Self-study
In a national park located on an island, a herd of moose was increasing in number and threatening to destroy species of native plants. ██████ ████ ██████████ ██ ███ ██████ ██ ██████ ███ ████ ███ ███████ ███████ ███████████ ██ ███ ███████████ ████████ ███ ██████ ██████████ ███ █████ ████ █████████ ██ █████
"Surprising" Phenomenon
Why did the moose herd continue to grow while the wolves that were supposed to prey on them prospered?
Objective
The right answer will describe some aspect of the environment, the wolves’ behavior, or the moose’s behavior that caused the wolves’ introduction to have little or no negative impact on the moose population’s growth.
12.
Which one of the following, ██ █████ ████ █████ ██ ███████ ███ ███████ ██ ███ ████████ █████████ ███████
a
The presence of ██████ ██ ██ ████ █████ ██ ██████████ █████ █████████ ████ ██████ ████ ███ █████
This doesn’t help. Even if other predators did not move into the area after the wolves were introduced, the wolves themselves are predators, and we would expect the moose herd’s growth to have been impacted by their presence.
b
Attempts to control █████ ███████████ ██ █████ ████████ █████ ██ ███████████ █████████ ████ ████ ████ █████████████
This doesn’t help. We’re looking for the reason why this particular attempt to control the moose population did not work, not other examples of failed attempts.
c
Wolves often kill █████ ████████ ██ ████████ ████ ████████ █████ ████ ██████ ██ █████ ██████
This is what we need. If wolves often kill sick moose, they’re protecting the healthy moose from contracting illnesses which might have otherwise killed off more moose and slowed the population’s growth. Also, the diseased moose the wolves kill presumably would have died anyway.
d
Healthy moose generally ███████ ████ ██████████ ████ ██ █████ ████ ███ ████████ ██ ████████
This is irrelevant. We’re not looking for information about how much vegetation healthy vs. diseased or injured moose eat, and this answer choice tells us nothing about what happened when the wolves were introduced.
e
Moose that are ███ ███ ██ █████ ███ ████ ██ ██████ ██ ███ ██ ███████ ██████ ██ ██ ██████ ██ ███████
We’re not interested in moose that are too old to breed, because the factor we’re examining is population growth. Furthermore, even if older moose are just as likely to die of natural causes, wolf attacks would still presumably kill additional moose, both older and younger.