Animal Behavior

Chapter 29

What is Behavior??

• Behavior – observable and coordinated responses to environmental stimuli

• Genetic or Learned or Both???– “Nature or Nurture”– How do you explain the behavior differences

with twins?

Learned Behavior

• Learning = a durable change in behavior brought about by experience.

– Occurs when a behavior changes with practice.

• Two forms of learning1. Operant Conditioning

2. Imprinting

Operant Conditioning

• Def: the gradual strengthening of stimulus-response connections.

• Teach a dog tricks by giving a treat or praise

Imprinting

• Def: a learning process in early life whereby species specific patterns of behavior are established

• Best known with birds being imprinted on the first thing they see when they hatch mother.– Purposes:

• Keeps babies near mother

• Also causes males to court same species later in life.

Adaptive Learning

• Behavior can evolve!– Changes because of environment

• Abiotic

• Biotic: usually other organism (diff. sex)

• Sexual Selection…

• Sexual Selection: changes in females and males, often due to differential reproductive success of individuals, caused by mate choice and competition for mates.

• Types:– Female choice– Male competition

Female Choice

• Courtship Displays: rituals that serve to prepare the sexes for mating.– Male usually displays,– Female chooses the male with best display

• Good Genes Hypothesis

• Run-away Hypothesis

• Good Genes Hypothesis– Females benefit by having a male with good

genes• Able to pass on those genes to the offspring

• Enabling the offspring to live longer.

Female Choice

• Run-away Hypothesis– Females choose mates on the basis of traits that

make them attractive to females.– “Run-away” means that this causes the males to

have exaggerated traits to out compete other males.

– Problem: could cost male his life.

Female Choice

Female Choice Ex…

• Bowerbird– Female chooses male by his collection of

objects, not plumage.

Female Choice Ex…

Male Competition

• Males competing with other males to mate with a female.

Communicative Behavior

1. Chemical Communication

2. Auditory Communication

3. Visual Communication

4. Tactile Communication

Chemical Communication

• Works with distance, night, and day.

• With Pheromone – within same species

• Insects – captured by antennae

• Mammals – smell

• Yes, humans have pheromones

Auditory Communication

• Sound

• Faster than chemical, travels farther, effective both day and night.

Visual Communication• Sight

• Usually used by organisms that are active during the day.

• Used between males as threat postures, etc.

• Bird plumage for courtship

• Bright mouths on chicks – ‘feed me’

Tactile Communication

• Touch

• Ex:– Primates groom one another– Chicks peck the mothers beak– Honeybees communicate (‘waggle dance’)

Group Living

• Advantages:– Avoid predators– Help rearing offspring– Gathering food

• Disadvantages:– Hierarchies– Illness– Share food

Altruism

• Behavior that involves a reduction in direct fitness that may be compensated by an increase in indirect fitness.

• Sentinel - the individual that watches for danger and warns the group.

Altruism Ex’s:

• Insects– Bees, Ants, Termites, etc.

• Birds– Weavers, Crows, Canada Goose, etc.

Altruism Ex’s:

Altruism Ex’s:

• Mammals:– Meerkat, Naked-Mole rat, Primates, etc.