Download Animal Behavior

Animal Behavior
Animal Behavior: An Overview
Ethology is the study of animal behavior
 Behavior is everything an animal does and
how it does it

Nature vs. Nurture
In biology, it’s not an either/or scenario
 Both genes and environment affect animal
behavior

Innate vs. Learned Behaviors

Innate behavior is developmentally fixed,
regardless of the environment
This is INSTINCT
 Examples:

• Kangaroo rat jumping at the sound of a
rattlesnake, even if it has never heard a snake
before
• Humans using their voices to communicate
Innate Behavior –
Fixed Action Patterns

An FAP is a sequence of
unlearned behavioral
acts that is essentially
unchangeable and, once
started, is usually carried
to completion


Triggered by a sign
stimulus
Example:


Aggressive behavior in
male stickleback fish in
response to the red
underside of an intruder
fish
Yawning in humans
Innate vs. Learned Behaviors

Learned behavior is the modification of behavior
based on experience

Habituation: loss of responsiveness to stimuli that
convey little or no information
• “crying wolf”

Associative learning is the ability of many animals to
associate one feature of the environment with another
• Classical Conditioning
• an arbitrary stimulus is associated with a reward or punishment
• Pavlov’s Experiment
• Operant Conditioning
• Using consequences to modify behavior
• Mouse eating distateful caterpillar
Altruism & Inclusive Fitness


Most social behaviors are selfish
Altruism =



When an animal behaves in a way
that reduces its individual fitness
but increases the fitness of the
other individuals in the population
Example: squirrels, worker bees
Helps close relatives (children,
siblings, etc.), thereby increasing
the individual’s genetic
representation in the next
generation – “inclusive fitness”
Animal Signals & Communication


A signal is a behavior that causes a change in
another animal’s behavior
Communication involves the transmission of,
reception of, and response to signals between
animals

Chemical Communication:
• Pheromones – particularly important in reproductive
behavior

Auditory Communication:
• Drosophila males produce a characteristic “song” by
beating their wings
Kinesis vs. Taxis

Kinesis
 An increase or decrease in movement in response to an
environmental stimulus
 NONDIRECTIONAL
 Examples:
• As the humidity increases, wood lice move less
• Pillbugs live best in moist conditions; they move around more in dry
areas and less in moist/humid areas
• WHY???
• More movement increases likelihood they will encounter a moist area

Taxis
 A movement towards or away from a stimulus
 DIRECTIONAL
 Examples:
• Fish swimming against the current
• Bacteria swimming towards light