CURRENCIES FOR FORAGING BASED ON ENERGETIC GAIN

We carry out a theoretical investigation of the behavior of a foraging animal that maximizes either the net amount of energy obtained (self- feeding) or the amount of energy delivered to another animal such as i ts young or to a store (provisioning). Using an novel graphical approa ch, we derive general results concerning the effects of constraints on the amount of energy the animal can spend or acquire. In the context of an animal that is provisioning, that is, both feeding itself and de livering energy to a given location, we establish a general relationsh ip between the beat Foraging option when feeding itself and the best o ption to use when delivering energy. Our results extend and unify prev ious results in this area.