TEXT E
Human’ s
Hands Archaeological records--paintings, drawings, and drawings
of humans engaged in activities involving the use of hands--indicate that humans
have been predominantly right - handed for more than 5,000 years. In ancient
Egyptian artwork, for example, the fight-hand is depicted us the dominant one in
about 90 per- cent of the examples. Fracture or wear patterns on tools also
indicate that a majority of ancient people were fight - handed.
Cro - Magnon cave paintings some 27,000 years old commonly show outlines
of human hands made by placing one hand against the cave wall and applying paint
with the other. Children today make similar. out- lines of their hands with
crayons on paper. With few exceptions, left hands of Cro-Manganese are displayed
on cave wails, indicating that the paintings were usually done by
right-handers. Anthropological evidence pushes the record of’
handedness nearly human ancestors back to at least 1.4 million years ago. One
important line of evidence comes from flaking patterns of stone cores used in
toolmaking: implements flaked with a clockwise motion (indicating a right
-handed toolmaker) can be distinguished from those flaked with a counter-
clockwise rotation (indicating a left- handed toolmaker). Even
scratches found on fossil human teeth offer clues. Ancient humans are thought to
have cut meat into strips by holding it between their teeth and slicing it with
stone knives, as do the present - day Inuit. Occasionally the knives slip and
leave scratches on the users’ teeth. Scratches made with a left - to - right
stroke direction (by right- handers) are more common than scratches in the
opposite direction (made by lefthanders). Still other evidence
comes from cranial morphology: scientists think that physical differences
between the right and left sides of the interior of the skull indicate subtle
physical differences between the two sides of the brain. The variation between
the hemispheres corresponds to which Side of the body is used to perform
specific activities. Such studies, as well as studies of tool use, indicate that
right - or left - sided dominance is not exclusive to modern Homo sapiens.
Populations of Neanderthals, such as Homo erects and Homo habilis, seem to have
been predominantly right -handed, as we are. All of the following are mentioned as types of evidence concerning handedness EXCEPT______.
A.ancient artwork B.asymmetrical skulls C.studies of tool use D.fossilized hand bones