Chapter 6: From First Primates to First Bipeds

Question 0

bipedalism

Answer 0

A special form of locomotion, distinguishing humans and their ancestors from the African great apes, in which the organism walks upright on two feet, also called bipedality.

Question 1

arboreal adaptation/hypothesis

Answer 1

A theory for primate evolution that proposes that life in the trees was responsible for enhanced visual acuity and manual dexterity in primates.

Question 2

Ardipithecus

Answer 2

One of the earliest genera of bipeds that lived in Eastern Africa. Ardipithecus is actually divided into two species: the older, Ardipithecus kadabba, which dates to between 5.2 and 5.8 million years ago (mya), and the younger, Ardipithecus ramidus, which dates to around 4.4 mya.

Question 3

Australopithecus

Answer 3

The genus including several species of early bipeds from southern and Eastern Africa living between about 1.1 and 4.3 mya, one of whom was directly ancestral to humans. “Taung Child”

Question 4

gracile australopithecines

Answer 4

Members of the genus Australopithecus possessing a more lightly built chewing apparatus; likely had a diet that included more meat than that of the robust australopithecines; best represented by the South African species A. africanus.

Question 5

robust australopithecines

Answer 5

Several species within the genus Australopithecus, who lived from 1 to 2.5 mya in eastern and Southern Africa; known for the rugged nature of their chewing apparatus (large black teeth, large chewing muscles, and a bony ridge on their skull tops to allow for these large muscles).

Question 6

The Leakey family

Answer 6

Discovered bones of the first specimen of the robust Australopithecus boisei in association with some tools and the bones of birds, reptiles, antelopes, and pigs in Olduvai Gorge. Skull and jaw fragments indicated that these specimens represented a larger-brained biped without the specialized chewing apparatus of the robust australopithecines. Named these specimens Homo habilis.