Handedness
Many other animals also have handedness. For example: elephants often have preferences for whether they swing their trunks to the left or the right. Honeybees have right antennas that are more sensitive to smells. Parrots can be left- or right-footed, and some don’t mind (they are ambidextrous). Animals as different as chickens and minnows like to look for food with one eye and look out for predators  with the other. This seems to help them do two things at once.