The notion of rationality is much discussed by both Economists and Philosophers. Perhaps you are rational if you accept certain axioms of rationality. If you prefer A to B and B to C then you must prefer A to C. Or you can define rationality in terms of the net results of your behavior. We examine a notion of algorithmic rationality. Even animals upwards from the humble tick carry out algorithms. Are they rational? And can we use this theory to define the IQ of animals?