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To: bobdsmith
Thank you for well constructed reply. Perhaps you could reference where those calculations can be found in a succinct format. Nonetheless, please permit me to pose some questions for your consideration.

I must point out that your process has neglected to consider the negative probabilities of a changing natural selection pressures. As this is a well known phenomenon, it must be accounted for.

Additionally, I must also ask how many mutations are required for one species to “evolve” into another completely different species. While you generously (for my benefit) postulate a 1% beneficial rate, from a mathematical perspective, I must also inquire as to how many of these mutations must be sequential for a new species to appear.
250 posted on 04/15/2006 6:02:30 PM PDT by Lucky Dog
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To: Lucky Dog
Additionally, I must also ask how many mutations are required for one species to “evolve” into another completely different species. While you generously (for my benefit) postulate a 1% beneficial rate, from a mathematical perspective, I must also inquire as to how many of these mutations must be sequential for a new species to appear.

That depends on the mutations, doesn't it? The key point is that after thousands of generations, numerous mutations have been favorably selected, and have spread through the population. Others have been de-selected (by early death or reproductive failure) and have been removed from the population. The gene pool (that's the ball to keep your eye on) is then different from what it once had been. It changes every generation, somewhat, but over a great many generations the changes are cumulative. The creatures in the breeding population never notice this, because from one generation to the next, the effect is minimal. It's mostly apparent only when an ancestral fossil is found and compared to the current version.

It can also become apparent if the population is divided, perhaps by a river or something, and each takes it's genetic material and goes a separate way. In time (again, we're talking about thousands of generations) the two populations -- if they were reunited -- probably won't be one breeding population any more.

253 posted on 04/15/2006 6:13:32 PM PDT by PatrickHenry (Yo momma's so fat she's got a Schwarzschild radius.)
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To: Lucky Dog
Perhaps you could reference where those calculations can be found in a succinct format

The mutation rate I used was from the figure you quoted of "one mutation per locus per 10^5 to 10^6 gametes". The figure for the number of genes in a typical mammal I used the number of genes in humans. I believe it is somewhere in the tens of thousands.

I must point out that your process has neglected to consider the negative probabilities of a changing natural selection pressures. As this is a well known phenomenon, it must be accounted for.

A changing environment does not affect the number of mutations that occur over time. All I have estimated is the number of mutations within genes that would be expected to occur over 1,000,000 years in a population of 1,000 mammals with a generation time of one year. The value is about 10 million. I do not have the expertise to go further and apply population genetics equations to figure out the proportion of those mutations that would fix. Neither do I know good estimate figures of the proportion of mutation that are harmful, or the proportion that are neutral or beneficial.

Additionally, I must also ask how many mutations are required for one species to “evolve” into another completely different species.

I have no idea how many specific mutations it would take. It would likely be different depending on the species involved. But I do not think the question should be how many mutations leads to speciation. Whether or not a change represents speciation is irrelevant to the probability of it occuring in a given time.

261 posted on 04/15/2006 6:41:29 PM PDT by bobdsmith
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To: Lucky Dog
Since you seem to want to try to construct a mathematical model of evolution to 'test' it....I was wondering what you think of the mathematical models that are being used to support the hypothesis that humans are responsible for global warming....and whether you think the earth's meteorological system (global temperature system?) is a more or less complex system than the earth's biological system.
263 posted on 04/15/2006 6:44:58 PM PDT by ml1954 (NOT the disruptive troll seen frequently on CREVO threads.)
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To: Lucky Dog
Here's an on-line tutorial in population genetics. It's geared toward students studying to become veterinarians. This one is more mathematical.

There are lots of books and web resources on the topic. Don't reinvent the wheel. Enjoy!

432 posted on 04/16/2006 12:17:29 PM PDT by Virginia-American
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