• Behavior is what an animal does
and how it does it.
What is Behavior?
• Animal behavior asks what, why, and
• Animal behavior is also referred to as
– Scientists who study animal behavior
are called ethologists.
• Animal behavior is
the ability to move.
– Animals seek
– Animals play with
– Animals seek
• Why do animals do what they
– Why do birds sing?
– How do sea turtles navigate the
ocean to lay their eggs on the
same beach where they were
– How do honeybees know when
the hive needs more food?
Image from http://www.nps.gov
Image from http://www.scottcamazine.com
• Behavior results as a reaction
to a stimulus.
– A stimulus is a detectable
change in the animal’s internal
or external environment.
– Visual cues(stimulus).
– Hormonal changes.
Image from http://www3.nau.edu/biology/
• Ethologists do not attempt to describe WHY an
animal does a behavior before describing
WHAT the animal is doing.
– This removes as much bias as possible – good
scientists don’t want to just “see what they want to
– Need to make objective observations of animal
behaviors, analyze the data statistically, then come
to conclusions about WHY an animal behaves a
• For example, you see two cubs interacting
with each other, rolling and hopping
around, running to and from each other.
– As a behavioral ecologist, you would first state
the behavior you are observing.
– Once you made the observations about WHAT
was happening, you could begin to determine
WHY they are behaving that way.
• The behavior you
observed could have
been many different
– Mating rituals.
– Aggression, defending
How to determine WHY – action patterns.
• Action patterns are complex behaviors that are
always repeated the same way by a species of animal.
– We say that action patterns are stereotyped, since
they occur the same way each time, and through to
– After repeatedly observing action patterns, an
ethologist can analyze the data statistically.
– (Statistics is the study of the collection, organization, analysis,
interpretation and presentation of data)
– Only then do we attempt to determine WHY a
behavior is being done.
– Fixed Action Patterns (FAP) are INNATE
• Niko Tibergen(noble prize
holder) was a pioneer(first
to do something) in the field
of ethology and
– He observed animals in
their natural conditions,
something), or varied the
conditions to see how the
animals responded.Image from http://nobelprize.org/
• Tinbergen observed how a
wasp called the beewolf finds
its nest among other beewolf
– He observed that the beewolf would
circle its nest in an ever-widening
circle before flying away to hunt.
– This behavior was an action pattern
– it was performed exactly the same
way each time.
Image from http://www.sciencenews.org
• After the beewolf flew off,
Tinbergen would move certain
landmarks around the nests.
• When the beewolf returned, it
– So, by manipulating the beewolf’s
environment, Tinbergen came to
the conclusion that the beewolf
commits landmarks to memory to
be able to find its nest when it
comes back from hunting!
Image from http://www.earthlife.org
• Tinbergen had to describe and
investigate WHAT the organism
was doing before attempting to
More on Action Patterns
• The egg-rolling
behavior of the greylag
goose is a good example
of an action pattern.
• Niko Tibergen and
another pioneer in
observed this behavior.
Image from http://www.grayimages.co.uk
More on Action Patterns
• The goose will roll an egg that
is outside the nest back into the
nest in the same manner every
– Interestingly, the goose will do
this with any round object
placed outside the nest!
– Every time this action pattern is
initiated, it is carried through to
Proximate vs. Ultimate Causes
• The question of “WHY” can have different answers.
• Proximate causes are related to internal changes in
– Messages from the nervous system.
• “Proximate” means close.
• Ultimate causes are related to the survival and
reproductive success of the animal.
• “Ultimate” means furthest, or utmost.
Proximate vs. Ultimate Causes
• An example incorporating both
proximate and ultimate causes:
Belding’s ground squirrels.
– When males reach about two months
old, they leave the burrow where
they were born.
• It is an increase in testosterone, or a
hormonal change that triggers this
• So, the proximate cause of the nest-
leaving behavior involves the increase
in testosterone levels in the squirrel.
Proximate vs. Ultimate Causes
• There is more to the story than just hormones!
– When males leave the nest, they avoid inbreeding
with sisters or cousins, etc.
– Their offspring are therefore healthier.
– The male offspring inherit the same genetic
information that induces them to leave their nests at
a young age.
– So, this behavior is passed on genetically, and it
makes for a healthier population of squirrels.
– Avoiding inbreeding is therefore the ultimate
cause of this “early nest-leaving” behavior.
Interaction between organisms and the biotic and
• Abiotic- non living; e.g., temperature, light,
dissolved gas, water
• Biotic- living; e.g., predators, prey, mates
The study of the behavior of organisms within an
• e.g., communication, finding food,
protection from predators
Mechanistic basis for behavior:
A. Identify the stimuli that triggers the behavior or
B. Study the psychological, neuronal, and
hormonal changes that underlie the behavior
Distribution & Migration
Map of Pacific Golden
• External stimuli- changes in day
length and temp
• Internal stimuli - hormone levels
Winter plumage Breeding plumage
Ultimate causes - address the evolutionary
significance for a behavior and why natural
selection favors this behavior.
• Why did a behavior evolve?
• Is it adaptive?
• Does it contribute to reproductive success?
Example: birds that migrate have a selective
advantage over birds that don't/didn't, selected
for over time, could be due to long term climate
changes, glaciation, disease, taking advantage
of food sources, etc.
Nature versus Nurture:
Revisiting an Old Debate
• Not genetically
Behavior results from both genes and
A. Behavior - What an animal does and how it does it.
- some behavior is learned, some behavior is
B. To some extent ALL behavior has a Genetic Basis
1. some is totally genetic - which implies heritable
2. some is learned but relies ENTIRELY on
genetically based mechanisms
C. In general, behavior is a response to some
Innate Behaviors – inherited, instinctive
A. programmed by genes;
B. highly stereotyped (similar each time in
C. Four Categories
4. Fixed Action Pattern
1. Kinesis: "change the speed of random movement in
response to environmental stimulus“
2. Taxis: "a directed movement toward or away from a
stimulus; positive and negative taxes
3. Reflex: "movement of a body part in response to
4. Fixed Action Pattern (FAP): "stereotyped and often
complex series of movements, responses to a specific
stimulus", hardwired, however, not purely genetic, may
improve with experience
a. programmed response to a stimulus
b. stimulus of FAP = "releaser", sometimes called "sign
- courtship behavior
- rhythms - daily (circadian); annual (circannual)
D. Characteristics of Innate Behaviors -
1. The behavior is performed correctly the 1st
time without prior experience (no
opportunity to learn)
2. Triggered by some external stimulus
3. Once started, run to completion with no
4. Breeding crosses produce hybrid behaviors
• Ethology is the study of how animals
behave in their natural habitat.
–Karl von Frisch: bee communication
–Niko Tinbergen: herring gull experiment;
–Konrad Lorenz: imprint in geese
Classical ethology presaged an
evolutionary approach to
Karl Von Frisch- communication in bees
Herring gull experiment by Niko
Releaser Stimuli- stimuli that release FAP
E.g., Chick and red dot on gull parents beak
triggers feeding response- parent regurgitates
Laysan albatross feeding chick
digger wasps use
to keep track of
Move pine cones
Visual cue is
rather than objects
Egg rolling behavior in geese is a Fixed Action
Male three-spined stickleback shows
aggression at models with red undersides
• Cost-benefit analysis of foraging behavior.
–Foraging is food-obtaining behavior.
• The optimal foraging theory states that natural
selection will benefit animals that maximize
their energy intake-to-expenditure ratio.
Of Drops Required
to Break Shell
Total Flight Height
(Number of Drops ×
Height per Drop)
2 55 110
3 13 39
5 6 30
7 5 35
15 4 60
• The behavior is adaptive - signs that natural
selection is at work
a. survival may depend on behavior, learning
not an option (one chance only)
b. animals with simple NS may not have
capacity to learn
- not strictly true, "simple" animals learn
c. social interactions dependent on survival
require rigid performance of roles
mating rituals, termite mounds
Learning - Learned Behavior: Five Categories
1. a strong association learned during a specific
a. "sensitive period" or "critical period"
b. imprinting of baby geese on mother - Lorenz
baby geese imprint on mother within hours of
will imprint on any object during that period
2. learning a releaser for an innate FAP
Goose imprinting by Conrad Lorenz
Geese imprint on the first moving (with sound) object that
they see after birth
There is a selection of a specific period of time (critical
period) for social attachment and mate recognition in
geese (to ensure geese imprint on the same species)
Imprinting in conservation biology:
Need to minimize/eliminate human
presence while raising California Condors
1. decline in response to a harmless,
filter - prevents animal from wasting
energy/attention on irrelevant stimuli
C. Conditioning - laboratory setting
1. classical conditioning
animals make associations - Pavlov's dog associates bell
with food, begins to salivate, can be extinguished and later
followed by recovery (unconditioned stimulus - meat,
unconditioned response - salivation, conditioned stimulus -
bell, conditioned response - salivation)
a. animal learns to perform an "old" response to a new
b. Pavlov's dog
- place dried meat powder in dog mouth - salivation
- associate with bell - salivation to bell
c. Stimulus first, behavior second
(but of course there is an expectation of reward second)
2. operant conditioning
a. perform behavior to receive reward or avoid punishment
b. Skinner Box - levers, reward - self training elaborate
c. behavior first, reward second
(but of course there is a stimulus, if only a thought of
• Operant conditioning.
–This is called trial-and-error learning - an
animal learns to associate one of its own
behaviors with a reward or a punishment.
D. Trial and Error Learning - nature
1. natural operant conditioning
2. modify responses to specific stimuli
(releasers) - making both more
3. modify releaser to specific FAP -
making both more adaptive
Observational learning - social imitation
Octopus opening jar with crab
Trial & Error & Observational Learning
• Play as a behavior has no apparent external
goal, but may facilitate social development or
practice of certain behaviors and provide
Practice and exercise may explain the
ultimate bases of play
E. Insight, reasoning
1. manipulating concepts in the mind to arrive at
2. mental trial-and-error
3. internal memory stores are used as additional
All examples of tool-using:
• chickadees/tits and opening milk bottles
• Egyptian Vulture - uses rocks
• Cocos Finch - uses splinters of wood
• North American Gulls, Northwestern Crow - smash
clams on sandy beaches
• Cognition is the ability
of an animal’s nervous
system to perceive,
store, process, and
use information gathered
by sensory receptors.
The study of cognition connects
nervous system function with behavior
• Migration Behavior.
–Migration is the
of animals over
–Piloting: an animal
moves from one
to another until it
Whale Migration Routes
• Orientation: animals can detect directions and
travel in particular paths until reaching destination.
– Navigation may use cues including the earth’s
magnetic field, the sun, and the stars.
Adults who made
the trip before
W & SW
Social Behavior in Vertebrates
A. Predator Avoidance Behavior
B. Reproductive Behavior
C. Parental Behavior
E. Cooperative Behavior
• Courtship behavior consists of patterns that
lead to copulation and consists of a series of
displays and movements by the male or
Natural selection favors mating
behavior that maximizes the quantity
or quality of mating partners
• Certainty of paternity can influence mating
systems and parental care.
–If the male is
unsure if offspring
are his, parental
likely to be lower.
Male sea spider cares for eggs
Bastian Mimicry- palatable species resembles
an unpalatable one
Mullerian- two or more unpalatable species resembles
blenny (Aspidontus taeniatus) mimics Hawaiian cleaner
shortnose wrasse mimics Potter's angel which sports a
–Hamilton’s Rule and kin selection.
• William Hamilton proposed a quantitative
measure for predicting when natural
selection would favor altruistic acts.
• Hamilton’s rule states that natural selection
favors altruistic acts.
– Kin selection is the mechanism of inclusive
fitness, where individuals help relatives
– Reciprocal altruism, where an individual
aids other unrelated individuals without any
benefit, is rare, but sometimes seen in
primates (often in humans).
Sociobiology connects evolutionary
theory to human culture