Originally posted by bbarr This question doesn't make any sense. Given a lottery with those odds, there will still be a winner. Prior to the lottery drawing, the proposition that any particular player will win will be massively improbable, but since there will be a winner of the lottery, the proposition that no particular player will win is false.
Fair enough. But the question is not whether there will be a winner, but whether the winner will be you.
Originally posted by DoctorScribbles No. 0 chances in ten thousand trillion trillion trillion would be considered impossible. That's just what impossible means in such discrete problems.
In the same way that (ten thousand trillion trillion trillion minus one) chances out of ten thousand trillion trillion trillion is not considered to be a certainty.
Okay. Well lets go with reasonably possible as I'm sure the answer to our little exercise will be greater than 0. What would you think are reasonably possible chances?
Originally posted by Halitose Okay. Here's my proposed framework in order to calculate the odds of mutation creating a new species.
1. What is the chance of getting a mutation.
2. What fraction of the mutations have a selective advantage.
3. How many replications there are in each step of the chain of selection.
4. How many of those steps there have to be to achieve a new species.
How would you calculate the probabilities in either (1) or (2)?
Originally posted by Halitose Fair enough. But the question is not whether there will be a winner, but whether the winner will be you.
No, that is not the question. Your original question concerned speciation in general, not the probability that any particular organism (or species) would result from evolution. Showing it massively improbable that I would result from an evolutionary process is as irrelevant to evolutionary theory as showing it massively improbable that a particular wave would exist on surface of the ocean is to fluid dynamics.
Originally posted by bbarr How would you calculate the probabilities in either (1) or (2)?
(2) is a little tricky.
"The probabilities that a mutation will survive or eventually spread in the course of evolution tend to vary inversely with the extent of its somatic effects. Most mutations with large effects are lethal at an early stage for the individual in which they occur and hence have zero probability of spreading. Mutations with small effects do have some probability of spreading and as a rule the chances are better the smaller the effect."—*George Gaylord Simpson, "Uniformitarianism: An Inquiry into Principle Theory and Method in Geohistory and Biohistory," Chapter 2; in *Max Hecht and *William C. Steeres, ed., Essays in Evolution and Genetics (1970), p. 80.
Originally posted by Halitose Evolution: The supposed change in the genetic composition of a population during successive generations, as a result of natural selection acting on the genetic variation among individuals, and resulting in the development of new species.
What are its requirements? Is it statistically possible?
Evolution and the formation of new species has been observed. Therefore it is 100% likely.
Originally posted by AThousandYoung Evolution and the formation of new species has been observed. Therefore it is 100% likely.
The thing that puzzles me about arguments against evolution is that none of them address intra-species genetic variance and/or intra-species deviations of the DNA sequence.
Random mutation is not neccessarily the only mechanism that produces speciation since epigenetic markers may well determine which genetic variants survive a radical environmenal change.
A possibly revisiting Lamarckian evolution (with a bit of help from epigenitics) may well be the next step in understanding the mechanism that produced evolutionary change.
Originally posted by Halitose Great. That solves our problem. I think just one such "observed" case would be enough, if you would be so kind as to share your observations.
Didn't you and I already go over this?
Three species of wildflowers called goatsbeards were introduced to the United States from Europe shortly after the turn of the century. Within a few decades their populations expanded and began to encounter one another in the American West. Whenever mixed populations occurred, the specied interbred (hybridizing) producing sterile hybrid offspring. Suddenly, in the late forties two new species of goatsbeard appeared near Pullman, Washington. Although the new species were similar in appearance to the hybrids, they produced fertile offspring. The evolutionary process had created a separate species that could reproduce but not mate with the goatsbeard plants from which it had evolved."
Originally posted by bbarr No, that is not the question. Your original question concerned speciation in general, not the probability that any particular organism (or species) would result from evolution. Showing it massively improbable that I would result from an evolutionary process is as irrelevant to evolutionary theory as showing it massively improbable that a particular wave would exist on surface of the ocean is to fluid dynamics.
I feel like pasting my favorite Murray Gell Mann quote here, but instead I will just paraphrase :
15 Sep '05 19:48
Evolution
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