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The author of the passage is primarily concerned with
Which of the following best describes the function of the highlighted sentence in the context of the passage as a whole?
Meggers argued that agriculture depends on extracting nutrients from soils into edible crops, so premodern societies in Amazonia could never grow large because underlying soils are impoverished. In Meggers` view the population size that a culture could reach depended upon the agricultural potential of its environment. Meggers accepted that fish and turtle resources of the Amazon made possible the long riverside villages the explorer Orellana described in 1542, but she dismissed as exaggerated Carvajal`s estimates of tens of thousands of people in those settlements, and she was sure those settlements did not have inland counterparts. Supporting this point, the Omagua, a riverbank people and one of the greatest chiefdoms observed by Carvajal as a member of Orellana`s expedition, regarded hinterland forests as unpopulated wilderness.
From the passage it can be inferred that Omagua depended on
The passage mentions the "scandalous memoirs" that were written prior to the Romantic period primarily in order to
Our study revealed that nest‐guarding long‐tailed skinks (a species of lizard) homed (returned to their nests) more successfully when displaced shorter distances. There are two reasons why homing success rates decreased with increasing displacement distance. One possibility is that females were simply displaced too far to find their way home. However, this is unlikely given that some individuals managed to find their way home from each distance we used. The second possibility deals with trade‐offs between the risks associated with making a long return trip and the benefits of returning. Animals should expend energy only when the associated costs are low. As reptiles increase the time spent moving, their daily energy expenditure increases dramatically. The energetic costs of returning home and the chances that the eggs will have been preyed upon during the return trip both increase substantially as displacement distance increases. For example, the 130 hours (5.5 days) that female skinks spent returning from a distance of 300 meters is sufficient for an egg‐eating snake to locate and prey upon the entire clutch. However, females with larger clutches were more likely to home at distances over 50 meters. For these females, the relative fitness benefits associated with having more eggs successfully hatch may outweigh the energetic costs of returning to a nest site, even if the nest may have already been preyed upon.
The primary purpose of the passage is to
The claim in the highlighted sentence assumes which of the following about the individuals that managed to find their way home from each distance?
The "second possibility" implies which of the following as a possible explanation for the female long‐tailed skinks that failed to home from distances over 50 meters ?

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