Re: genetic diversity (was Newsweek)
Frosch (dexter@aries.scs.uiuc.edu)
13 Feb 95 23:35:36 GMT
htrst1+@pitt.edu (Henry T Robertson) writes:
>In article <dexter.792713841@aries>, Frosch <dexter@aries.scs.uiuc.edu> wrote:
>>htrst1+@pitt.edu (Henry T Robertson) writes:
>>>In article <dexter.792707726@aries>, Frosch <dexter@aries.scs.uiuc.edu> wrote:
>>>> i guess you're trolling again, aren't you?
>>>No I'm not trolling. Are you saying all DNA is genetic? How did different
>>>species come to have differing numbers of base pairs and chromosomes?
>> DNA is the genetic material. judging whether a stretch of DNA
>>constitutes 'a gene' or not relies on definitions which are changing
>>rapidly with time. 'this is not a gene' is most often not a statement
>>one can make with confidence. what do _you_ mean by it?
>I see, so you were asking what my opinion is of what constitutes
>non-genetic DNA. You were not trying to say that there is no such thing
>as non-genetic DNA. I was going to ask what planet you study biology on...
'non-genetic DNA' is a nonsense phrase. and yes, in the context
you speak of, all DNA is genetic. for this to hold, it does not need
to be true that all DNA consists of genes. if you wish to speak of
'non-gene DNA', by all means go ahead, that is a different topic.
should i be surprised you didn't answer my question? would you
like to further elaborate on what you mean with the assertion that
differences between humans and chimpanzees are 'not genetic'?
>Anyway, to repeat my question, how did different species come to have
>differing numbers of base pairs and chromosomes?
logical inference suggests duplication, breakage and fusion. feel
free to add to the list if you can.
>Obviously, random breeding
>between humans do not occasionally produce a chimp, or vice versa.
>Gene mixing does not increase or decrease the number of base pairs.
obviously, speciation has occurred. how do you arrive at your
'obvious' conclusion that it cannot?
>> i don't understand your fascination with chromosome number. we
>Fascination?? I only take it up as one reason why some species cannot
>reproduce with one another. My question is how did those differing numbers
>of chromosomes come about? There is a fellow by the name of
>Dr. Periannan Senapath, author of _Independent Evolution of Organisms_,
>web page http://www.fullfeed.com, who claims that random breeding cannot
>cause the evolution of entirely different organisms. Is he considered a
>kook by the biological community?
i have no idea, nor do i care.
>>had this discussion quite some time ago. you were convinced that a
>>chimpanzee with down's syndrome or an equivalent disorder should be
>>the same as a human if it had the same number of chromosomes as a
>>human...
>Say what? I do recall having a discussion on whether hypothetically,
>humans inbred with down's-syndrome parents will become chemically
>incompatible with normal humans and thus constitute a different "species".
>You did not seem to have a good answer for that one, nor did you recall
>exactly how many chromosomes humans have.
either your memory fails you, or your honesty.
>>>I'm not a biologist.
>> many people who intensely occupy themselves for long periods of
>>time with an issue outside their field, make at least some effort to
>>acquaint themselves with the fundamentals of that topic...
>Intensely? Neh. I've got too many other interests. I've used usenet
>in the past to ask various esoteric questions in a variety of fields,
>so I trust it will work this time also unless you want to turn it into an
>ad-hominem thread that causes everyone to shy away from participating.
>I've experienced that in the past too, if the questions were too politically
>provocative.
so you are trolling...
annette
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