Animal Behavior Ch 13 - Stephanie Dietterle Webpage

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Animal Behavior
Chapter 13
Sec 1: What is Behavior?
• The Behavior of Animals
– An animals behavior consists of all the actions it
performs
– Examples: behaviors include actions an animal
takes to obtain food, avoid predators, and find a
mate
– Like body structures the behaviors of animals are
adaptations that have evolved over long periods
of time
Sec 1: What is Behavior?
• The Behavior of Animals
– Most behavior is a complex process in which
different parts of an animals body work together
– Think about what happens if a water current
carries a small animal to a hydra’s tentacles. After
stinging cells on the tentacles catch the prey, the
tentacles bend toward the hydra’s mouth. At the
same time, the hydra’s mouth opens to receive
the food
Sec 1: What is Behavior?
• The Behavior of Animals
– Behavior as Response
• The touch of the prey on the tentacles acts as a
stimulus to the hydra
• A stimulus is a signal that causes an organism to react
in some way
• The organisms reaction to the stimulus is called a
response
• The hydra’s response to the prey is to sting it
• All animal behaviors are caused by stimuli
Sec 1: What is Behavior?
• The Behavior of Animals
– The Functions of Behavior
• Most behaviors help an animal survive or reproduce
• When an animal looks for food or hides to avoid a
predator, it is doing something that helps it stay alive
• When animals search for mates and build nests for
their young, they are behaving in ways that help them
reproduce
Sec 1: What is Behavior?
• Behavior by Instinct
– Animals perform some behaviors by instinct,
without being taught
– An instinct is a response to a stimulus that is
inborn and that an animal performs correctly the
first time
– Example: a newborn kangaroo instinctively crawls
into its mother’s pouch and attaches itself to a
nipple. Without this instinct, baby kangaroos
could not obtain the milk they need to survive
Sec 1: What is Behavior?
• Learned Behavior
– Learning is the process that leads to changes in
behavior based on practice or experience
– Learned behavior include imprinting, conditioning,
trial-and-error learning, and insight learning
– Cause learned behaviors result from an animals
experience, they are not usually done perfectly
the first time
Sec 1: What is Behavior?
• Learned Behavior
– Imprinting: certain newly hatched birds and
newborn mammals recognize and follow the first
moving object they see (usually the mother)
– Imprinting involves a combination of instinct and
learning
– The young animal has an instinct to follow a
moving object, but is not born knowing what is
parent looks like
Sec 1: What is Behavior?
• Imprinting
– Once imprinting takes place, it cannot be changed
– Imprinting is valuable for two reasons. First, it keeps
young animals close to their mothers, who know
where to find food and how to avoid predators
– Second, imprinting allows young animals to learn
what other animals of their own species look like
– The ability protects the animals while they are young.
In later life, this ability is important when the animals
search for mates
Sec 1: What is Behavior?
• Learned Behavior
– Conditioning: learning that a particular stimulus or
response leads to a good or a bad outcome
– Here is how the conditioning works: at first, a puppy
rarely comes when you call. Each time the puppy
comes when you call, you give it a dog biscuit. Your
puppy will soon learn to associate the desired
response – coming when called – with the good
outcome of a food reward. To get the reward, the
puppy learns to come every time you call. After a
while, the puppy will come to you even if you don’t
give it a dog biscuit
Sec 1: What is Behavior?
• Learned Behavior
– Trail-and-Error Learning: an animal learns to
perform a behavior more and more skillfully
– Through repeated practice, an animal learns to
repeat behaviors that result in rewards and avoid
behaviors that result in punishment
– Many animals learn by trial-and-error which
methods are best for obtaining food
– They also learn which methods to avoid
• Example: snunk
Sec 1: What is Behavior?
• Learned Behavior
– Insight Learning: when you solve a problem or
learn how to do something new by applying what
you already know, without a period of trial-anderror
– Insight learning is most common in primates, such
as gorillas, chimpanzees, and humans
– Example: chimps use twigs to probe into the nests
of termites and other insects that they eat
Sec 2: Patterns of Behavior
• Communication
– Animals use mostly sounds, scents, and body
movements to communicate with one another
– An animals ability to communicate helps it
interact with other animals
– Animals communicate many kinds of messages
using sound
– Some animals use sound to attract mates
• Example: female crickets, are attracted to the sound of
a male’s chirping
Sec 2: Patterns of Behavior
• Communication
– Animals may also communicate warnings with sound
• Example: when a coyote or other predator approaching, a
prairie dog makes a yipping sound that warns other prairie
dogs to take cover in their burrows
– Animals also communicate with chemical scents
– A chemical release by one animal that affects the
behavior of another animal of the same species is
called a pheromone
• Example: perhaps you have seen a male house cat spraying a
tree, this scent advises other cats in the neighborhood of his
presence
Sec 2: Patterns of Behavior
• Competitive Behavior
– Animals compete with one another for limited
resources, such as food, water, space, shelter, and
mates
– Competition can occur among different species of
animals
• Example: a pride of lions may try to steal a prey from a
troop of hyenas that has just killed the prey
– Competition can also occur between members of
the same species
Sec 2: Patterns of Behavior
• Competitive Behavior
– Showing Aggression
• Aggression is a threatening behavior that one animal
uses to gain control over another
– Example: before a pride of lions settles down to eat its prey,
individual lions show aggression by snapping, clawing, and
snarling
• Aggression between members of the same species
hardly ever results in the injury or death of any of the
competitors
Sec 2: Patterns of Behavior
• Competitive Behavior
– Establishing a Territory
• A territory is an area that is occupied and defended by
an animal or group of animals
• If another animal of the same species enters the
territory, the owner will attack the newcomer and try to
drive it away
• Birds use songs and aggressive behaviors to maintain
their territories
• Other animals may use calls, scratches, droppings, or
pheromones
Sec 2: Patterns of Behavior
• Competitive Behavior
– Attracting a Mate
• A male and female salamander swim gracefully in the water,
moving around one another
• Courtship behavior is a behavior in which males and females
of the same species prepare for mating
• Courtship behavior ensures that the males and females of
the same species recognize one another, so that mating and
reproduction can take place
• Courtship behavior is typically also competitive
– Example: in some species, several males may perform courtship
behaviors for a single female. She then chooses one of them to
mate with
Sec 2: Patterns of Behavior
• Group Behavior
– Living in groups enables animals to cooperate
– Although many animals live alone and only rarely
meet one of their own kind, other animals live in
groups
– Some fishes form schools, and some insects live in
large groups
– Hoofed mammals, such as bison and wild horses,
often form herds
Sec 2: Patterns of Behavior
• Group Behavior
– Safety in Groups
• Living in groups often protects animals against
predators (fishes that swim in schools are often safer
then fishes that swim alone)
• Animals in a group sometimes cooperate in fighting off
a predator
– Example: Fig 13 p448
Sec 2: Patterns of Behavior
• Group Behavior
– Animal Societies
• Some animals, including ants, termites, honeybees,
naked mole rats, and pistol shrimp, living in groups
called societies
• A society is a group of closely related animals of same
species that work together in a highly organized way
• In a society, there is a division of labor – different
individuals perform different tasks
Sec 2: Patterns of Behavior
• Behavior Cycles
– Some animal behavior, called cyclic behaviors,
occur in regular, predictable patterns
– Cyclic behaviors usually change over the course of
the day or a season
Sec 2: Patterns of Behavior
• Behavior Cycles
– Daily Cycles
• Behavior cycles that occur over a period of approximately
one day are called circadian rhythms
• For example, blowflies search for food during the day and
rest at night
• In contrast, field mice are active during the night and rest by
day
• Animals that are active during the day can take advantage of
sunlight, which makes food easy to see
• On the other hand, animals that are active at night do not
encounter predators that are active during the day
Sec 2: Patterns of Behavior
• Behavior Cycles
– Hibernation
• Other behavior cycles are related to seasons
• Example: some animals, such as woodchucks and
chipmunks, are active during warm seasons but hibernate
during the cold winter
• Hibernation is a state of greatly reduced body activity that
occurs during the winter when food is scarce
• During hibernation, all of an animals body processes, such as
breathing and heartbeat, slow down
• This slowdown reduces the animals need for food
• In fact hibernation animals do not eat; their bodies use
stored fat to meet their reduced nutrition needs
Sec 2: Patterns of Behavior
• Behavior Cycles
– Migration: is the regular, seasonal journey of an
animal from one place to another and back again
– Some animals migrate short distances
• Example: Dall’s sheep spend summers near the tops of
mountains and move lower down for the winters
– Other animals migrate 100’s of miles such as birds
– Animals usually migrate to an area that provides a lot
of food or a good environment for reproduction
– Most migrations are related to the changing seasons
and take place twice a year, in the spring and in the
fall
Sec 3: Tracking Migrations
• Technologies for Tracking
– Electronic tags give off repeating signals that are
picked up by radio devices or satellites. Scientists can
track the locations and movements of the tagged
animals without recapturing them
– In the fall of 1803, American naturalist John James
Audubon wondered whether migrating birds returned
to the same place each year
– So he tied a string around the leg of a bird before it
flew south
– The following spring, Audubon saw the bird with the
string. He learned that the bird had indeed come back
Sec 3: Tracking Migrations
• Technologies for Tracking
– Radio Tracking
• Tracking an animal by radio involves two devices
• A transmitter attached to the animal sends out a signal
in the form of radio waves, just as a radio station dose
• A scientist might place the transmitter around an
animals ankle, neck, wing, or fin
• A receiver picks up the signal, just like a radio at your
house
• The receiver is usually in a truck or an airplane
Sec 3: Tracking Migrations
• Technologies for Tracking
– Satellite Tracking
• Receivers can be placed in satellites as well as in airplanes
and trucks
• A satellite is an instrument in orbit thousands of kilometers
above Earth
• Networks, or groups, of satellites are used to track animals
• Each satellite in a network picks up electronic signals from a
transmitter on an animal
• Together, the signals from all the satellites determine the
precise location of the animal
Sec 3: Tracking Migrations
• Why Tracking is Important
– Electronic tracking tags are giving scientists a
complete, accurate picture of migration patterns
• Example: when scientists used radio transmitters to track
one herd of caribou, they learned two important things
– First, they learned that the herd moves over a larger
area than previously thought
– Second, they learned that each year the herd returns
to about the same place to give birth to its young
Sec 3: Tracking Migrations
• Why Tracking is Important
– Tracking migrations is an important tool to better
understand and protect species
• Example: Florida manatees are an endangered species, and
therefore they need protection so tracking them can help
with their protection
– Technologies for tracking animals may also help
people whose work or recreation affects animals
• Example: suppose officials at a state park want to protect a
group of migrating animals during the spring; the officials
plan to ban fishing or boating for the entire spring season
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