ethology and animal behavior chapter 24 behavior – way a whole animal reacts to internal or...

Ethology and Animal Behavior Chapter 24

• Behavior – way a whole animal reacts to

internal or external stimulus

•Through movements, postures, displays, eating,

eliminating, mating, caregiving, sounds, smells,

hiding, threatening, killing etc.

Behavior

• Behavior

•Varies among species

•Varies among members of same species

•Determines fitness – ability to survive and

reproduce

•Determined by natural selection (at least in part)

Behavior

• Knowledge of behavior

• Important in determining proper management

•e.g. piglets nurse more frequently if recorded

sounds of nursing piglets are played

•Human behavior follows many of the same

patterns as animal behavior

Causes of Behavioral Responses in Animals

• Determined by heredity (internal factors)

• Determined by learning experiences (external

factors)

Causes of Behavioral Responses in Animals

• Hereditary influences

•Breeds selected for certain behaviors

•e.g. horses selected for work, running, draft etc

•No one breed excels in all behaviors

Innate Behavioral Patterns

• Evidence that behavior has genetic basis

•Selection to develop breeds with unique behavior

•Animals show behavior pattern unique to their

breed even if reared artificially

•Some behaviors segregate in Mendelian fashion

(i.e. crossbreeding)

Innate Behavioral Patterns

• Thresholds

•Level of stimulus needed to display a behavior

•Some lines have very low threshold (e.g . fighting

dogs will fight at small provocation)

Innate Behavioral Patterns

• Direct hereditary influences on behavior

•Heredity affects organ size and response

•Heredity affects enzymes and hormones

•Vary widely among lines different behaviors;

animals can show only behaviors for which they

have appropriate mechanisms

Experience and Learning

• Behavior based on instincts and reflexes

• Behavior expands or contracts from instinct

due to experiences

• Habituation (e.g. adapt to environment)

•Animals develop habits quickly if experiences

direct that development in a consistent manner

Experience and Learning

• Conditioning – two types:

•Classical conditioning (associative learning)

• response to previously neutral stimulus

• Pavlov’s dogs

• provided a sound whenever fed

• would start to salivate just from the sound

• Dairy cows start to “let down” milk just from

being let into milking parlor

Experience and Learning

• Conditioning

•Operant conditioning (reward/punish)

• response to positive or negative reinforcement

• horse receives treat when performing a trick

• will do trick whenever offered the treat

• animals stay away from electric fence after shock

experiences

• https://pantherfile.uwm.edu/johnchay/PL06/OC/OC.html

Experience and Learning

• Insight learning (reasoning)

•Ability to respond correctly at a new experience

•Early malnutrition appears to interfere with

reasoning ability

Experience and Learning

• Imprinting

•Newly hatched duckling will adopt any moving

object as its parent

•Can be accomplished only very early in life

Intelligence

• Organization of behavior

• Varies widely between and within species

• Conventional wisdom is that mammals are

more intelligent than non-mammals

• Order of mammalian intelligence

•Primates – monkeys, chimps, gorillas, humans

•Ocean mammals – whales, dolphins

•Carnivores – dogs, cats

•Ungulates – pigs, horses, cattle, sheep etc

Motivation

• Internal state of animal which drives it to

behave a certain way

•Hypothalamus controls several types of behavior

• appetite

• sexual behavior

Animal Communication

• Sounds

•Animals will respond to call of distress

• from offspring

• from another member of their species

•Some species emit radar type sounds

• bats, dolphins

Animal Communication

• Chemicals

•Pheromones

• chemical substance that attracts others

• many species – pheromones used to attract mate

•Urine or feces used to “mark” territory

Animal Communication

• Visual displays

•Many birds – use wing or feather displays in

courtship

•Many mammals – raise hair on neck when fearful

•Honeybees – workers use a dance to indicate food

supply

Orientation Behavior (Homing)

• Many anecdotes

•About dogs, cats etc – find way home over long

distance

• Salmon

•Hatched in freshwater stream

•Swim to ocean

•Return to same stream to spawn

Ingestive Behavior

• Eating and drinking

•First behavior – suckling

•Teeth pattern affects ingestion

• swine and horses have full set of teeth in both jaws

• ruminants – cattle, sheep, goats

• no upper front teeth

Ingestive Behavior

• Ruminant intake

•Food is taken in, chewed, swallowed

•Later is regurgitated and chewed again

• behavior is called “rumination”

•Grazing behavior affects forage and range management

• usually eat more tender parts first

• in overgrazing situation, more palatable plants may be

eliminated

Ingestive Behavior

• Cattle spend 1/3 to ½ of time grazing

• Cattle graze at all hours of day

•Some more at daybreak, late afternoon, just before dark

•Nursing occurs both day and night

• most often at daybreak, midday and dusk

Ingestive Behavior

• Pigs born with tendency to root (dig in soil)

•Will root less if fed well-balanced diet

• If fed a grain and protein supplement separately

•Pigs will come close to balancing their own diet

Eliminative Behavior

• Some animals deposit feces randomly

• Other animals follow a pattern

• Farm animals tend to behave in this area like their

wild ancestors

Eliminative Behavior

• Cattle defecate randomly

•Will lie in feces

•Will avoid eating plants near fecal deposits

• Cattle usually urinate randomly

• Sheep follow similar pattern as cattle

Eliminative Behavior

• Swine are thought by many to be unclean

• Swine actually very clean animals

•Usually deposit feces in a corner

•Frequently deposit feces near source of water

•Proper design of swine pens will promote regular

patterns of defecation and urination

Eliminative Behavior

• Horses will return to a single place for defecation

• Poultry defecate at random, except heavy in

roosting place

• Cats bury feces

• Dogs tend to defecate in specific places

Shelter-Seeking Behavior

• Reasons to seek shelter

•Protection from:

• sun

• wind

• rain

• predators

• insects

Shelter-Seeking Behavior

• Behavior prior to storms

•Cattle will descend from high mountain pastures just

prior to a storm

• Cattle will seek shade during heat of day

• Cows will congregate around water at same time

each day

Shelter-Seeking Behavior

• Swine seek shade or wallow in water when hot

•Need for evaporative cooling

• Swine will sleep huddled together when cold

• Cattle, horses sheep will turn away from storm

• Bison face into a storm

Agonistic (Fighting) Behavior

• Involves:

•Threat

•Aggression

•Submission

•Escape

•Passivity

Agonistic (Fighting) Behavior

• Intact males will fight for mating rights

• Castrated males tend to be docile

• Boars, bulls, rams, stallions that run together from

young age seldom fight

• Dominance order already established

• In large range herds with many bulls

•Bulls will graze together at times with no cows around

Agonistic (Fighting) Behavior

• First introduction of sexually mature males

•Almost always results in a fight

•Serious injuries, seldom death, may occur

• Some breeds of cattle have been selected for

fighting behavior

Sexual Behavior

• Comprises courtship and mating

• Important because necessary to continue species

• Males are highly efficient at detecting estrus

(time of mating receptivity) in females

• Estrus in females also called “heat”

Sexual Behavior

• Estrus (heat) in females

•Sow stands still from person placing hand on rump

•Mare will squeal and urinate in presence of others

•Mares and ewes do not seek males as much as other

species

•Cows and sows will let other females mount

Sexual Behavior

• Males detect female estrus by sight and smell

• Stallion will bite and tease the female

• Boar will nudge the sow around shoulders

• Rooster will spread one wing to ground and

perform a mating dance

Mother-Young Behavior

• Maternal behavior begins at parturition (time of

birth) and continues to weaning

• Cows giving birth

•Will seek seclusion, usually in a depression or trees

•Cow will inspect calf and lick it clean

•Calf stands and starts to nurse after ~ 1 hour

•Cow eats the placenta (so as to not alert predators)

•Cow and calf rejoin herd after 2-4 days

Mother-Young Behavior

• Cow is very possessive throughout nursing period

•Will come to rescue calf very quickly

• Cows identify young primarily by smell

•Sight and sound also contribute to identification

• Time of calf removal in beef herds is very noisy

• Dairy herds – calf is separated in a few days

Mother-Young Behavior

• Sows build nest ~ 18 hours before birth

• Time of farrowing - ~ 4 hours

• A few sows become agitated and kill piglets

• Crossfostering is possible within first few days

• Frequently each piglet adopts a single teat

Mother-Young Behavior

• Sheep behave similarly to cattle in many way

around birth

• Ewes will accept orphan goats to nurse

• Mares also behave in a similar manner

• Mule foals receive as much attention as horse

foals

Investigative (Exploratory) Behavior

• Exploration through:

•Seeing

•Hearing

•Smelling

•Taste

•Touch

Investigative (Exploratory) Behavior

• Most farm animals appear curious

•Will advance on new object looking, listening and

smelling

•Sheep tend to be more timid than cattle or swine

•Will try to return to “flight zone” or area of normal

comfort if startled

Gregarious Behavior

• Species and breeds vary in terms of “flocking”

instinct

• Breeds developed in lush areas tend to be

gregarious (stay together in groups)

• Breeds developed in harsh areas tend to spread

out more

Gregarious Behavior

• Sheep - particularly strong gregarious behavior

• Sheep also follow a leader

• “Judas” goat – goat used to lead lambs to desired

location at a market place

• Swine are gregarious – modern production practices limit

the behavior

• Horses also run in “bands” – useful in training a team for

draft purposes

Social Dominance

• Well organized social rank order

•Prominent in many farm species

•Most obvious when species tends to fight or when

resources are limited

•Especially evident in chickens

• hens will fight to establish the “peck” order

• roosters assume dominance during laying season

Social Dominance

• Advantage – gives mating preference to strongest

males (important for sustaining genetic merit for

strength in a species)

• Disadvantage – weaker individuals are sometimes

deprived of food if it is limited

• Genetic contribution – appears to be moderately

heritable

Population Density and Animal Behavior

• Population density in an area is fairly constant in

many wild species

• Regulators of population size

•Predation

•Starvation

•Accidents

•Parasites

•Disease