primates Flashcards
primate traits
Opposable thumbs Stereoscopic vision Large brain Generalize tooth pattern Omnivorous Reproduction favors quality over quantity Arboreal adaptations
primate social charateristics
Most are diurnal
Develop in a social context
Importance of play
development in a social context
Mother-infant bond very important
Harlow’s investigations on isolation
“Aunt” behavior by females in group
importance of play
Practice physical skills
Social relationships
Prosimians
show a lesser degree of primate traits
lemur, lorises, and tarsiers
lemur like forms
Found only in Madagascar and the Comoro Islands Range of body sizes Quadrupeds Vertical clinging and leaping Solitary to large groups (60+ members) Female dominance
loris like forms
Southeast Asia and sub-Saharan Africa
Nocturnal
Avoid other primates
Arboreal
Lorises
Slow quadrupedal locomotion
Bushbabies
Quick vertical-clinging-and-leaping
tarsiers
Philippines and Indonesia Nocturnal Arboreal Insect eaters Vertical clinging and leaping Mated pair and dependent offspring No rhinarium
Anthropoids
old world primates and new world monkeys
Platyrrhines (new world monkeys) traits
Broad, flat-bridged noses Nostrils facing outward Three premolars Prehensile tail Completely arboreal Found only in the New World
Callitrichids (marmosets and tamarins)
Very small Claws instead of nails Give birth to twins Monogamy or polyandry Male care of infants Eat fruit, sap and insects
cebids
Monkey monkeys
Vary widely in size, group composition, and diet
Catarrhines (old world primates) traits
Narrow noses
Nostrils facing downward
Two premolars
Old World monkeys, apes, and humans
old world monkeys traits
Narrow noses
Nostrils facing downward
Two premolars
Colobine Monkeys (OWM)
Asian Langurs, African colobus monkeys Mostly arboreal Leave and seed eaters Pouched stomachs Long intestinal tracts
Cercopithecine monkeys (OWM)
Includes terrestrial specimens Notable sexual dimorphism in some species Depend more on fruit Cheek pouches Ischial callosities
hominoid characteristics
Relatively large brains, especially cerebral cortex
Short, broad trunks
No tail
Skeletal specialization for suspensory locomotion
Some degree of bipedal locomotion
Flat and rounded molars
Blood proteins group chimps, gorillas and humans
Gibbons and Siamangs (lesser apes)
Southeast Asia Specialized brachiators Swing arm over arm Pair bonding Little sexual dimorphism Highly territorial
orangutans
Borneo and Sumatra High degree of sexual dimorphism Body size Cheek pads and throat pouches Arboreal fruit-eaters Solitary
gorillas
Africa Eat stems, shoots, leaves, roots, flowers Large degree of sexual dimorphism Males twice the size of females Sagittal crest (males) Knuckle walking Harem with “silverback” as leader
chimpanzees
Forested areas of Africa Two species Eat significant amounts of meat Group organization seems to vary by location Fusion-fission society Patrilineal and matrilineal groups known “Cultural” behaviors
bonobos
Longer limbs, smaller heads, dark faces, part in their hair
No sexual dimorphism
More social and female centered
hominid/hominin traits
Bipedalism Thumb is longer and more flexible Larger brain size Cerebral cortex Generalized teeth U-shaped dental arch Present of a chin Male-female bonding
hominin behaviors
Tool making Spoken, symbolic language Hunting large animals Completely terrestrial Longest infant dependency period Division of labor
incisors
Cutting
Most primates have 2
Primitive mammalian form is 4
Somewhat procumbent, becoming more vertically oriented through hominid evolution
canines
Function = grasping, tearing
Large canines associated with carnivores
Social function
Diastema
premolars
Function = grinding, sometimes honing Pongids and some monkeys have sectorial 1st premolar Cutting, slicing complex with upper canine Hominids = bicuspid Trend to become more molar like Primitive condition = 4 NWM = 3 OWM, apes, and humans = 2
molars
Function = grinding, crushing Vegetarians have very large molars OWM = bilophodont Four cusps in two parallel rows Hominoids = 5-Y pattern
tooth arch shape
Earliest primates diverged in back
Modern apes = rectangular
Humans = parabolic
molar enamel
Thin in gorillas and chimps
Thick in orangutans and hominids
