Self-study
Two different dates have been offered as the approximate end point of the last ice age in North America. ███ █████ ████ ███ ███████████ ██ ███████ ██████ █████████ █████ ██ ███████ ██ █████████ ██ █████████ ████ ██████████████ ███████████ ███████ ████████ ████████████ ██████ ████████ ███ ██████ ████ ███ ███████████ ██ ███████ ██████ ██████ ██ █████ ████ ███████ ██ █████████ ████ ███ ██████ ███████ ██ ██████ ████████ ███ █████ ████ ██ ████ ████ ███ █████ ███████ ████ ███ ███████
Summary
Two dates have been proposed as the approximate end point of the last ice age in North America:
First Date: Based on the presence of warmth-adapted open-ground beetles replacing cold-adapted arctic beetles in sediment samples.
Second Date: Based on the emergence of spruce forests as indicated by pollen grains found in the same sediment samples.
The first date (beetles) is over 500 years earlier than the second date (spruce forests).
Strongly Supported Conclusions
Warm adapted beetles appeared before the emergence of spruce forests.
Analysis by Spaulding.Bingaman
7.
The statements above, if true, ████ ████████ ███████ █████ ███ ██ ███ █████████ ███████████ █████ ███ ████ ███ ███ ███ ███ █████████ ██ █████ ████████
a
Toward the end ██ ███ ███ ████ ██████████████ ███████████ ███████ ██████ ██ ███████ █████ █████ ███ ███████████ ████ █████ █████████ ██ ██████ ████████
b
Among those sediments █████████ ██████ ███ ███ ██ ███ ███ ████ █████ █████ ██ ███████ ████████████ ██████ ██████ █████████ ███ ████ ██ ████████ ██ ███████ █████████████ ███████
c
Ice masses continued ██ ███████ ███████ █████ ███████ ███ ███████ ███████ █████ █████ ███ ███ ██ ███ ███ ████
d
The species of ████████████ ██████ ██████ ████ █████████ █████ ███████ ██ ███ ██████ ████ ███ ██████ ███ ███ ██ ███ ████ ███ ████
e
Toward the end ██ ███ ███ ████ ██████████████ ███████████ ███████ █████████ ███ ███ ███████ ██████ ██ ████ ██████ ████ ████ ███████ ███ ████ ██████████ ███████████ ███ ██████ ████████