1.Why did humans lose the adaptation of a honing canine?
a.It disappeared only after our hominid ancestors began to walk upright.
b.It disappeared because our ancestors acquired the ability to make and use tools for processing food.
c.It disappeared because our ancestors had big enough brains, so they decided that they no longer needed honing canines.
d.That adaptation still exists in the extant human gene pool.
2.Race is not a valid biological concept because
a. races account for only a small amount of biological variation.
b.the ditribution of biological traits follows clines.
c.the frequency and distribution of traits do not agree.
d.all of the above
3.True or False - The US Census methods are a valid way to gauge the ethnicity of people that live in the US.
4.What links have been shown to exist between exercise and brain function?
a.People who exercise more have decreased brain function, because blood is diverted away from the brain during exercise.
b.People who exercise more have increased brain function, because blood flow to all parts of the body, including the brain, is improved by exercise.
c.There is no correlation between exercise and brain function.
d.Exercise was beneficial for our hominid ancestors, but it is not helpful to modern human brain function.