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
