The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe without Design (1986) is a popular science book by Richard Dawkins. It explains how the cumulative, nonrandom process of natural selection creates complexity. Dawkins develops themes from, and refutes criticisms of, his first book, The Selfish Gene (1976). It was illustrated by Liz Pyle. It won the Los Angeles Times Book Prize for Current Interest and the Heinemann Award. An audiobook was released, read by Dawkins and Lalla Ward. A computer program of the same name was released and it was the basis for a BBC documentary of the same name. The Economist called it "As readable and vigorous a defense of Darwinism as has been published since 1859."
Background The title refers to the watchmaker analogy made by William Paley in Natural Theology or Evidences of the Existence and Attributes of the Deity (1802). Paley posited the complexity of living organisms was evidence of the existence of a divine creator. He argued by analogy with a watch compelling belief in the existence of a watchmaker. Charles Darwin, in On the Origin of Species (1859), argued that cumulative, nonrandom natural selection can create complexity. Dawkins dubs natural selection the blind watchmaker, "blind because it does not plan ahead, does not plan consequences, has no purpose in view. Yet the living results of natural selection overwhelmingly impress us with the illusion of design and planning. The purpose of this book is to resolve this paradox to the satisfaction of the reader."
Synopsis
1. Explaining the Very Improbable Dawkins writes “We animals are the most complicated things in the known universe. … Complicated things, everywhere, deserve a very special kind of explanation." The explanation discovered by Charles Darwin and Alfred Russel Wallace is natural selection. Dawkins emphasizes that is nonrandom (since only adaptive traits are selected for) and cumulative (as adaptive traits accumulate). 2. Good Design Dawkins looks at echolocation as an example of a complex adaptation. When Donald Griffin and Robert Galambos elucidated echolocation in bats, sonar was a secret. But nature invented it independently, to varying degrees. 3. Accumulating Small Change Dawkins looks at the evolution of complexity. He notes that adaptations are too complex to have arisen by chance, and asks: "How then, did they come into existence? The answer, Darwin's answer, is by gradual, step-by-step transformations from simple beginnings. ... Each successive change in the gradual evolutionary process was simple enough, relative to its predecessor, to have arisen by chance. But the whole sequence of cumulative steps constitutes anything but a chance process. ... The cumulative process is directed by non-random survival." Dawkins illustrates random variation coupled with nonrandom selection with his weasel program. He describes his experiences with a more sophisticated computer simulation of artificial selection implemented in the computer program The Blind Watchmaker, which was sold separately as a teaching aid. 4: Making Tracks Through Animal Space Dawkins looks at convergent evolution, starting with the evolution of eyes. Many animals have a patch of light-sensitive cells. "In a continuous series from flat sheet of light-sensitive cells, through shallow cup to deep cup, each step in the series, however small (or large) the step, would be an optical improvement. Now, if you make a cup very deep and turn the sides over, you eventually make a lensless pinhole camera.” Such an eye is seen in the chambered nautilus. The addition of a lens results in the cephalopod eye. "For each of these types of eye, stages corresponding to evolutionary intermediates exist as working eyes among modern animals." In fact, eyes have evolved as many as forty times independently. He returns to echolocation, noting that "Any animal that can hear at all may hear echoes. Blind humans frequently learn to make use of these echoes. A rudimentary version of such a skill in ancestral mammals would have provide ample raw material for natural selection to build upon, leading by gradual degrees to the high perfection of bats." Echolocation has evolved several times independently (in bats, cave swiftlets, oilbirds and cetaceans), another example of convergent evolution. In Australia, many marsupials have evolved to fill the ecological niches occupied by placental mammals on other continents. Similar environments create similar selective pressures, which shape similar adaptations. 5. The power and the archives Dawkins looks at genetics. Gregor Mendel discovered that inheritance is particulate. R. A. Fisher unified Darwin and Mendel in the modern synthesis. 6. Origins and miracles Dawkins looks at the origin of life, including the work of Graham Cairns-Smith. 7. Constructive evolution Dawkins looks at evolutionary arms races between predator and prey, and the Red Queen's hypothesis. Gene duplication is introduced as a means of increasing genetic capacity. When a gene is copied, the new copy can evolve a new function. 8. Explosions and spirals Dawkins looks at Darwin's concept of sexual selection, revived by Fisher. Peacocks evolved colorful plumage to attract peahens. But the peahens, in selecting for plumage, are also passing along genes preferring plumage. This is an example of linkage disequilibrium, which can lead to Fisherian runaway. 9. Puncturing punctualism Dawkins looks at the punctuated equilibrium theory of Niles Eldredge and Stephen Jay Gould. 10. The one true tree of life Dawkins looks at molecular taxonomy and Motoo Kimura's neutral theory of molecular evolution. Neutral mutations serve as molecular clocks that show us when species split. 11. Doomed rivals Dawkins looks alternatives to natural selection, like Lamarckism, and finds them wanting. In an appendix to the 1996 edition, Dawkins explains how his experiences with computer models led him to a greater appreciation of the role of embryological constraints on natural selection. In particular, he recognised that certain patterns of embryological development could lead to the success of a related group of species in filling varied ecological niches, though he emphasised that this should not be confused with group selection. He dubbed this insight the evolution of evolvability.
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