Self-study
The number of deer living in North America has increased dramatically since the 1960s even though hunters kill no fewer deer today. █████████ ███ ██████ ██ ███████ █████████ ██ █████ ████ ██ ███████ ██ ██ ███ █████ ███ ███████ ████████████ ████████ ██ ████ █████████
"Surprising" Phenomenon
Why has the number of deer in North America increased significantly since the 1960s, even though the total amount of deer killed by hunters has not increased, the number of natural predators of deer has increased, and suburbs are increasingly overlapping with deer habitats?
Objective
The correct answer should tell us something different between the 1960s and today that might lead to more deer today. The correct answer can’t just minimize the effect of natural predators or the encroaching suburbs, because that wouldn’t explain an increase in deer population.
15.
Which one of the following, ██ █████ █████ ████ ████ ██ ███████ ███ ████████ ███████████ █████████ ██████
a
Pesticides that adversely ████████ ████ ████████ ██████ ██ █████ ███████ ████ ████ ██████ █████ ███ ██████
Something has changed since the 1960s that’s beneficial for deer. Deer may have been harmed by pesticides in the 1960s. Today, there’s reason to think they’re not harmed by those pesticides. This is the only answer that tells us something might be better for deer today.
b
Recently, attempts have ████ ████ ██ ███████ █████ ██ █████ ███████ ██ ███████ ████ ████████ ████ ████████ ████████████
This might suggest that encroachment on deer habitats isn’t as significant as it theoretically could be. But that doesn’t explain an increase in deer population. We’d still expect a decrease because of the encroachment and the increase in predators.
c
The number of ████ ███████ ██ █████ ███████ ███ █████████ █████ ███ ██████
The stimulus already tells us the total number of deer killed by hunters is the same. So, the number of deer hunters doesn’t matter. Even if there are fewer deer hunters, that would just mean each deer hunter is killing more deer.
d
Much of the ████████ ██ ███ ██████████ ██ ██████ ██ ███ ██ ██████ ████ ██ █████████ ███ ████████ ████ ███ █████
The origin of the increased wolf population doesn’t help explain an increase in the deer population. Even if you assume these formerly captive wolves aren’t as good hunters as wild wolves, we’d still expect an increase in wolves to contribute to a decrease in deer population.
e
The greater the ██████ ██ █████ ███ ████ ██████ ████ ███ ██ ██ █████████ ████ ████████ ████ ██ ██████ ███ ████████
This tells us something negative about greater numbers of dear. This makes it harder to explain why the deer population has increased.