ch 14 and 15 Flashcards
tarisers
(prosimian) have the largest eyes in proportion to body size of any known animal
primates
order of mammals including humans nad nearest relatives. Have great range of sizes, lifestyles and adaptive behaviors.
Interesting to scientists b/c: 1. similarities of primates and humans 2. unique features that set humans apart
when did primate evolution began
when dinosaurs died and small shrewlike ancestors of all mammals became arboreal
primate adaptations to tree-living
- five digit hands with a thumb(opposable thumb and forefinger increases gripping power, precision, dexterity needed for living in trees. Humans have most sensitive and agile hands in nature)
- Nonspecialization (primates kept 5 digits of ancestors but did not specialize them for other functions, like swimming or running. Frees hands for a variety of purposes)
- Limb flexibility (primates evolved ability to rotate arms in sockets and rotate hand 180 degrees without moving arm or elbow. Only in humans, apes, monkeys, and some prosimians)
primate characteristics
- Nails rather than claws (nails leave han and digits free to feel and explore, claws better suited for running, predations, defense.
- visual acuity (aboreal species need good vision to survive. Gradually primates evolved frontal eyes and 3-d vision. High acuity enhanced by color vision
- upright posture (primates eventually stood up for visual scan. Led to bipedalism. freed hands to deal with what the eyes could see.)
primate classifications
185 species of living primates
prosimians evolved first
monkeys
apes (Gibbons, Orangutans, Humans)
apes
evolved from old world monkeys
Gibbons- split off 12 million years ago
Orangutans- 10 million years ago
Humans- diverged from gorillas and chimps 6 million years ago
Apes differ from monkeys in that they: have no tail, have arms longer than their legs which allows them to brachiate (swing from branch to branch)
prosimians
Ancestors- first group emerged 38-65 million years ago. EArly species spread further norht and south because climate was warmer
Modern Prosimians- approx 35 species of lemurs, pottos, bush babies, lorises, tarsiers
smaller, furry, arboreal, nocturnal. diet consists of insects or plants. Less humanlike with longer noses and smaller brains
most exist in africa and tropical southern asia
Creepers: Lorises
dutch word 'lores' means sluggish. solitary nocturnal 1. slender loris 2. slow loris move slowly and deliberately along tree branches large eyes-to see at night slow movements- less likely to fall most vertebrae of any primate- for bending strong gripping hand- good for traveling in trees move slow, slow metabolic rate naked moist snout, keen smell sleep in day
creeps: Lorises offspring
female bears one offspring per year
born pink and hairless
mother carries young on stomach fur
later, leaves young on tree branch early in night to feed
after a few weeks young follows mother or clings to her back
young learns what foods to eat on their travels
Creepers: Lorises when under attack
gland on inside of elbow releases toxin when under attack. smell compared to sweaty sock, causes pain
when threatened lift arms up over head, exposing gland
may also lick the gland and rub it on their teeth giving them a venomous bite
mother can rub on her babies ot make them unpalatable
Leapers: Lemurs
Diurnal prosimians
evolved on madagascar
adapted to all habitats of the island leading to a variety of differing species
Mouse Lemur-solitary, territorial, aggressive
Indri-lives in small, peaceful family groups
Leapers: Lemurs most common
ring-tailed lemur (lemur catta)
fox like nose, yellow eyes
long furry tail
makes sound like cats meow but can also scream, grunt, and bark
eats leaves and fruit
can leap from tree to tree
agile on ground but don’t stay there long
extensive scent marking sets large territory
can live for 25 years
ring tailed lemur
most common lemur
live in troops up to 25
stable structure of female dominance hierarchies
adults females enter estrus in march, area around genitals swells, release reprodutive pheromones. adult males respond to pheromones with increased sperm production and become more active and violent toward one another.
in early april individual females may go off with single dominant male “consort”
hanging out, grooming one another, cuddling.
eventually a mating frenzy takes over the troop. normally low ranking males challenge superiors, former male coalitions dissolve, males from other troops challenge alpha males, male consorts have trouble keeping their mates
one pup or twins born after 4 months. birth in dry season, mature before rainy season to survive
ring tailed lemur pups
altricial except for strong grip
extensive observational learning
what to eat, how to forage, what their place is in society
alpha and beta females- mothers relax on ground and are attended to by the troop. young female attendants, aunts, babysit for the mothers
infants of low ranking females must learn submission
New World monkeys
monkeys evolved next from prosimian ancestors 28-53 million years ago
platyyhines: flat nosed (sideways facing nostrils)
larger and more prominent skulls
greater intelligence
full color, 3d vision
less dominated by smells
no buttock pads
Callers: Howler Monkeys
six species of largest and most widespread monkeys of central and south america
arboreal and diurnal
sleep or rest for half the day
slow moving when awake
tails used to grasp branches
eat low sugar low nutrition leaves
specialized colon with bacteria for digesting leaves
prefer sugary fruits, young leaves, unusually nutritious leaves-although lifestyle doesn’t require much energy
sexually dimorphic males larger
Callers: howler monkeys social situation
live in groups that vary with population density, according to abundance of food
when low, small groups, when high, larger groups
in all groups females provide parental care and male provide leadership and settle disputes
Callers: Howler Monkeys Howler calls
among loudest animals sounds
can be heard up to km away
amplified by prominent larynx bulging beneath chins
group occupying a territory howls loudly at dawn
different groups can avoid each other as they forage, avoiding conflict and territorial dispute
if groups do meet, smaller less dominant groups usually give way rather than fight.
Squabblers: Squirrel Monkeys
more highly populated primate species
physical characteristics: white faces, dark eyes and mouth, long tails help keep balance
behavioral char: diurnal with constant activity, bold, curious, quarrelsome squabblers. not territorial, different species may live together in same tree with little overt aggression
live in large multi male troops
eat fruits and flowers and insects
females give birth to single offspring each year, mother provides parental care, sometimes get help from female friends
old world monkeys
largest group of living primates
evolved in africa and spread to southern asia
catarrhines: downward pointing nostrils
medium to large
range from arboreal (colobus monkey) to fully terrestrial (baboon)
prominent buttock pads they can sit on
unlike apes in that most have tails although unlike new world monkeys, not prehensile
Lookers: Guenons
ex. blue monkey
small, omnivorous
female harems, dramatic sexual dimorphism
troops have more than 1 breeding male when troop is larger or more dispersed, or when troop has several females in estrus at same time. one male is dominant. dominant male cannot prevent access of intruder male to females, intruder must stay with troop for some time since females will not mate with strangers. dominant male may keep status for 2 years, eventually displaced by more dominant male. New males may try to kill infants, although females sometimes gang up to prevent
Lookers: Guenons: Blue Monkey Aggression
relatively rare
usually involves dominant male harassing and driving off sb adult males
occurs primarily when territories overlap and overlap contains valued fruit trees
all troop members defend boundaries against neighboring troops but live near other monkey species
Lookers: Guenons: Blue Monkey communication
communication needed for group cohesion
vocal communication useful in dense jungle
low pitched boom sound of dominant male
cohesion calls to keep intruders away or warn of danger
females have own distinct sound
visual communication through facial expressions, postures, and tail positions
Lookers: Guenons: Blue monkey reproduction
seasonal reproduction
no obvious sign of female’s repdocutive state
receptive female takes initiative by approaching male, grunting and with tail raised
presents hindquarters to male who mounts
after 140 day gestation newborn
stays exclusively with mother for firth month
at two months coat appears gray and young may travel away from mother briefly
later mother leaves infant in care of other females
must learn tree travel routes and territory
Lookers: Guenons: Evolution
Guenon evolution as an interesting problem
most species are highly similar in basic body structure, habitats and diets and vocal calls
why so many different guenon species
some evidence that habitats in africa once isolated long enough for different mutations to occur producing different species. Different species become united later as africa became one large, interconnected jungle continent.
differences in appearance with vivid and distinctive facial colors and body markings.
interbreed in captivity but rarely in the wild, breed with animal with similar facial pattern
Walkers: Savanna Baboons
adapted for living and walking on all fours
four subspecies 1. guinea, 2. olive 3. yellow 4. chacma
adults of 2 ft long and weight up to 100 lbs
arms and legs similar length with heavily muscled shoulders
tail held in crooked arch over their back
live 25 years
climb rocks trees or high ground at night to sleep
sit on tree branches, can feel branch sway if predator approaches
Walker: Savanna Baboon Habitat and diet
open areas grasslands scrubby forests travel constantly and forage for food walk, dig, climb trees, chase prey diet of eclectic omnivore-adapt to whatever available cheek pouch used to store food
Walkers: Savanna Baboons social behavior
live in socially complex troops 30-50 individuals all related in some way
pronounced male dominance hierarchy
males compete for access to estrous females
sexual dimorphism.
one alpha male- largest
changes in facial expression and subtle vocal signals may indicate change in emotional state
females also have dominance hierarchy. rank determined by mother in reverse age order. permanent by 2.5 years of age
social grooming aids bonds
Walkers: Savanna Baboons Defense
male dominance hierarchy capable of protecting troop from predators like lions, cheetahs, hyenas, and leopards
baboons are among few primates adapted to stand and fight predators, not just to run away
dominant male directs troop movements
different troops usually avoid each other
intertroop aggression may occur in competition for same resources
Walkers: Savanna baboons Reproduction
female menstrual cycle similar to humans
communicate readiness through swelling and redness of genitals and scent pheromones
female presents hindquarters to favorite male
exhibits characteristic posture indicating readiness
play some role in selecting partners (not just one)
male is always ready
may show courtship behaviors such as play chasing and grooming
dominant male always has access to estrus females, although others can mate before or after
Walkers: savanna baboons offspring
six month gestation
parental care needed for about a year
couples often stay together to raise infant
males will become foster parent if mother is killed
infants start riding jockey style by 6 weeks during foraging, can climb trees by 4 months sexual maturity by 5-8 years
females may harass mother to be close to an infant
male godfathers (associates of new mother) may hold, groom, carry, and share food with young. often lasts well into second year. may experience more reproductive success
female offspring remain with mother for life, male offspring remain with mother until age 4
apes vs. monkeys
apes lack a tail
apes have arms longer than their legs
apes have mobile, rotary shoulder joint which allows them to brachiate and hang from arms
apes have more upright posture and can walk on two legs
classification of apes
16 species of apes split into two families
Hylobatidae- lesser ape (gibbons)
hominidae- great apes (orangutans, gorillas, chimps, humans)
Swingers: Gibbons
lesser apes
arboreal with different species separated
eat fruits, young leaves, birds eggs,
endangered
small, quick, agile
each species has distinctive coat colors, facial patterns, and vocal patterns
diurnal, go to sleep before dark, sleep on branches in sitting position
use brachiation
can stand, walk upright, and run from tree to tree. most bipedal of all non-human primates
many say that Gibbons are the most successful of modern living apes: (live high in trees, small enough to be quick and agile, unlimited food supply, total freedom from predators, little sexual dimorphism)
swingers: Gibbons reproductive behavior
unusual primates in forming monogamous pairs, and living with their offspring
gestation period 7-8 months
couple delivers one offspring every 2-3 years
family often contains 2-4 youngsters at a time
Swingers: Gibbons maternal behavior
offspring clings to mother’s waist as she swings through trees to forage
weaned early in second year to participate in social life by grooming and playing with infants
siamang male unusual in participating in infant care and sometimes taking over care after first year
mature at 6 years
same sex parent drives away youngster by eighth year
orangutans
first of great ape species to evolve 10 million years ago
orangutan means “person of the forest”
widely dispersed in difficult habitat
highly intelligent
solitary and shy by nature (except mother and infant)
thus difficult to study
heaviest tree-dwelling animals
long arms and short bowed legs can grasp with both hands and feet
orangutans physical characteristics
large head prominent mouth
males develop large throat pouches and cheek flanges
covered with long reddish brown hair
senses similiar to ours including hearing sight smell taste and touch
sleep in nests of leafy branches
great sexual dimorphism
can live longer than 60 years but average 40-50
orangutans diet
mostly fruit, also leaves shoots young plant buds, birds eggs and insects
constant foraging feed thorugh middle of day
orangutans territory
inhabit territorial range that includes as msany smaller female territories as possible
aggressive to other males that enter territory
violent displays that usually lead to retreat
males emit series of calls consisting largely of sighs and grunts lasting as long as 3 min
keeps other males away and attracts receptive females
older males can puff up throat pouches with air making head appear large which helps them amplify territorial call
orangutans mating
males and females only socialize for mating
females sexually mature at 10 years
will mate throughout menstrual cycle but mate more during times of maximum fertility
no genital swellings at ovulation
tends to associate exclusively with one male for life despite remaining solitary
associated with him for several weeks when receptive, travels with him and mates only with him
orangutans maternal care
newborn cared for exclusively by mother
baby vulnerable and helpless, clinging to mother’s fur for as long as first 2 years of life
mother may nurse for as along as 6 years and keep young near her for as long as 8
juveniles gradually become more self sufficient- establish own territory between 7 and 10, more social than adults sometimes play together
gorillas
Three subspecies 1. mountain 2. eastern lowland 3. western lowland.
classic studies of George Schaller and Dian Fossey
shy gentle intelligent sociable
gorillas appearance
black hair
long muscular arms, short legs
cannot grasp objects or tree limbs with feet
use arms to reach and pull down food without climbing
broad hands with short fingers and thumbs
wide chests and massive heads with large sharp canines
can stand erect but usually walk on all fours
use knuckles for support
no hard rump pads for sitting in trees
gorilla habitat
africa and nearby countries
lowland or mountainous tropical rain forests where vegetation is thick and plentiful
gorilla diet
up to 70 lbs of vegetation/day
primarily ground plants (bamboo shoots, leaves, stems, fruits)
must forage about half of each day to sustain large bodies
rarely drink
gorilla social behavior
live in small family groups of 8-24 individuals
twice as many females
one large silver backed male who is dominant and decides where troop rests and sleeps
usually several younger males without silver backs
during the day adult males rarely climb trees but female and young do. travel to forage, move single file with silverback in lead, nap during hottest part of day in temporary nests
at night adults sleep alone, young with mom
build more elaborate nests
gorilla display of power
get submissive reaction by tightening lips and staring
indicate displeasure and get immediate attention by growling, emitting series of panting sounds, baring teeth, strutting stiffly on all fours
roar ferociously, pound chest, and charge opponent
1. bluff charge- run at an angle past opponent
2. rush charge- run directly toward opponent but stop short
3. slam charge- run directly into opponent with powerful shoulders
single blow from the fist of a male gorilla can shatter human bones (but strength not normally used for aggression, normally used for pulling down vegetation)
large males can beat cupped palms against chest making loud pock pock
may indicate threat, sexual arousal, play frustration
All out fights between males are extremely rare since dominance displays are usually sufficient to settle the issue.
gorilla submission
to display submission cower on ground with backs exposed and belly covered. Avoid dominant gorilla’s gaze. Lip tuck (like human lip biting)
younger gorillas groom silverback to earn his good graces and secure him as an ally.
Female adults generally do not groom silverback because they already have his protection
gorilla Mating
adult females usually mate only with highest ranking male in troop that is not a relative
female in estrus about 3 days a month
solicits attention from male when receptive. presents her rump or stares with stiffened limbs male is attracted to genital odors during estrus, male may beat his chest or strut around.
copulate front to rear or face to face. in middle of troop during day. provides observational learning to troop
Gorilla Maternal behavior
females give birth only once in every 3-5 years
each offspring requires several years of care. Mothers can nurse for 2-4 years. can’t get pregnant again until lactation stops. learns social structure and experiences of troop. Gorilla mothers are among the most caring and devoted in all of nature. Groom infnats and handle extensively from birth. Infant clings to underside fur for a few weeks, then rides on mothers back. Mother scratches, rubs, nibbles at and licks infant
Gorillas socialization
young must learn social structure and experiences of troop.
solitary play- spinning on vines, doing somersaults, climbing, jumping, running, sliding down slopes, wading in water, playing with objects
group play- lunging at each other, chasing, tackling, wrestling, mock biting
dominant male will put up with lots of attention from infants, as they tug at and cling to his fur
infant often climbs trees and vines and sometimes sleeps on branches, but adults stay on ground
Gorillas reaching adulthood
young male gorillas begin to acquire silver backs around age 11-13. May leave group and remain solitary for awhile, may stay with natal family and team up with dominant male to keep intruders out, may occassionally get to mate with younger females, may eventually take over troop from dominant male.
young female gorillas usually move out of the troop to join lone males or other established groups. prevents inbreeding
silverbacks as stabilizing force
females not related to each other so don’t form core of troop. instead females bond with large dominant male silverback. silverback keeps peace between unrelated females improves foraging opportunities protects females infants, even babysits, keeps competitors out, defends against predators (although few) silverback considered great stabilizing force.
Chimipanzee
primate species most similar to humans
share 99% of genes
our closest relative, but we are not descended from them, instead we share common ancestors 3-4 may
they have been deemed second brightest species now living on earth.
two chimp species
1. common chimp
2. bonobo
common chimpanzee
jane goodall
males have longer canine teeth and may use them in fights or defense
walk on front knuckles, fingers folded inward, spending most of time on ground
black coats, with graying starting at age 20
live up to 45 years in wild
common chimp diet
fruit (banans) leaves, adapt to whatever
spend at least 4 hours a day eating, do not store food eat whatever they find.
sleep in nests of leaves which are remade every night.
adults sleep alone, mothers with child
common chimp mating and maternal behavior
females in estrus for 2 weeks every 5-6 weeks
females present hindquarters to male
preferences vary during estrus (promiscuous early in estrus, mate exclusively with dominant male late in estrus)
gestation lasts 8 months
young remain with mother until 7-7
sexually mature at 8 or 9
first pregnancy at 10 or 11
common chimp social behavior
2 groupings
1. parties- 3-6 individuals usually related. tend to stay together most of the time. typically part of a larger community
2. community (or colony) - 15-20 individuals. territory may encompass up to 150 square miles.
males remain in natal community, while females migrate to a new community
behavior in communities and parties depends on food availability (when scarce travel alone, when abundant, in community)
common chimp female migration
successful migration includes establishing own core area in range of new community. earning acceptance from existing females.
female should assess probability of success in joining new community. assess probability of new community’s success, since life may depend on int. not all are successful but more likely if female enlists protection of some resident male. teams up with member female (older females willing)
common chimp hunting
group hunting takes place at least once a week, more in rainy season
prefer colobus monkeys b/c they are larger, slower and abundant. Group hunting required since monkeys can j ump quickly from tree to tree.
hunting parties assemble and leave in silence. chimps surround monkey
1. Driver- climbs tree to surprise it and keep it moving
2. blocker- goes in surrounding tree to cut off escape
3. chaser- springs up trees to catch and kill
4. ambusher- older male anticipates where fleeing monkey will go and waits for it.
common chimp dominance hierarchy
males form loose dominance hierarchy
average male chimp much stronger than average male human
do not usually fight with male siblings
fight with other males until dominance is established
indicate dominance through: facial expressions and body gestures, hooting sounds from a distance, drum by hitting base of trees with feet and hands, charging display with hair erect, sometimes drag and bang branch of club.
indicate submission through: bobbing and crouching in front of dominant male, panting-grunting sound and baring teeth in fear-grin
dominant males tolerate and form relationships with subordinates- dominance relationships not always constant, more likely to survive in a group
male chimp society
like human society
less organized and more free flowing
less constant and predictable and more complex
relationships are less permanently defined, can change over time
as in humans, chimps capable of murder, systematically eliminating males and possibly expanding own territory like war
Bonobo
classified as separate species in 1929
initially called pygmy chimps
males slightly smaller than chimps, females same
slimmer build, narrower shoulders, longer legs, smaller head
have black face, sideways hair, can walk upright more easily, do not fear water like chimps do, some webbing between toes
dominated by females
have high emotional awareness. empathy, can take another’s perspective
bonobo sexual behavior
females receptive 75%
sexual contact with both males and females
vaginal opening more frontal fostering more front to front sex
habitually use sex to avoid or deflect conflict
males greet each other with penis rubbing
bonobos use sex to keep society bonded. no rape or coercion
Can Great apes use language
Hayes- raised chimp in his own home taight it to say a few words like cup and mama too difficult for chimps who lack coval apparatus to produce the necessary sounds
Gardners attempted to teach young, female chimp named Washoe ASL. learned over 100 words
Premack traught chimp named Sarah to use colored pieces of plastic with symbols on them
Rumbaugh, Gill, Glaserfield taught their chimp Lana to press buttons with symbols on them
however conversations are entirely pragmatic. dramatic contrast between chimps and human infants
language in orangutan
Chantek
understands spoken english and ASL
has acquired a vocab of several hundred signs
makes and uses tools, creates paintings, necklaces, crafts and music
demonstrates self-awareness by grooming himself in mirror and by using signs in mental planning and deception
language in gorilla
koko
understands more than 1,000 signs, 2,000 spoken english words
had a cat named all ball
language in bonobo
kanzi
spontaneously began using lexigrams, first bonobo to use language at all and first of any ape to learn it naturalistically. Can point ot correct lexigram when hears a spoken word. able to learn symbols faster than other apes without repetitive drills
