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While marine hermit crabs are well known for being omnivorous filter feeders, less is known about the role they may play as active camion scavengers in intertidal ecosystems. Prior studies have revealed that intertidal hermit crabs can be attracted to chemical cues from gastropods(snails) killed by predators. Yet their attraction is usually assumed to be driven primarily by the availability of new shells for shelters rather than by food. Researchers conducted field experiments to assess hermit crabs' potential role as generalist carrion scavengers on the California coast, examining their speed of attraction and the size of the aggregations they formed in response to chemical cues from freshly smashed gastropods and mussels both of which indicated available carrion. Compared to all other marine species, hermit crabs were the fastest to arrive at the provisioning sites. Hermit crabs also dominated the provisioning sites, accumulating in the largest numbers, with aggregations of up to 20 individuals, which outcompeted all other scavengers for carrion. Notably, hermit crabs arrived equally quickly for both smashed gastropod and mussel, even though the latter does not offer suitable shells for hermit crabs and even though the former only yields shell-related chemical cues over time frames longer than the experiments. These results thus suggest that shell availability is not the only, or even the primary reason marine intertidal hermit crabs aggregate at carrion sites; they also aggregate to forage, thereby playing an important role as active carrion scavengers in intertidal ecosystems.
The highlighted sentence primarily serves to
It can be inferred from the passage that the findings from the "field experiments "shed new light on which of the following issues related to hermit crabs?
Which of the following can be inferred from the passage about gastropod carrion?
The passage is primarily concerned with
Carolyn took out a one-year loan for $15,000 at 8 percent simple annual interest. She repaid the total amount, including the interest, by making 12 equal monthly payments on the last day of each month beginning in January. At the beginning of which of the following months did Carolyn have less than $10,000 of the total amount left to the repaid?

Indicate ALL such months.
If $$x \geq 0$$, $$y \geq 0$$, and $$x^{2}$$+$$y^{2}$$=$$1$$, which of the following statements must be true?

Indicate all such statements.
$$x-y \gt x$$ and $$x+y \lt y$$

Quantity A

$$x$$

Quantity B

$$y$$


If xy ≠ 0, which of the following is equivalent to $$y^{-1}=3x^{-1}$$?

Quantity A

The number of integer solutions of the equation $$3x^{2}+5x-2=0$$

Quantity B

1




It is common to quote David Hume arguing against the possibility of reasoned ethics--for example, his observation that "the rules of morality ... are not conclusions of our reason." Hume's remarks on the relation between reason and ethics are so myriad that it would be presumptuous to seek a definitive clarification of his position. But it is worth noting that immediately preceding the remark just quoted, Hume declares: "Morals excite passions, and produce or prevent actions. Reason of itself is utterly impotent in this particular.” The qualification "of itself" is important to note. This is, in fact, not an argument that reason is unimportant for morality or for motivating action. It argues only that reason cannot accomplish this entirely on its own.
The primary purpose of the passage is to
The author quotes Hume in the first sentence of the passage primarily to
Stannard may be hoping to resurrect Spark's literary reputation with this book, given its ____________ praise for her creative talents.
An engineer draws two concentric circles on a blueprint. If the diameter of the outer circle is 6 centimeters greater than the diameter of the inner circle, how much greater, in centimeters, is the circumference of the outer circle than the circumference of the inner circle?


In the xy-plane shown, what is the maximum distance from an endpoint of line segment AB to a vertex of triangle DEF?
Pat has five matched pairs of socks and no two of the pairs are the same color. If Pat selects two socks simultaneously and at random, what is the probability that the two socks selected will be a matched pair?
There has been a noticeable reversal from the time when (i)____________ was accepted as the essential characteristic of genuine science: now the role of (ii)____________ in scientific research is generating a great deal of interest.
That the announcement of the new treatment was greeted with ___________ is hardly surprising given the claims made for it, but attitudes were markedly tempered once the paucity of supporting data became apparent.

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