Behavior is the way that animals act. For example, how do they get food or take care of their young? How do they find a place to live in or __________ (1) themselves from danger? Much behavior is innate; that is, animals are born with it. __________ (2), animals learn much other behavior. There are several kinds of learned behavior. One simple __________ (3) of learned behavior is habituation. This happens when an animal learns to feel comfortable in a new __________ (4) and doesn't pay attention to it anymore. For example, young horses are often afraid of noisy streets. But after a while, they learn to pay no attention to the normal __________ (5) and sounds of a city. Another kind of learned behavior is conditioning. It is a way of learning by association — that is, by putting __________ (6) different ideas. In 1900, Ivan Pavlov, a Russian biologist, studied conditioning in dogs. Dogs innately salivate (produce liquid in the mouth) when they smell food. Pavlov __________ (7) a bell every time he gave food to a dog. Soon the dog started to __________ (8) the sound of the bell with the smell of food. After some time, it salivated when it heard a bell alone, __________ (9) food. Learning is important for all animals in a new __________ (10). It allows an animal to be adaptable — that is, able to change in a new situation. without responded associate However rang aside type defend environment Anyway sights together situation way protect