'Evolution is a myth." That's how Delaware's GOP Senate candidate Christine O'Donnell felt 12 years ago as captured on comic Bill Maher's television show.
Maher recently retelecast a tape of O'Donnell's remarks, in which she expanded on her critique, asking if evolution were true, "why aren't monkeys still evolving into humans?" Her campaign last week did not say if her views had changed.
Though many guffawed at her expense, biologists say her question reflects one of the most pervasive and common public misconceptions about evolution.
Her error wasn't in tying us to monkeys instead of apes. The question would be equally misguided either way.
"People mistake evolution as something progressive - that things continue to get better and move more and more towards us," said Swarthmore College biologist Scott Gilbert.
Images from popular culture reinforce the misconception, he said. One of his favorites is a magazine ad showing a protozoan, then a slug, then a snail, a butterfly, a fish, and so on. Since it was an ad for Continental Bank, the pinnacle was a white male banker, he said.
Darwinian evolution doesn't work that way. Instead, different organisms have branched off from one another and evolved in many directions. Evolution is not a ladder, Gilbert said, but a tree - or more accurately, a bush. "Which direction is considered better depends on your perspective," he said. "If textbooks were written by birds, they'd say mammals were beakless animals that can't fly."
Gilbert said the tree idea has an analogy in religion since new faiths can branch off from ancestral ones. The answer to why there are still monkeys, or apes, is the same as that given to the question Why are there still Catholics?
"We all know that Protestantism evolved from Catholicism. We have Luther's Ninety-Five Theses and Henry VIII's Act of Supremacy," said Gilbert, who also has a degree in religion.
"The answer is that evolution, whether of religions, organisms, or automobiles, does not form a linear chain."
The notion of an evolutionary chain or ladder predates Darwin's 1859 publication of On the Origin of Species, said Michael Weisberg, a University of Pennsylvania philosopher of science. One of the most detailed versions was laid out in the early 19th century by French naturalist Jean-Baptiste Lamarck.
Lamarck is best known for his discredited idea that animals can pass down acquired traits. But he also came up with a completely discredited theory of evolution, Weisberg said.
In Lamarck's view, each living creature came from a separate spontaneous origin of life and progressed through a great chain of being, taking on ever more complex forms, culminating in the French.
French people, according to Lamarck, evolved from other kinds of people, these having evolved from apes, then monkeys, and before that, other animals - dogs, fish, and down to creatures he deemed yet less complex.
The difference between the French and contemporary monkeys, the theory went, was that the French started evolving before the monkeys did. So, in theory, monkeys would slowly evolve into French people.
Mais non!
Even after Darwin, the old ladder-of-progress idea remained so pervasive that Stephen Jay Gould devoted a whole chapter of his book Wonderful Life to correcting it. "The familiar iconographies of evolution are all directed toward reaffirming a comfortable image of humans as inevitable and superior."
Instead, in Gould's view, humans are no more inevitable than bats or ostriches.
In the currently accepted "bush" of evolution, humans did evolve from now-extinct apes, which themselves evolved from a now-extinct species of monkey, said Blair Hedges, a Penn State evolutionary biologist.
So technically it's not wrong to say we evolved from monkeys - though our monkey ancestors are more distant than our ape ancestors. Looking back even further, we can also say we evolved from fish, as did all land vertebrates.
But just as some Catholics stayed Catholics after the Reformation, some fish stayed in the water. Those fish continued to evolve into myriad new species. None of them show any sign of becoming human.