A _________________ is a bony ridge on top of the skull to which chewing muscles attach.
a. Molar.
b. Brow ridge.
c. Sagittal crest.
d. Jaw bone.
Question 2
The fossil evidence indicates that one of the oldest known hominid species, Ardipithecus ramidus, existed over_________ years ago.
a. 4.4 million.
b. 1.8 million.
c. 2.4 million.
d. 1.5 million.