Chapter 10: Early Hominid Origins: The Roots of Humanity

Lucy at Hadar

- (type specimen) is very complete skeleton recovered at Hadar. - Bipedal, may have had stride similar to modern humans' - Long arms, curved finger bones, suggesting tree use

Australopithecus afarensis (3.6-3.0 mya) are?

- An East African Australopithecus -

Ardipithecus kadabba characteristics?

- An early pre-Australopithecus species - Bipedal (toe bone) - Perihoning complex (intermediate between honing and non-honing)

Footprints at Laetoli:

- At Laetoli footprints of three hominids - Lived in varied habitats

Orrorin tugenensis:

- East Africa - Femur indicative of bipedalism - Curved hand suggesting time spent in trees.

What is the Provisioning Hypothesis?

- Freeing the hands was important in allowing males to assist females more efficiently in procuring food

Australopithecus robustus is found is South Africa and has characteristics of what?

- Large premolars, molars, with large face and sagittal crest.

East Africa (both with robust traits)

- Larger back teeth - Sagittal crest for attachment of chewing muscles - Dietary focus on harder foods

Aridpithecus:

- Two species of genus Ardipithecus - Aramis site Two examples: 1)Ardipethcus Kadabba 2) Ardipethecus Ramidus

What Is a Hominid? Characteristics?

1) Bipedal locomotion: getting around on two feet. 2) Nonhoning chewing: No Slicing. Mainly grinding.

What is the Patchy Forest Hypothesis?

1) Bipedalism - greater efficiency in some habitats of moving on two limbs 2) Bipedalism arose in areas where forests were fragmented and food resources also became scattered. 3) Bipedalism freed the hands to pick up food allowing for both tree and ground food resources to be exploited.

Charles Darwin's Hunting Hypothesis

1) Bipedalism freed hands for carrying weapons. 2) Intelligence increased; size of canines diminished. 3) Tool production and use essential for development of human intelligence.

"Robust" Australopithecines characteristics?

1) Larger molars, powerful jaws, sagittal crest. 2) Not earlier than the less "gracile" types.

By 3 mya two lineages of hominids emerge reflecting multiple adaptations, what are they?

1) Lineage associated with origin and evolution of genus Homo. Continues to present. 2) Later Australopithecine lineages descended from earlier A. afarensis

The Australopithecines has two genera and variation mostly in size and robusticity as well as:

1) Small and gracile 2) Large and robust

Australopithecus anamensis located in east Africa and date to 4mya are physically somewhat similar to___________?

Ardipithecus

Much of difference between "gracile" and "robust" involve

Facial structure - jaw , teeth, chewing muscles.

East Africa Contexts includes

Great Rift Valley (sites in Ethiopia and Tanzania for examples)

Australopithecus sediba found in south Africa on the Malapa site and is has a more what?

Homo-like pelvis

South Africa Contexts:

Limestone areas.

Paleolithic or Old Stone Age. The Oldowan tools belong to the first part of the__________?

Paleolithic

SOUTH AFRICA: Australopithecus africanus was first found by_______ and was found at________, South Africa?

Raymond Dart, Taung

Group characteristics of Australopithecines include:

Small brains

Who Were the First Hominids?

The Pre-Australopithecines (found only in Central and East Africa)

Australopithecus garhi are the first makers and users of?

Tools . (More humanlike humerus-to-femur ratio.)

Sahelanthropus tchadensis is the oldest possible ______ _______ to genus Sahelanthropus.

bipedal hominid