How small is the difference between people?
"In fact, genetically, we are among the most similar at all species. Only one out of every 1000 nucleotides that make up our genetic code is different. One individual, um, another. These look like penguins have twice the amount of genetic difference. One from the other than humans. And these fruit flies, ten times more difference. Any to fruit flies maybe as different genetically from each other as a human is from a chimpanzee."