Chapter 35: Animal Behavior Section 1: Elements of Behavior

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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