Chapter 35: Animal Behavior

1. Chapter 35: Animal Behavior Section 1: Elements of Behavior

2. Behavior and Survival • The behavior of an animal is just as important to its survival and reproduction as any of its physical characteristics • For that reason, animal behaviors have evolved in many different ways, just as animal physical characteristics have • Behavior is in an organism’s genetic makeup • Behaviors can enhance an animal’s ability to survive

3. Behavior and Survival • There are some behaviors that animals must perform automatically in order to survive • “Know” how to hunt soon after they are born • Dolphins must know in advance that they have to hold their breath under water • Other behaviors must be more flexible and capable of being changed by experience • Hummingbirds must learn to find food in different kinds of flowers at different times of the year

4. Behavior and Survival • A variety of automatic and flexible behaviors exist in the animal kingdom • Instinct • Learning

5. Instincts • Instincts are behaviors that can be called inborn • Instincts are built into an animal’s nervous system and cannot be changed during the animal’s lifetime, even by learned experiences • Instinctive behaviors are genetically controlled • Many instinctive behaviors consist of actions that always continue in a certain order once they have begun

6. Instincts • Although some instinctive behaviors are relatively simple, others can be very complex • Web-building behavior in spiders • Courtship behaviors in insects, fish, birds, and mammals

7. Learning • Learned behaviors are shaped by experience • Learning is the way animals change their behavior as a result of experience • Learning is valuable to an animal because it may enhance the animal’s chances of survival and its chances of reproduction and passing on its genes to another generation

8. Learning • There are several different ways in which animals learn • Habituation • Classical conditioning • Operant conditioning • Insight learning

9. Learning • Habituation is a decrease in response to a stimulus that neither rewards nor harms an animal • One of the simplest ways in which animals learn • EXAMPLE • Very young ducks and geese are frightened of any shadow that moves overhead • Within a few days of hatching, however, the young birds find that some shadows moving overhead – the shadows of adult geese and ducks – mean nothing • They soon habituate to these shadows and no longer try to escape from them

10. Learning • Classical conditioning occurs when an animal makes a mental connection between a stimulus and some kid of good or bad event • Pavlov’s dogs • Operant conditioning is sometimes called trial-and-error learning • An animal learns to behave in a certain way in order to receive a reward or avoid punishment • EXAMPLE • A predator learns not to eat a particular prey in order to avoid an unpleasant experience

11. Learning • In insight learning, an animal applies something it has already learned to a new situation – without a period of trial-and-error • Rare among most animals • Common only in primates

12. Instinct and Learning Combined • Some behaviors cannot occur without some learning on the part of the animal • For example, newborn ducks and geese have a built-in urge to follow their mother • But this instinct to follow does not include a picture of what their mother looks like • This picture must be provided by experience in a process called imprinting • The newborn bird will follow the first large slowly moving object it sees

13. Chapter 35: Animal Behavior Section 2: Communication: Signals for Survival

14. Communication: Signals for Survival • Any time animal behavior involves more than one individual, some form of communication is involved • Communication is the passing of information from one animal to another • Animals use many varied techniques to communicate with one another

15. Sensing the Natural World • No two animal species sense the world in the same way • Each animal species has a unique way of gathering and transmitting information • Understanding the differences between our sensory world and that of animals is important in the study of animal behavior • Today, many scientists study animals under natural conditions • Ethologists

16. Why Animals Communicate • Animals communicate with one another for a variety of reasons • Courtship behavior • Food • Potential dangers

17. How Animals Communicate • Animals communicate with other members of their species and with other species • The ways in which they communicate are limited only by the kinds of stimuli their senses can detect • Visual signals • Movement and color • Sound signals • Chemical signals • Well-developed sense of smell • Produce special chemicals called pheromones that transmit information • Electrical signals

18. Language • Some forms of animal communication are more complicated than any of the signals just described • Animal “dances” • Human language is the most complicated form of communication

19. Chapter 35: Animal Behavior Section 3: The Evolution of Behavior

20. The Evolution of Behavior • The physical structures in organisms develop according to a program contained in their DNA • Different characteristics are coded in different genes or groups of genes • Variations in these genes lead to inheritable variations in the characteristics of the animals that carry them

21. The Evolution of Behavior • Genes code for behaviors as well as for physical characteristics • Evidence for genetic control of behavior can be demonstrated by crossing closely related animals that show different behaviors • The evolutionary fitness of an individual is increased if it forms some type of social group with others of its kind