Self-study
Burying beetles do whatever they can to minimize the size of their competitors' broods without adversely affecting their own. ████ ██ ███ ████ █████████ ███████ ████ ███████ ████ ████ ███ ██ ████ ███████ ███████ ███ ████ ████████ █████████ ████ █████ ███ ████ ██████ ███ ██████ █████ ███ ██ ███ ██████ ████████ ███████ ██ ███ ████ ██ ███ ██████ ███████████
"Surprising" Phenomenon
Burying beetles destroy other burying beetles’ eggs to gain a comparative advantage, so why do they equally care for all the larvae once they’ve hatched?
Objective
The correct answer must draw a distinction between eggs and larvae, since burying beetles attack the eggs of their competitors, but not their larvae. One possibility is that, once the larvae start moving around, they can’t tell the difference between their competitors’ larvae and their own.
25.
Which one of the following, ██ █████ ████ █████ ██ ███████ ███████ ████████ ██████████ █████████████ █████████
a
Burying beetles whose ████ █████ ██████ █████ ████████████ ███ ████ ██████ ██ ████ █████ ██████ ████ ███ ███████ ███████ █████ ████ █████ ██████
This could explain why beetles might want their eggs to hatch earlier than their competitors, but isn’t helpful in explaining why they don’t attack their competitors’ larvae.
b
The cooperation among █████ ███████ ███████ ███████ ████ ███ ████████ ████████ ██████ ██ ██████ ████████
The stimulus establishes that the beetles want to minimize the sizes of their opponents’ broods, so there’s no reason to believe that they would want the greatest possible number of larvae—which would include their competitors’—to survive.
c
Burying beetles are ██████ ██ ████████████ ███████ █████ ███ ██████ ███ ███ ██████ ██ █████ ███████ ████████
This would explain why the beetles attack their competitors’ eggs, but not their larvae. The beetles would probably be unable to avoid adversely affecting their own brood, so they don’t attack any larvae.
d
Many of the ███████ ███████ ██ ███████ ███████ ███ ██ ████████ ████ ██ ███████ ███████ █████████ ██ █████████ ███ ████████ █████
Information about how the beetles defend against other enemies doesn’t help explain why they don’t attack their competitors’ larvae.
e
Most breeding sites ███ ███████ ███████ ███ ███████████ ████ █ ███████ ██████ ██ ███████
If anything, this would make the beetles’ behavior even harder to explain. If space to house larvae is limited, then we would expect the beetles to compete even more intensely for it. This doesn’t explain why the beetles don’t attack their competitors’ larvae.