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1

characterization in the order of primates

primates--> Haplorhini -->apes and monkeys
--> strepsirrhini lemurs and tarsiers

2

primate locomotion

Quadrupedal,
bipedal
knuckle walking
brachiation

3

anthropoid

Monkeys and apes

compared to lemuriformes:

-generally larger body size
-shorter snouts with greater emphasis on vision
-closed orbits (eye sockets)
-less specialized dentition, no comb
-larger and more complex premolars
-derived, square molars
-nails instead of claws
-fuesed mandible

4

prosimian

lemurs, lorises, bushbabie, tarsiers

5

strepsirhini

suborder
leumurs and lorises

6

haplorhini

suborder
tarsiers, monkeys, apes, and humans

7

old world monkeys

Habitat ranges from tropical jungle to semiarid desert to seasonally snow-covered areas
-Cercopithecidae
--cercopithecienes: more omnivorous with cheek pouches, arboreal, mostly found in africa
--colobines: mainly eat leaves
-most are quadrupedal and arboreal
-ischial cllosities, hardened skin on buttocks
-sexual dimorphism

8

new world monkeys

-70 species in a bunch of arboreal environments
-outward facing nostrils
-size, diet and
ecological adaptation vary
-some possess prehensile tails
-all diurnal, except owl monkey
-quadrupedal, except spidermonkeys are semibrachiators
-most live in mixed sex groups of all ages

9

apes

blsa

10

evolutionary trends during cenozoic era

bla

11

y-5 molar pattern

molars that have 5 cusps, oriented in a manner forming a Y-shaped groove pattern on the surface
(apes and humans)

12

bilophodonty

molars that have 4 cusps, oriented in 2 parallel rows. characteristic of old world monkeys

13

mosaic evolution

A pattern of evolution in which the rates of evolution in one functional system vary from those in other systems

e.g bipedality paved the way for brain, behavior, and tool making stuff

14

taphonomy

the study of the decay of organisms over time, and/or fossilization of organic material. Also, patterns of sedimentation and damage done to organic material post-deposition

15

dating methods

they place sites and fossils into a time frame

relative dating
-stratigraphy
-fluorine analysis

chronometric dating
-potassium/argon (k/Ar)
-Carbon- 14
-Thermoluminiscence

other
-tree ring dating
-Biostrataphy

16

stratigraphy

used in relative dating b/c of the law of superpostion stating that a lower stratum (layer) is older than a higher stratum

valuable in reconstructing the history of earth and life

Drawback: disturbances can shift strata and objects making it difficult or impossible to reaconstruct the history

17

experimental archaeology

helps to understand how artifacts wer made and used by reconstructing prehistoric techniques of stone toolmaking, butchering, etc.
-i.e. using direct percussion or pressure flaking to make stone tools

18

bipedalism-origins

origin theories:
ecological influences
-vision model
--better view of surroundings

energy efficiency
-efficient walking
-Thermoregulatory model
--reduces heat gain and increases heat loss

dietary influences
-reach fruit high up in trees

sexual selection and mating influences
-provisioning model
--male provisioning of female and offspring is easier with bipedalism

19

Anatomical trends in the pre-australopithecines and australopithecines

b

20

gracility

reduced muscle attachement and tooth size

21

laetoli

laetoli footprints showed clear evidence that bipedalism preceded enlarged brains in hominins (showing habitual bipedalism came first as it started in australopithecus afarensis)

22

East African vs. South African gracile australopithecines

East african: affarenses

south african: africanus

23

Sahelanthropus tchadensis

A fossil found a while back from a pre-australopith

-named: July 2002
-Location: chad
-Found by: Brunet et al.
-estimated age: 6-7 mya
-cranial remains only
-Dated using index fossils (biostratigraphy)

hominin-like features:
-facially resembles younger species
-small canines

un-hominin-like features:
-Location of foramen magnum
-Brain size: 320-388cc
-U-shaped dental arcade

24

Orrorin tugenensis
"Millenium man"

pre-australopith fossil
-found in 2000
-location: Western Kenya
-Age estimate: 6 mya

hominin-like:
-inferiorly thick femoral neck
-small canines

un-hominin-like:
-Debate about femoral neck
-Brachiation adaptations apparently present

25

Ardipithecus

pre-australopith Genus
-found in NE Ethiopia
- around 5.8 mya but maybe 4.4 mya

mosaic of traits
not referred to as Pan
-Anteiror position of foramen magnum
-Smaller canines, no functioning honing complex
-Postcanine megadontia (not a Pan trait)

Not Australopithecus b/c
-not fully bipedal: opposable big toe, curved phalanges on hands, primitive pelvis, long arms
- Thinner enamel on teeth

26

Australopithecus anamensis

Found at 3 sites at Lake Turkana, Kenya
-4.2-3.9mya
-mix of primitive and derived features
-definitely bipedal (tibia morphology)

gracile

Super hominin
-intermediate dentition (between ARdipithecus and later hominins)
-bipedality based on tibia
-bipedality is not questioned

reasons for Australopithecus
-small body
-small brain
-Prognathism (degree to which face projects in front of braincase)
-Mosaic features (primitive and derived)
-Much too early for it to be Homo

27

Australopithecus afarensis,

All over east africa
-3.9-3 mya
-"Lucy) -40% complete; 3.2 mya
-Brain size: 380-430ccs
-Prognathic face

compared to Pan and Homo:
-Primitive features:
--small brain (380-450cc)
--Prognathic
--Strong nuchral crest
-Derived features
--Intermediate sized canines
-Other key features
--Short legs

-likely highly dimorphic
-bipedal and climbing
-decendent of anamensis

28

Australopithecus africanus

-fossil found in south african rock quarry
-3.5-2.0 mya
-specimen is cmmonly called "Taung Child"
-Estimated to be a five to six years old

Primitive traits:
-Postrcranially similar to A. afarensis

Derived traits:
-less prognathic
-rounded cranium
-Larger brain (450-550 ccs) than A. afarensis

Derived but not human:
-large molars (smaller than later Australopiths)
-Strong lower jaw
-Nasal pillars (only present in southern african)

29

Kenyanthropus platyops

in the genus Australopithecus

30

bipedalism anatomy

-spinous processes reduced
-anterior position of the foramen magnum
-vertebral column s-curved
-Adducted big toe
-Double arch in foot
-Vertebrae larger at base of vertebral column
-Femur angled - puts feet under center of mass
-Wider, "basin-like" pelvis