To imply that evolutionary theory should be subject to the same level of doubt or debate as speculations on the magnitude and speed of global climatic changes, or the sociological and ethical implications of molecular technology is a spurious argument. Climate change is a broad, multidisciplinary hypothesis, whereas evolutionary theory is an organizing principle.

To deny evolution is to deny that living things change, which is not rational. Pests evolve resistance to pesticides and bacteria evolve resistance to antibiotics. To deny organic change is no different from denying that the earth goes round the sun. The fact that species change from generation to generation is not in question -- the exact mechanisms responsible for such changes are.

The Browns resort to the tired old claim of religious fundamentalists that evolution implies a belief in "naturalistic atheism" and is therefore no different from a religion. Nothing could be further from the truth. Just because science operates perfectly well without any need for divine intervention or teleology (the idea that everything has a predetermined purpose) does not imply that scientists must abandon belief in divinity or divine purposes.

Many do, but many do not. Rather, science requires proof of process -- a hypothesis that is both testable and falsifiable. Creationism is not a scientific explanation of anything because it can be neither tested, nor falsified. The larger framework of evolutionary biology is constantly being tested, falsified (in specific details) and improved, so it actually "evolves" the same as the very living things it describes.

In contrast, creationism stands as immutable dogma, suffering constant erosion by the forces of reason without being able to respond to any challenges beyond the simplistic assertion "God did it." The inadequacies of creationism -- its inability to account for change in living things, accommodate new evidence, or generate new understanding -- have long ago sidelined it from any serious scientific consideration. Evolutionary theory does not fear creationism or its new incarnation (un)intelligent design -- it is creationism that fears evolutionary theory, for it is intellectually stagnant, unable to account for its own inconsistencies with physical evidence or evolve into anything better.

The theories of natural selection (which creationists tend to erroneously equate to evolutionary theory as a whole) and sexual selection are two mechanisms proposed by Darwin to explain specific phenomena arising from evolution which, in itself, is not a theory at all, but merely a general term for the various processes of organic change. However, Darwin's two theories have been well-supported by empirical evidence and dozens of new evolutionary theories have since been advanced that build on earlier ones and improve our understanding of other mechanisms of organic change. These understandings continuously help us to better manage our ecosystems and harvest their abundance in sustainable ways.

The Browns contend that freedom of academic speech will strengthen our country. I agree. But just as freedom of speech can be abused to spread racism or prejudice, so it also has the potential for abuse if used to undermine or erode scientific principles that happen to conflict with religious agendas. If this kind of abuse receives the blessing of our education system, our children will have more than freedom of speech, they will have freedom of ignorance.