Self-study
For a species of large abalone shellfish to develop from a species of smaller ones, they must spend less energy on finding food and avoiding predators, and more on competition in mating. ██ ██ ██ ██████████ ████ ███ ██████ ██████ █████ ████ █ ███████ ██ █████ ████████ █████████ ████ █ ███████ ███ ████ █████ ███████ █████ ████ ██ █████████ █████ ██ ████████ ███ ██████ ██ █████ ███ ████████ ██████
"Surprising" Phenomenon
A larger species of abalones developed from a smaller species only after an abalone predator (otters) began to dominate the abalones’ habitat, despite the fact that the necessary conditions for such a development to occur involve abalones spending less energy on avoiding predators (and finding food).
Objective
The right answer will describe some element of the otters’ domination of the waters that allowed abalones to save energy for competition in mating. This element must either compensate for the extra energy abalones presumably had to spend avoiding otters, or explain why the abalones did not have to spend energy in that way. In either case, the answer must show how the otters’ domination allowed the abalones to save more energy than they had previously.
8.
Which one of the following, ██ █████ ████ █████ ██ ███████ ███ ████████ ███████████ ██ ███ ███████████ ██████
a
Otters and abalones ████ ███████ ███ ███ ████ █████ ██ ████ ███ ██ ███ █████ ██ ███ ████ ███████
This does the opposite of what we need. If the otters’ domination of the water meant that abalones faced increased competition for food, we would expect them to have less energy for competition in mating. We need something that would mean they conserved more energy, not less.
b
The fossils that ████ ███████ ██████ ███ ███████████ ██ ████ ███ ██ ███ ███ ███████ ██ █████ ████████ █████ ██ ██████
This isn’t helpful. It doesn’t matter which species developed—all that matters to us is how.
c
Otters also prey ██ ███ █████████ ███████████ ███ ████ ███ ██ ██████████ ████ ██ ██████ ███ ████████ ██ ███ █████
This explains how otter domination helped abalones conserve energy for competition in mating. The otters ate the abalones’ food competitors, so the abalones were able to use some of the energy that would have otherwise gone to finding food to engage in mating competition instead.
d
Small abalone species ████ ██ █████████ ████ ███████ ████ ██████ ███████ ████████
This doesn’t help us. We’re interested in the conditions that allowed a large abalone species to develop from a small one, not the reproductive tendencies within those separate species.
e
Otters have a ██████████ ███ █████ ████████ ████ █████ ████ ███ ██ ██████ ██████ ██ █████ █████ ████████ ███ ██████
Not only is this unrelated to the development of the larger abalone species, but it also doesn’t make sense with what we know about this habitat. The otters began to dominate when the abalones in these waters were small, which is odd if they prefer waters with large abalones.