Page 29 of 30
Posted: Thu Jun 21, 2007 7:44 am
by Digit
Surely Cog ALL mutations are random.
My point is that climate change etc does not initiate mutations, only works on existing ones.
As I see it, any other other interpretation brings us back to Lamarck.
Lamarck
Posted: Thu Jun 21, 2007 9:07 am
by Cognito
Surely Cog ALL mutations are random.
My point is that climate change etc does not initiate mutations, only works on existing ones.
As I see it, any other other interpretation brings us back to Lamarck.
Lamarck believed that mutations during the lifetime of the person could be passed on to progeny, and I don't believe that. However, I do believe an environmental stressor will naturally select for an already mutated gene(s) or a rare, randomly elicited mutagenic response. We might be splitting hairs here.

Posted: Thu Jun 21, 2007 10:39 am
by Digit
Yes I think we are Cog. But Lamarck was of the opinion that a blacksmith who developed a lot muscle, for example, would have muscular children, and I interpreted what has been said in this thread as support for that idea.
I seem to remember Marduk getting hot under the collar with me on the subject.
Lamarck
Posted: Thu Jun 21, 2007 12:50 pm
by Cognito
Yes I think we are Cog. But Lamarck was of the opinion that a blacksmith who developed a lot muscle, for example, would have muscular children, and I interpreted what has been said in this thread as support for that idea.
Nope ... you and I are talking natural selection of pre-existing genetics with some random mutations thrown in just to confuse people.

Posted: Thu Jun 21, 2007 2:25 pm
by Digit
You are correct Cog, but now I AM confused.
Are you saying that, if a species were exposed to a set of conditions that it was not pre-adapted to survive in, it would then adapt itself and do so and fast enough to breed and pass on that improvement?
Posted: Thu Jun 21, 2007 4:55 pm
by Minimalist
Consider the analogy of a plane crash in the middle of the Greenland glacier.
There are a handful of survivors. They could easily adapt to drinking snow. They could probably adapt to eating whatever they could catch.
However, if they could not adapt to the freezing temperatures neither of the others makes any difference.
In that case the conditions of life are so arduous that there is no survival for the group longterm.
However, crash the plane on a warm south sea island. There's a spring. There is food from the sea or trees. There are birds. The temperature is not going to kill anyone. The conditions are such that long term survival was possible.
In that instance the group could survive for quite some time and the ones who would be most likely to survive long enough to reproduce were those who could best adapt to the new conditions and fight off dysentery or bacterial infections, etc.
So, the strongest man who built up his muscles from carrying logs would not necessarily pass that trait on to his offspring. But, the child would have a genetic predisposition to a better immune system, as an example.
Anyway, I think that's where you guys are going with this.
Re: Lamarck
Posted: Thu Jun 21, 2007 5:31 pm
by Charlie Hatchett
Cognito wrote:Yes I think we are Cog. But Lamarck was of the opinion that a blacksmith who developed a lot muscle, for example, would have muscular children, and I interpreted what has been said in this thread as support for that idea.
Nope ... you and I are talking natural selection of pre-existing genetics with some random mutations thrown in just to confuse people.

Agreed. Natural Selection acts on what's there. It doesn't cause new combinations.
Adaptation
Posted: Thu Jun 21, 2007 5:41 pm
by Cognito
Are you saying that, if a species were exposed to a set of conditions that it was not pre-adapted to survive in, it would then adapt itself and do so and fast enough to breed and pass on that improvement?
I am saying that if the subject population is large enough, a random mutagenic response could occur that would be beneficial in adapting an individual and some of its offspring to the new environment. Although rare, it happens. That is how, in the Microbilogy 101 experiment, bacteria in the petri dish survive and grow in ultraviolet radiation.
Posted: Mon Jun 25, 2007 6:55 pm
by Beagle
http://www.baltimoresun.com/news/nation ... -headlines
WASHINGTON // Researchers studying Neanderthal DNA say it should be possible to construct a complete genome of the ancient hominid despite the degradation of the DNA over time.
There is also hope for reconstructing the genome of the mammoth and cave bear, according to a research team led by Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany
A progress report from Paabo. Sounds like they're getting closer.
Archaeologica News.
Ancient DNA Sequencing
Posted: Mon Jun 25, 2007 10:32 pm
by Cognito
Yes, Beags. And for those who love the science behind the efforts of Max Planck, Lawrence Livermore and Berkeley:
http://www.jgi.doe.gov/science/highligh ... n0705.html
Posted: Tue Jun 26, 2007 7:21 am
by Digit
Being a card carrying member of the awkward squad I would also like to see the genome for Cro-Magnon.
IMO much of the support for him being an early HSS is based on the same predudice as relegated HSN to the status of 'Brute'.
Cro Magnon
Posted: Tue Jun 26, 2007 12:25 pm
by Cognito
Being a card carrying member of the awkward squad I would also like to see the genome for Cro-Magnon.
IMO much of the support for him being an early HSS is based on the same predudice as relegated HSN to the status of 'Brute'.
Digit, I am yDNA R1b and mtDNA U5a ... in other words, Cro Magnon. And yes, I am a brute. When I don't win a sprint I blame it on the ancestral Neanderthal in the woodpile.

Re: Cro Magnon
Posted: Tue Jun 26, 2007 12:26 pm
by Charlie Hatchett
Cognito wrote:Being a card carrying member of the awkward squad I would also like to see the genome for Cro-Magnon.
IMO much of the support for him being an early HSS is based on the same predudice as relegated HSN to the status of 'Brute'.
Digit, I am yDNA R1b and mtDNA U5a ... in other words, Cro Magnon. And yes, I am a brute. When I don't win a sprint I blame it on the ancestral Neanderthal in the woodpile.


Posted: Tue Jun 26, 2007 12:28 pm
by Digit
Being weak on the DNA subject I've been doing some reading from the net and I noticed that the sensible researchers point out the small size of samples.
Quite!
According to a book I'm currently reading it has been estimated that the chances of early hominids being fossilised is one person per 100 million!
I other words trying to work out the realtionships in the modern population of the States or greater Europe from 3 samples!
Sound like a lot of guess work involved.
Posted: Tue Jun 26, 2007 12:32 pm
by Digit
Like I said Cog, I like the awkward questions. So untill Cro-Magnon's genome is produced how do you know that you are he?
Like me, you claim not to fit the stereotypical CM skeleton, which is why I suspect that HSN is in there somewhere.
Have a look at my earlier post on the subject, the figures came as quite a shock to me I must admit.