Haemoglobin is a very large molecule by ordinary standards, containing about ten thousand atoms, but the chances are that your haemoglobin and mine are identical, and significantly different from that of a pig or horse. You may be impressed by how much human beings differ from one another, but if you were to look into the fine details of the molecules of which they are constructed, you would be astonished by their similarity.
Francis CrickThe major credit I think Jim and I deserve is for selecting the right problem and sticking to it. It's true that by blundering about we stumbled on gold, but the fact remains that we were looking for gold.
Francis CrickThis seems highly likely, especially as it has been shown that in several systems mutations affecting the same amino acid are extremely near together on the genetic map.
Francis CrickBiologists must constantly keep in mind that what they see was not designed, but rather evolved.
Francis Crick