Orchids manufacture their intricate devices from the common components of ordinary flowers, parts usually fitted for very different functions. If God had designed a beautiful machine to reflect his wisdom and power, surely he would not have used a collection of parts generally fashioned for other purposes. Orchids were not made by an ideal engineer; they are jury-rigged from a limited set of available components. Thus, they must have evolved from ordinary flowers.
Stephen Jay GouldEvolution has encountered no intellectual trouble; no new arguments have been offered. Creationism is a home-grown phenomenon of American sociocultural history-a splinter movement ... who believe that every word in the Bible must be literally true, whatever such a claim might mean.
Stephen Jay GouldLife shows no trend to complexity in the usual sense-only an asymmetrical expansion of diversity around a starting point constrained to be simple.
Stephen Jay GouldPrecise adaptation, with each part finely honed to perform a definite function in an optimal way, can only lead to blind alleys, dead ends, and extinction.
Stephen Jay GouldForelimbs of people, porpoises, bats and horses provide the classic example of homology in most textbooks. They look different, and do different things, but are built of the same bones. No engineer, starting from scratch each time, would have built such disparate structures from the same parts.
Stephen Jay GouldDarwin's principle of natural selection leads to the prediction that the proper way to analyze any evolutionary development is to see the new features as adaptive to environments. And that's a perfectly good principle. The problem is that there are many evolutionary biologists who view everything that happens in evolution as directly evolved for adaptive benefit. And that just doesn't work. Whenever you build a structure for adaptive reasons, the structure is going to exhibit properties that have nothing to do with adaptation. They're just side consequences.
Stephen Jay Gould