclehead, trust me you do. It is people far far far far far smarter than you, and even smarter then me ;) who have figure this stuff out.  Of course you can take the intellectually lazy and immature way out and say it all happened by magic which is the world of fantasy and make believe.
Title: Re: genetic variation
Post by: drmuscle on September 21, 2011, 05:31:41 PM
You have just totally exposed your self as an anti religion zealot. You lack all objectivity because you being a self anointed intellectual know deep down that there is no way there could ever be a god and science must at all cost prove this. This thinking has brought us the global warming scam also endorsed by self anointed intellectuals.
Title: Re: genetic variation
Post by: coachsparky on September 21, 2011, 05:37:46 PM
You have just totally exposed your self as an anti religion zealot. You lack all objectivity because you being a self anointed intellectual know deep down that there is no way there could ever be a god and science must at all cost prove this. This thinking has brought us the global warming scam also endorsed by self anointed intellectuals.

No you prove your ignorance once again drmusclehead.  I actually believe in a God.  It has no personality, no gender and does not interact with human beings.  It is the same God that Stephen Hawkings and Albert Einstein believe it bu it is still God and it is the one and only God that has ever or could ever exist.  It is called Nature or the Universe and It has indeed created great things.  And you are so ignorant you still think there was some sort of global warming scam even that that whole argument was discredited some time ago.
Title: Re: genetic variation
Post by: ctc on September 21, 2011, 09:44:43 PM
You have just totally exposed your self as an anti religion zealot. You lack all objectivity because you being a self anointed intellectual know deep down that there is no way there could ever be a god and science must at all cost prove this. This thinking has brought us the global warming scam also endorsed by self anointed intellectuals.
I don't argue with a moron.  He is on my ignore list.
Title: Re: genetic variation
Post by: mako on September 21, 2011, 10:13:09 PM
One of the pitfalls of discussing scientific issues is being on the same page.  At this point, we don't even speak the same language much less being on the same page.  I am not talking about species origin or how life originated on the planet.  I am merely speaking to the flawed argument that the current world's population originated from 8 specimens.  I do not have a PhD, but I do have a pretty good working knowledge and education in physiology and genetics.  I certainly do not know how the first life came to be, and for all intents and purposes it doesn't concern me.  What does concern me is using flawed methodologies when discussing population growth curves.
Title: Re: genetic variation
Post by: ctc on September 22, 2011, 08:00:10 AM
You have trouble with 8 people?  Apparently, you have never heard of "Mitochondrial Eve".  You would really have problems with 2 people.  Obviously, you have no idea how much information is actually contained in DNA.  It is beyond comprehension.  There was no regional isolation with the early parents.  The loss of information didn't begin to happen yet.
Title: Re: genetic variation
Post by: coachsparky on September 22, 2011, 10:09:34 AM
You have just totally exposed your self as an anti religion zealot. You lack all objectivity because you being a self anointed intellectual know deep down that there is no way there could ever be a god and science must at all cost prove this. This thinking has brought us the global warming scam also endorsed by self anointed intellectuals.
I don't argue with a moron.  He is on my ignore list.

Let's face it crazy texas coach, you don't argue with me because you know I am your intellectual superior.  I have decimated your ignorant, backward, redneck ass everytime you have tried to engage me.  I actually use science and facts and all you use is a book written by primative men some 6000-2000 years ago.  You have no chance when the odds are so obviously stacked against you.
Title: Re: genetic variation
Post by: coachsparky on September 22, 2011, 10:11:40 AM
You have trouble with 8 people?  Apparently, you have never heard of "Mitochondrial Eve".  You would really have problems with 2 people.  Obviously, you have no idea how much information is actually contained in DNA.  It is beyond comprehension.  There was no regional isolation with the early parents.  The loss of information didn't begin to happen yet.

The mitochondrial eve had many Adams so it is far more then two people crazy texas coach, but perhaps you did not realize that.  I am not too surprised that you were ignorant of that fact.