Unit Animal Science

Problem Area Growth and Development of Animals

Lesson Peck Order of Chicks

Student Learning Objectives 1. Discuss the importance of observing animals in a controlled setting. 2. Identify particular animal behavior and understand the importance of inbred behaviors. 3. Understand the effects of personality and size difference in animal behavior.

Terms Alpha animal Controlled Dominant Innate Learned Peck order Submissive

In terms of laboratory experiments, why is it important to observe animals in a controlled setting? Laboratory animals used in experiments must be observed in a controlled setting. A. Controlled is a term that means unchanging. To correctly observe and make conclusions about an experimental variable, the environment of the animal must be constant for each animal or each observation of the behavior. B. Without proper environmental control, there is no assurance that the behavior was not the result of an environmental factor, instead of the experimental variable.

C. Ways to control the setting or environment of an experimental animal could be:  1. Isolate the animal from others for the duration of the experiment.  2. Move the animal to a controlled setting for the duration of observation for the experiment.  3. Isolate a group of animals not only during observation, but also when not being observed or experimented on. D. It is important to remember that animals should be observed in a setting where they would most likely live.

How do we look for and observe a particular behavior in animals and what is the importance of inbred behaviors? A. The peck order, or flock hierarchy, is established when each bird in the flock has had an aggressive interaction with every other bird in the flock. B. Peck order, like many other animal behaviors, is an innate behavior, meaning the animal is born with the instinct to behave in that manner. Inbred behaviors are important to give the animal basic instinctive survival skills to compete for food and survive in nature. Nest building in sows is an innate behavior.

C. Behavior in animals can be learned as well as innate. Learned behaviors are ones that the animal was not born with, but learned over time. Pavlov’s dog experiment caused dogs to salivate at the sound of a bell because they associated the bell with being fed. Eventually, the dogs would salivate when they heard the bell, whether there was food present or not. This is an example of a learned behavior, known as association, in animals.

What effect does personality and size difference have in animal behavior? Much of an animal’s behavior is influenced by territory and intrusion into territory by another animal. A. Dominant, or more socially aggressive birds are usually found at the top of the social hierarchy of the flock. Submissive, or socially shy birds are usually found at the bottom of the flock hierarchy.

B. The top bird in the flock is referred to as the alpha animal. C. Animals that are highest ranked in the peck order generally get first chance at feed and therefore are the healthiest birds in the flock. Once rank is established, the birds will fight less and have more time to spend eating. Stress levels also decrease with higher positions in the hierarchy. Overall, the higher the rank of the bird, the healthier the bird will be overall.

Review/Summary In terms of laboratory experiments, why is it important to observe animals in a controlled setting? How do we look for and observe a particular behavior in animals and what is the importance of inbred behaviors? What effect does personality and size difference have in animal behavior?