Animal behavior

How do we study it?

How do we classify it?

The science of animal behavior

How do animals behave?proximate causationwhat physiological mechanisms enable this

Why do they behave as they do?ultimate causationevolutionary origin and purpose of thebehavior

These areas of study may not overlap much

Many approaches to the study of animal behavior

Comparative psychologyare there general laws of behavior?

originally studied by inference

later: controlled experimentsrats, pigeons, dogs, primates

Out of context; no evolutionary perspective

Ethology: study of animal behavior in itsnatural habitat

Founders: Konrad Lorenz, Karl von Frisch,Niko Tinbergen

Techniques:field observationusing natural variables but manipulating

themperforming laboratory experimentsbut comparing results with natural ones

Insights:behavioral traits can be measured

behaviors have evolutionary histories

Sociobiology (E.O. Wilson. 1970s)social behavior is reciprocal, cooperativeorganisms depend on each other

Examples:colonial vertebratessocial insectsmammals such as dolphins and elephantshumans

Controversial: to what extent is humanculture biologically determined?

All of the above approaches can be appliedto behavioral ecology (patterns will befavored that promote survival andreproductive success)

Song repertoireCost-benefit analysis of foraging

How do you describe behavior?

1930s egg-rolling in greylag goose

Sequence was carried out to completionregardless

Stereotypical behaviorreleaser (triggering stimulus)

sign stimulus

Seen even when inappropriate

What happened:male stickleback is territorialbelly becomes red; male will becomeaggressive against another red-bellied male

Tinbergen: males reacted to red objects in theirenvironment

Made models with and without red undersides

English robins react the same way

Costs and benefits of such behaior?

FAP (fixed action pattern)

May be “expensive” if activated incorrectly

Otherwise may be the most efficient way ofdoing things

Are these behaviors innate?no teaching necessaryappear suddenly and are as successful asbehavior in older animals

How to account for environment?

When is learning appropriate? (modifying behavior due to past experiences)

Learning vs (neurological) maturation

Habituation as a form of learning

Loss of response to stimuli that are not helpful

Many examples, e.g., aquatic snail Aplysia(Kandel et al.)

Some neural pathways became less active

New neural pathways may also be formed,or can change

Imprintingis time sensitiveis usually irreversible

usually very reliable

Social behavior

What do we mean by social behavior (inter-action between one member of a speciesan another of the same species)

Groups may respond to the same environmentalsignal (light, temperature, etc.)

Social aggregations; animals signal to each other

What are some examples of social interaction?

Breeding (may be the extent of it for some animals!)

Defense

Finding food

Division of labor

Parent-child interactionslearning

Japanese macaques

One female started washing sand off of sweet potatoes

Others imitated her; they later taught theiroffspring to do so. She later learned to dothis with grain.

Her peers imitated her; the older males did not!

Any disadvantages to social living?

Depends on the circumstances

May need more room

May be safer when dispersed

Aggression and dominance

Cooperativity and competition

Many animals have ritualized ways of showingaggression, submission, etc.

Sometimes the roles are not as clear-cut, sodominant animals are challenged

Territoriality

Against “intruders” of the same species

Crustaceans, insects, fishes, amphibians,lizards, birds, mammals(are humans territorial?)