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 learning
1. Operant Conditioning
2. Imprinting
Operant Conditioning
• Def: the gradual strengthening of stimulusresponse 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
Female Choice
• 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 Ex…
Female Choice Ex…
• Bowerbird
– Female chooses male by his collection of
objects, not plumage.
Male Competition
• Males competing with other males to mate
with a female.
Communicative Behavior
1.
2.
3.
4.
Chemical Communication
Auditory Communication
Visual Communication
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.
Altruism Ex’s:
• Birds
– Weavers, Crows, Canada Goose, etc.
Altruism Ex’s:
• Mammals:
– Meerkat, Naked-Mole rat, Primates, etc.