Fine line between racism and ignorance.

[buddha]

Wow, you\'re fast.

A theory is a body of work meant to describe observations.  So we see things fall, and we can describe the speed of their fall approximately 32 ft /sec^2.  The falling is a fact, the 32 ft/ sec^2 is the theory bit.  That\'s where the distinction comes in.

It\'s true that this is not the common definition of the word \"theory\", but when in a scientific context, our language has to change.   For instance, people use the term \"energy\" in a multitude of ways, but if you\'re talking physics, it cannot mean \"life force\".   Once you enter that arena, the terminology becomes specific.  This is very common problem.

Now, once again I have to disagree with you.  It is possible to loose large chunks of dna even over one generation.  Microsatellites are an example of little chunks, and I\'m trying to think of an example of the former...

[Annah]

It is possible to loose large chunks of dna even over one generation.

 Only if the organism is exposed on a long period of time to radiations.
 In rest, I agree with you about the \"definition\" of the word theory.

 * EDIT *
 Though, there were a few cases where segments disappeared during the DNA replication process. But this could have been an anomaly, and it can\'t be considered a fact yet.

 You mentioned some time ago about apes. I\'ll give you an example. They don\'t have the DNA chain that provides the creation of the \"laringe\" (I can\'t say atm how is named in English), so therefore they cannot speak. Though, we have it. Evolution?

[buddha]

I believe you\'re looking for the word \"larynx\".  Yeah, that\'s a neat case.  I remember reading an article once where they illustrated how the larynx could drop once the skull was re-seated on the neck.  The theory was that the reason apes don\'t have a larynx was because the base of the skull was too close to the vocal chords.

I don\'t know the details.  My impression was the the dna for the larynx is present but not expressed.  This isn\'t my field of expertise, though.

There are birth defects where children are missing parts of a chromosome.  That is a (relatively) enormous amount of genetic data.  Not all of this children are sterile.

Also, think of this.  If the probability of loosing a large chunk of dna in one generation is p, and p is very small.  Then the probability of loosing a large chunk over n generations is

1-(1-p)^n

When n get big, the probability of loosing a large chunk goes to 1.  Thus, even if it\'s an anomaly, as you mention, there are literally trillions of generations being spawned every year over every species, and even the most improbable descent is going to happen eventually.  Couple that with the millions of years we\'ve been on this planet and you cannot exclude it happening at all.

[Annah]

Heh, indeed is something interesting, and I that can\'t exclude. Though, I don\'t embrace it also.
 

There are birth defects where children are missing parts of a chromosome. That is a (relatively) enormous amount of genetic data. Not all of this children are sterile.

 Yes, but these are isolated cases and they express at some generations. Though, the fenotype is heavily affected by the modification of the structure and number of the cromozomes.

 Let\'s take the most known case, which is the one where the 21 pair of cromozomes is affected, this would be the Down syndrome. In this pair it can easily be seen the three cromozomes. But like I said, these are isolated cases and insignificant to the number of the \"normal\" population, and it cannot influence it. And in few cases the person lives over 50 y.o. in this case.

 Turner syndrome? Only women are affected, and they have 45 cromozomes. Though, they\'re incapable of reproduction.

 I can give you many examples, but I\'ll come to the same thing: it\'s insignificant compared to the normal population, that is not affected by them.

[buddha]

Yes, I totally agree that it\'s insignificant compared to the total population.  In fact, all of evolution theory is based on very small changes in dna over long periods of time.

This is what we call the Sidewalk Lemma in probability theory.

IF you have a non-zero chance of being killed by a car every time you cross the street, THEN you will cross the street a finite number of times.

Even very improbable things will happen eventually.  How soon?  Well, that\'s open to debate.  The point is, there have been lots and lots and lots... of opportunities for change in our genetic structure.  Eventually, the small changes add up.  Noone is expecting a child to be born with gills in the near future, but it could happen over millions of years.

Although it would be cool!

[Annah]

We can discuss about this over and over, but I doubt we\'ll solve the mystery of our creation

 It\'s kinda late, and I have to study at history for tomorrow, then to take a bath and err, to sleep

 Buddha, it was a pleasure having this conversation with you on this matter, and who knows, maybe we\'ll have others in the future as well.

 Farewell for now,
 Antonio.

[buddha]

Ciao, good luck in history.  It\'s nice to have civil discourse on these things once in a while.