Dawkins’s advice shows that he didn’t understand probability. . . . Dawkins said that a creature the lives millions of years would have a different feeling for the meaning of the chance of an event than we have. If the alien lives a hundred million years, he could have played very many hands of bridge Then, Dawkins said, it would not be unusual for him to see a ‘perfect’ bridge hand where each player was dealt thirteen cards of the same suit. ‘They will expect to be dealt a perfect bridge hand from time to time, and will scarcely trouble to write home about it when it happens.’
He’s wrong. One can easily calculate the chance of Dawkins’s alien experiencing a perfect bridge hand at least once in his lifetime. The shance of getting such a hand in one deal is 4.47 x [10 to the minus 28th power]. If the alien plays 100 bridge hands every day of his life for 100 million years, he would play about 3.65 x [10 to the 12th power] hands. The chance of his seeing a perfect hand at least once in his life is then 1.63 x [10 to the minus 15th power], or about one chance in a quadrillion. That’s less than Dawkins’’ chance of coming to New York for two weeks and winning the lottery twice in a row. Would he bother to write home about it?
Tags: aliens probability dawkins origin-of-life
Only a minority of biologists today hold that the variation of evolution cannot be random. In this point the minority are on more solid ground than the majority. If we want to gain a true insight into evolution, we must look to nonrandom variation.
Lee SpetnerNeo-Darwinians do cite some examples of evolution they claim the NDT explains. Natural selection can indeed account for the replacement of light-colored moths with dark ones when the lichens get covered with soot. But no one has shown that the difference between the two kinds of moths arose by a random mutation. The key point of randomness is not tested by those data.
Lee SpetnerThe bradys must hold that, on the average, cumulative selection has to add a little information to the genome at each step. But of all the mutations studied since genetics became a science, not a single one has been found that adds a little information. It is not impossible, in principle, for a mutation to add a little information, but it is improbable.
The NDT was an attractive theory. Unfortunately, it is based on the false speculation that many small random mutations could build up to large evolutionary changes.
I am suggesting here that organisms have a built-I capability of adapting to their environment. I am suggesting that to the extent that evolution occurs, it occurs at the level of the organism. This suggestion differs sharply from the thesis of the NDT, which holds that evolution occurs only at the level of the population. Organisms contain within themselves the information that enables them to develop a phenotype adaptive to a variety of environments. The adaptation can occur by a change in the genome through a genetic change triggered by the environment, or it can occur without any genetic change.
Lee SpetnerTags: evolution adaptation neo-darwinism genome environmental-evolution genetic-change phenotypes
There are many examples where species share common plastic traits. What appears to be convergence may just be the plastic response of the organism to its environment. Examples include the following: Limbs that protrude from an animal’s body have more surface area per unit mass than the rest of the body. In cold weather the animal loses more heat per unit mass from these limbs than from other parts of the body. In many species the tails and legs are shorter for those living in colder climates and larger for those in warmer climates. Gulls’ wings are shorter in cold climates than in warm. Hares and foxes also have shorter ears in cold climates than in warm. Eskimos have shorter arms and legs than do people living in warmer climates. . . . Jodan’s rule: Many species of fish tend to have more vertebrae when they live in cold water than do the same species living in warm water. These differences have been shown to depend on the temperature at which the fish have been reared.
What these rules show is not convergence. They show that different species adopt the same anatomical strategies when they have to cope with the same environmental conditions. We have seen that these strategies cannot come from random mutations. It is much more reasonable to say they come from environmental cues acting on the genetic program.
Tags: evolution neo-darwinism convergence jodan-s-rule plastic-traits
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