What is behavior? An observable, coordinated response to

an environmental stimulus

Behavior can be seen in all Kingdoms; Plants can respond to a change in light by

growing in a different directionFungi respond to limited resources by

producing sporesBacteria can move towards a source of

carbon dioxide

Are behaviors genetically based? Genes code for proteins – how may

proteins relate to behaviors?

Protein Receptors

Proteins on the surface of cells interact with the environment in a number of ways. Photoreceptors – produce a chemical

response to lightThigmoreceptors – usually attached to a

cilia, produce chemical response to touch or movement.

Chemoreceptors – produce a chemical response to a chemical stimulus

Animals

Have organs like eyes and ears made up of specialized cells with these protein receptors.

These organs are integrated with the rest of the body by the nervous and endocrine (hormone) system.

Instincts Certain stimuli – called “sign stimuli”

cause the same response, regardless of how many times the organism experiences the stimulus.

These responses that occur without learning are called INSTINCTS.

Generally, the response that is produced is called a FIXED-ACTION PATTERN. This is a response that requires no feedback from the environment.

Examples of Instincts

All Mammals (including humans) – Suckling – the response to a nipple by a

newborn

Cats – burying their waste

Learned Behavior Learning is unique to animals Learning is when a behavior is changed as

a result of processing and integrating experiences from the environment.

Types of Learned Behaviors Imprinting – described by Konrad

Lorenz; a time-dependent learning triggered by the exposure of sign stimuli during a sensitive period when the animal is young.

Classical Conditioning

Described by Ivan Pavlov; the association of a novel stimulus with something that will cause an instinctual response.

Pavlov’s dogs were taught to salivate at the sound of a bell by ringing a bell every time they were presented with food. Eventually the food was removed but salivation still occurred.

Operant Conditioning

An animal learns to associate a voluntary activity with its consequences.

Communication Communication is a combination of

instinctual and learned behaviors. You have the ability to communicate with facial expressions as a newborn, but you must learn language.

Types of Displays

Threat display – unambiguous announcement that a signaler is planning on attacking.

Courtship Display A ritualized display, often based on

behaviors valued by the species (nest making, strength, etc), that are used to attract a mate.

Tactile Display A signaler touches the receiver in a

ritualized way.

Evolutionary Basis of Behavior Many behaviors increase the individual’s

chance of surviving. One type that is difficult to understand is Altruistic behavior. Self-sacrificing behavior for the benefit of

others despite lowering the likelihood of one’s own reproductive success.