Primate Adaptations and Behavior Flashcards
Primate Characteristics
▪ extant vs extinct ▪ hair ▪ sweat glands, mammary glands ▪ viviparous (live young) ▪ long ontogeny ▪ heterodont ▪ endothermic ▪ larger brain ▪ capacity for learning and behavioral flexibility
Limbs and Locomotion
▪ tendency towards erect posture (vertical spine position)
▪ flexible, generalized limb structure (move in trees and ground)
▪ engage in a number of locomotor behaviors
▪ prehensile (grasping) hands and feet, sometimes tails
▪ differ from most mammals
▪ pentadactyly
▪ opposable thumb/big toe
▪ nails
▪ highly innervated tactile pads (nerve) at the end of digits – enhanced sense of touch
prehensile
grasping hands and feet, sometimes tails
pentadactyly
5 digits on hands and feet
opposable thumb/big toe
can touch thumb with other digits
quadrupedal
moving on four limbs
bipedal
moving on two limbs
arboreal
active in the trees
ex. feeding, sleeping, socializing
terrestrial
active on the ground; more common in larger species
Vertical clingers and leapers
elongated hindlimbs (asks like springs)
ex. some lemurs, tarsiers
brachiation
▪ suspension
▪ elongated arms and hands, curved phalanges, cupped hands, extensive arm musculature
ex. gibbons and siamangs
prehensile tail
grasping tail that acts like a limb
ex. some New World monkeys from central and south America (howler monkeys)
knucklewalking
resting on middle set of phalanges
ex. African apes, gorillas
Dentition and Diet
▪ unspecialized teeth/generalized dentition – omnivorous diet
▪ fruit, leaves, gums, seeds, insects, honey, meat
Dental formula
▪ # and type of each kind of tooth in each quadrant of the jaw
▪ distinguishes primate groups
▪ #incisors: # canines: # premolars: # molars
Dental morphology
▪ size, shape
▪ cusps: bumps on chewing surface of tooth
ex. cats have sharp teeth to eat meat
Senses and the Brain
▪ large, complex brains
bony protection of the eye
post orbital bar → post orbital closure
diurnal primates
have color vision and are active during the day
nocturnal primates
have black and white vision and are active at night
stereoscopic vision
3D depth perception
binocular vision
forward facing eyes with overlapping visual fields
olfaction
decreased reliance on the sense of smell
maturation
▪ more efficient fetal nourishment
▪ longer gestation (pregnancy)
▪ reduced number of offspring, ↑ degree of care (k-selected vs r-selected)
▪ delayed maturation/longer ontogeny and learning period
▪ longer life span
life history
developmental and reproductive events that occur throughout an individual/species’ lifetime
ex. lifespan, gestation length, number of offspring, etc.
learning
greater dependence on flexible, learned behavior; social groups and permanent association of adult males
behaviour
diurnal activity pattern in most species
geographic distribution and habitats
▪ Tropical/semi-tropical areas of New World (South/Central America, Mexico), Old World (Africa, India, Southeast Asia, Japan)
▪ primates used to be everywhere bc of higher latitudes in the past then now
▪ most are arboreal in forest/woodland habitats
Strepsirhines
share common primitive behaviour and bio characteristics with earliest mammals and primates in the fossil record
ex. lemurs (Madagascar)
lorises (India, Sri Lanka, SE Asia, Africa)
Characteristics of Strepsirhines
▪ usually nocturnal ▪ tapetum lucidum (eye shine) ▪ more olfactory ▪ rhinarium (chemosensory): damp wet nose ▪ usually insectivorous ▪ usually arboreal ▪ quadrupedal ▪ vertical clinging and leaping ▪ often solitary ▪ differences in reproductive apparatus, shorter gestation and maturation ▪ tooth combs ▪ grooming claws
lorises/galagos
▪ nocturnal
▪ different modes of locomotion
▪ insects, fruits, gums, leaves
infant parking
cover infants with toxic saliva to protect them from predators
Tarsiers
▪ Southeast Asia (Malaysia, Borneo, Sumatra, Philippines)
▪ small!
▪ enormous eyes: nocturnal, can rotate head 180°
▪ no rhinarium, no toothcomb, no tapetum lucidum
▪ very long hindlimbs and feet: excellent leapers
▪ only living carnivorous/insectivorous today
▪ small group size
Platyrrhines: New World Monkeys
▪ Central and South America, Mexico ▪ ~70 species ▪ 12 oz –20 lbs ▪ arboreal ▪ quadrupedal ▪ some with prehensile tails, some semibrachiators ▪ diurnal (except owl monkey) ▪ omnivorous ▪ most live in social groups including both sexes and all age categories
Sexual dichromatism
colour difference between males and females of a single species
Cercopithecoids: Old World Monkeys
▪ Africa, Asia ▪ Wide range of habitats ▪ Most are arboreal ▪ Ischial callosities ▪ Larger body size ▪ Diurnal ▪ Sexual dimorphism/dichromatism ▪ Variably sized social groups; ▪ Increased complexity
Ischial callosities
like a pillow that allows them to sit for long periods of time
▪ when female’s are red it indicates they are ready to mate
Hylobatids: Gibbons and Siamangs
▪ Southeast Asia
▪ highly suspensory - brachiation
▪ omnivorous diet
▪ monogamous pair + offspring
Pongines: Orangutans (Pongo)
▪ Borneo and Sumatra ▪ suspensory, quadrumanous climbers, fist walking ▪ frugivorous ▪ extremely sexually dimorphic ▪ solitary
Gorillas (Gorilla)
▪ Equatorial Africa ▪ largest of the living primates ▪ primarily terrestrial, knucklewalking ▪ More folivorous/frugivorous ▪ Groups consist of one large silverback male, a few adult females, and their offspring
Chimpanzees (Pan troglodytes)
- Equatorial and Western Africa
- smaller than gorillas, less sexually dimorphic
- arboreal; terrestrial: knuckle walk, bipedal
- broad diet: geographic and seasonal variability; hunting!
- variable group size; complex social behavior
- More complex tool use: termite and ant sticks, hammerstones
Bonobos (Pan paniscus)
▪ Democratic Republic of Congo ▪ chimp-like ... sort of ▪ arboreal ▪ sex ▪ social groups –male/female bonded pairs ▪ diet similar to chimps
