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