Odds of many successive beneficial mutations are minuscule (Talk.Origins)

Response ArticleThis article (Odds of many successive beneficial mutations are minuscule (Talk.Origins)) is a response to a rebuttal of a creationist claim published by Talk.Origins Archive under the title Index to Creationist Claims.

Index

Claim CB940.1:

Successful production of a 200-component functioning organism requires at least 200 beneficial mutations. The odds of getting that many successive beneficial mutations is r²⁰⁰, where r is the rate of beneficial mutations. Even if r is 0.5 (and it is really much smaller), that makes the odds worse than 1 in 10⁶⁰, which is impossibly small.

Source:

• Morris, Henry M., 1972. The mathematical impossibility of evolution. Acts & Facts 2.
• Morris, Henry M., 2003. The mathematical impossibility of evolution. Back to Genesis 179, pp. b-c.

CreationWiki response:

(Talk.Origins quotes in blue)

1. Morris's calculation assumes that all the beneficial mutations must occur consecutively with no other mutations occurring in the meantime. When one allows harmful mutations that get selected out along the way, 200 beneficial mutations would accumulate fairly quickly -- in 200/r generations using the assumptions of Morris's model.

Talk Origins figure assumes that all harmful mutations are selected out. This would be the case for the first one, since it would only have one part; after all if it lost that part it would be dead. However, the one with two parts could lose one, still have one part remaining and continue to live. Thus for Morris’ simplified case his calculations are correct.

(The real world is quite a bit more complicated yet. In particular, large populations and genetic recombination via sex can allow beneficial mutations to accumulate at a greater rate.)

True, but the probability of getting a single truly beneficial mutation is at best many orders of magnitude lower than one half and most likely impossible.