A study question tests what conclusion you can draw from the researchers' results. When the study tracks more than one stage, record each group's result at each stage so an early result isn't mistaken for a later one. Ask what changed between groups, because a cause shared by both can't explain their difference. Use those differences to draw a conclusion that fits every stage without adding claims. A choice can sound reasonable but go past what the researchers measured.
Hints
- Hint 1
Look for what the ecologists measured at each stage: what happened after the tides, then what happened through midsummer.
- Hint 2
Compare the replicas with both other groups. What do the replicas share with the live clumps, and how do they differ from bare sediment?
- Hint 3
For the survival comparison, separate what stayed alike from what changed. Your conclusion also has to account for how many seeds were caught earlier.
Step-by-step
Compare trapping and survival
Step 1Track the three groups
The ecologists released equal numbers of marked cordgrass seeds beside live clumps, resin replicas, and bare sediment. What happened after the tides? Clumps and replicas trapped similarly high numbers of seeds, while bare areas retained few. The hypothesis must explain why both clumps and replicas gathered seeds, and it must fit what happens next.
- Step 2
Find what gathers the seeds
What can the replicas do that bare sediment can't? The resin replicas matching the clumps' stem arrangement have the adults' shape without being living plants. Their success suggests that this shape catches seeds as tides pass. So rings can start with seeds getting caught around stems, without a living adult helping them take hold.
- Step 3
Test the later survival result
Does that seed buildup mean the adults help seedlings survive? Among seeds that sprouted, survival through midsummer was lower beside live clumps than beside replicas. With comparable soil moisture and salinity, both places had similar water and salt levels, so those can't explain the gap. The live clumps instead had substantially less light, which could explain the loss. So collecting seeds didn't mean helping seedlings survive.
- Step 4
Keep the hypothesis within the results
What hypothesis avoids taking the rings as proof that the adults facilitate seedling establishment? Passive capture means the adults' structure catches seeds without actively helping them grow. In the choice using that phrase, can arise names a possible source of the rings, not the only source, and even though allows for lower survival afterward. Choice B.