All butterflies have a four-part life cycle, which includes egg, larva (or caterpillar), pupa (or chrysalis) and adult. The egg stage is usually short-lived. In most local species the egg hatches one to two weeks after being laid. Only a few local species overwinter in the egg stage. The larvae are feeding machines. All local butterfly larvae feed on plant parts, which may include leaves, flowers, or fruits. Most species are quite host specific, and will feed only on a small selection of related plants, sometimes just a single species. Larvae often have elaborate means of protecting themselves, including camouflage, defensive chemicals, or construction of shelters using silk and leaves. When a larva has completed its task of feeding and growing, it often wanders a short distance and finds a hiding place before becoming a pupa. Pupae can wiggle, but are unable to move around and are usually attached to a substrate. The adult butterflies emerge from the pupae and must stretch and dry their wings before they can fly. Males usually emerge first, and spend their time searching for females. Some species hold territories and defend them from other males. Females are less active than males and spend their time looking for suitable egg-laying sites. Most butterfly species feed on nectar from flowers. Some species may prefer other sources of nutrients and energy, including tree sap, rotten fruit, animal droppings, or carrion. Depending on the species, the lifespan of the adult butterflies may range from only a week to several months. A few local species even pass the winter hibernating as adults.