This is a very interesting guest post at Remote Central:
All species vary through time and space. You don’t necessarily look the same as any one of your ancestors. Therefore “like begets like” but each individual can be a bit different. It is impossible for a sperm whale to evolve from a bowl of petunias, or a duck from a dandelion, as some creationist and Intelligent Design supporters accuse evolutionists of believing. But over time it is possible for a cow to evolve from something like a camel, or a human to evolve from something like an ape. Evolution doesn’t proceed in a straight line though, especially not a straight line with a human at the end.