Using palynological data, Haynes and Mehringer concluded that the climate at the Lehner Clovis site in southeastern Arizona 11,000 years ago was
a. only slightly wetter and cooler than today, followed by a rapid shift toward drier conditions.
b. only slightly drier and warmer than today, followed by a rapid shift toward wetter conditions.
c. much drier and warmer than today; only a large shift in temperature and precipitation would have caused such a different environment at the site.
d. much wetter and cooler than today; only a large shift in temperature and precipitation would have caused such a different environment at the site.
e. much drier and colder than today; only slight shifts in temperature and precipitation would have cause a stationary environment at the site.
Question 2
What do fluctuations in pollen percentages in a pollen diagram indicate?
a. Changes in frequencies of animal remains present at a site.
b. Changes in the types of domesticated plants that prehistoric populations relied upon.
c. Changes in local and regional plant densities.
d. Climatic change in the form of decreasing temperatures and increasing moisture content.
e. Ineffective measurement devices, since pollen percentages do not fluctuate.
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