Forelimbs 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 GouldIf genius has any common denominator, I would propose breadth of interest and the ability to construct fruitful analogies between fields.
Stephen Jay GouldRecapitulation provided a convenient focus for the persuasive racism of white scientists; they looked to the activities of their own children for comparison with normal adult behavior in lower races.
Stephen Jay GouldPeople are storytelling creatures. We like stories that go somewhere, and therefore we like trends - because trends are things that either get better or get worse, so we can either rejoice or lament. But we mistakenly depict many things as trends moving in some direction. We take the "full house" of variation in a system and try to represent it as a single number, when in fact what we should be doing is studying the variation as it expands and contracts. If you look at the history of the variation in all its complexity, then you see there's no trend.
Stephen Jay Gould