The application of evolutionary principles to the study of human variation
a. reinforced traditional views of races as fixed biological entities that do not change.
b. allowed scientists to ignore the adaptive significance of most traits.
c. allowed scientists to divide the human species precisely into well-defined races.
d. helped replace earlier views based solely on observed phenotypes.
e. has been of little value for understanding human variation.
Question 2
A polytypic species
a. is one that has no phenotypic variability.
b. has never been observed in nature.
c. is one composed of local populations that differ from one another with regard to the expression of NO MORE THAN three traits.
d. is one composed of local populations that differ from one another with regard to the expression of ONE OR MORE traits.
e. Is the result of inbreeding.
Eight weeks old human embryo
Human Heart Model
Human embryonic stem cells differentiated to neural cells
muscles human
Major Structures of the Human Brain
Structural comparison of human blood vessels and the direction of blood flow through them