Behavioral Biology – also known as Animal Behavior
Chapter 34: Elements of Behavior
Outline
Behavior: what an animal does and how it does it. How an organism reacts to a
stimulus, a change in its internal condition or external environment.
- One specific reaction is called a response; a group of responses interacting is
generally called behavior.
- Different body systems interact to produce a behavior (frog uses its ears to hear
and its brain, muscles and eyes to leap….)
- Includes invisible processes like learning and memory.
- Animals with simple nervous systems respond to stimuli with simple behaviors; - Animals with complex nervous systems react with complex and precise behaviors.
I. Innate vs. Learned Behavior
A. Innate Behavior - also called instinct; developmentally fixed (unaffected by
environment)
1. Innate behavior is fully functional from the first time it is performed
2. Examples: newborn suckling, building nests, baby birds raise heads and
open mouths and cheep when parent lands on side of nest
3. How did innate behavior evolve? Some behaviors are so important that the
animal has to get it right on the first try in order to survive. Those that did
not failed to leave any offspring…..
4. Kinesis – non-directional movement in response to a stimulus (for
example, pill bugs move faster in dry or bright areas; not trying to find moist,
dark areas but that is the result)
5. Taxis – directional movement toward or away from stimulus. Many kinds
of taxis depending of the stimulus causing the taxis (chemotaxis, gravitaxis,
phototaxis, magnetotaxis, etc…..)
B. Learned Behavior – also called acquired behavior; behavior that changes as a
result of experience. Develop over time. 4 major types: habituation, classical
conditioning, operant conditioning, insight learning
1. Habituation – process by which an animal decreases or stops its response
to a repetitive stimulus. (example: shore ragworm and shadow, p. 874)
2. Classical Conditioning – process by which an animal connects a stimulus
to a reward or punishment (example: dog and bell (food; Pavlov’s dogs); dog
and skunk (unpleasant smell), p. 874)
3. Operant Conditioning – also called trial and error learning.; process by
which an animal learns a behavior through practice. (example: Skinner’s box,
p. 875)
4. Insight Learning – most complicated! Applying learning to a new
situation. Common in humans and primates. Have to really think!
C. Instinct and Learning Combined
1. Most behaviors are a result of both these behaviors.
2. Imprinting. Some baby animals instinctively follow the first moving
object they see, usually their mother. It helps keep them close ot their mother and
helps them find food. They are born with this instinct, but with no knowledge of
what their mother will look like. For example, in the movie Fly Away Home the baby
geese imprinted on an airplane… And baby salmon imprint on the odor of the
stream in which they were born. They head out to sea and then years later use their
sense of smell to navigate them back to their home stream to spawn (release their
eggs or sperm into the water).
II. Complex Behavior Patterns
A. Behavior Cycles - cycles in behavior in response to cycles in environment.
Circadian rhythm in response to day and night, migration cycles in response
to seasons.
B. Courtship – behavior related to reproduction and reproductive strategy.
(intrasexual competition, intersexual choice, courtship rituals…)
C. Social Behavior - animals that live in groups interact closely and often
cooperate. Because they share a large proportion of each other’s genes, they
often cooperate closely.
a. Sometimes make sacrifices for the group or for one member of the
group – this is called altruism.
b. Primates form some of the most complex social groups.
D. Competition – when 2 animals claim a limited resource, the result is
competition.
a. Territoriality is an example of this – territories contain resources
such as food, water, nesting sites, shelter, and/or mates.
E. Communication – the passing of information from one animal to another (or
others)
a. Visual Signals – using movement and color to communicate with
another animal. (Cuttlefish changes color and patterning for many
purposes – p. 881)
b. Chemical Signals – Animals with a strong sense of smell
communicate with chemicals. This includes many insects, fish and
mammals.
i. Pheromones are chemical messengers that affect behavior of
other individuals in the same species. Use to mark territory
and signal readiness to mate.
c. Sound Signals – birdsong, cricket song, toad calls, dolphins, whales.
d. Language – most complex form of communication. Only used by
humans.