Chapter 18: Animal Behaviour (Learning (Imprinting (Bonding: Usually…
Chapter 18: Animal Behaviour
How an animal responds to changes in its internal or external environment.
Important for an organism's survival + successful production of offspring.
: The study of connection between behaviour and evolutionary origins.
Types of behaviour
Inborn --> Like reflexes --> Responses for the purpose of survival or safety. E.g. running away/ loud noises.
Studies of honeybee communication and waggle dance.
Fixed action pattern.
Fixed action pattern
Innate behaviour that once begun, will continue to the end no matter how useless.
Initiated by an external
Stimuli become releasers when the stimuli are exchanged between members of the same species.
E.g. stickleback will only attack a male invading their territory if a red underbelly in the invader can be seen.
Where the responses of the organism are modified by experience.
Capacity to learn is limited by lifespan and complexity of the brain.
Shorter life span (e.g. fruit fly) = less time to learn = more dependant on fixed action pattern.
Longer life span + more complex brain = behaviour more dependant on learning from prior experiences.
Simplest form of learning.
After being stimulated for a while, an organism
gets used to (habituated)
with the stimulus and begins to
E.g. a hydra shrinks if touched, but will ignore it after a while.
When one stimulus becomes linked to another through experience.
Associative type of learning.
trained dogs to salivate at the sound of a bell rather than just with food.
Trial and error learning. Also associative type of learning.
Associate one of its behaviours with
trained rats to press levers at will to be rewarded with food.
: Usually between mother and offspring.
Case study: Geese hatchlings will follow the first thing they see move.
For animals who depend on parental care, imprinting is critical to the offspring's
survival + development
Occurs during a
sensitive or critical period
of an individual.
At the end of the juvenile period, the
response goes away
Any kind of behaviour that involves
interaction between 2+ animals
, usually of the
A behaviour that is more
successful when carried out in groups
than it is individually.
E.g. lions that hunt in packs can bring down larger animals than they could hunting alone.
involving threats or combat to
Usually over food, mates, or shelter.
Aggressive behaviour could be real, ritual, or symbolic.
Symbolic usually prevents serious harm. The aggressor will simply threaten the individual, but doesn't have to kill him.
E.g. Dogs do this by baring teeth, erecting hairs, stand upright and look at opponent directly.
Opponent backs off with
like looking away or running away.
After settling a dispute, future encounters between the same individuals usually won't involve more combat or posturing.
Pecking order behaviours
that dictate the
of an animal in their group.
Controls behaviour of all the rest
. Usually assured the
first choice of any resource
, including food, territory, and mates.
Beta animal: Controls behaviour of all except the alpha.
An area that other members of the community are
Used for hunting, mating, raising young.
Size varies with function and no. of resources available.
A behaviour that
decreases an individuals reproductive fitness
(or causes death), but
increases the fitness of its group/ family
E.g. a worker bee can sting to defend its hive but will die. Meanwhile, the queen be is safe and can lay her eggs.
Altruism evolves by
, where the no. of copied genes in a related group increases.
of the individual that sacrificed will share
of the altruistic behaviour and can
pass on their genes