An interesting paper has appeared that shows that a gene present in most vertebrates is absent in snakes. The gene is responsible for the production of the unpronounceable peptide ghrelin. Discovered in 1999, ghrelin is produced by a number of organs in the body and has a multitude of actions, sometimes acting as a true hormone via circulation in the blood and sometimes, it would seem, locally on cells in close proximity. The main source of ghrelin is the lining of the stomach and a major...