Adapted from "Humming-Birds: As Illustrating the Luxuriance of Tropical Nature" in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878) The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, "All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me." Which of the following inferences does the passage expect its readers to make?
A. If a hummingbird eats gnats, it will not eat honey.
B. The author is the first scientist to ever have investigated what hummingbirds eat.
C. Scientists rarely learn about hummingbirds by dissecting them.
D. If a hummingbird consumes flower nectar, this nectar will turn into the honey that can be found in its stomach.
E. Fly-catchers are a type of insect.
Correct Answer: D
Explanation/Reference:
Explanation:
Let’s consider each of the answer choices to identify the correct one. "The author is the first scientist to ever have investigated what hummingbirds eat." – This cannot be true, because the author begins the passage by saying "The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects." He also cites numerous other scientists’ opinions throughout the passage, so he can’t be the first person to have investigated what hummingbirds eat.
"Fly-catchers are a type of insect." – The passage mentions fly-catchers in the following sentence: "Many [hummingbirds] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig." This is a tricky answer choice in that it’s easy to misread the sentence and think that "just like flycatchers" refers to "other small insects" when in fact it refers to the act of "catching." The sentence is saying that hummingbirds catch insects in the same manner as fly-catchers, not that fly-catchers are a type of insect. Plus, we are being asked to identify an inference readers are expected to make, and if this sentence did mean that fly-catchers were insects, it would be overtly telling us this, and there would be nothing we’d have to infer.
"Scientists rarely learn about hummingbirds by dissecting them." – This answer choice is proven wrong by the following sentence: "Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey." "If a hummingbird eats gnats, it will not eat honey." – Given that the questions of whether hummingbirds eat insects or honey and in what proportions is the topic of the passage, it may be easy to choose this answer choice because it seems like the one closest to the passage’s main idea; however, nothing in the passage supports this assertion. "If a hummingbird consumes flower nectar, this nectar will turn into the honey that can be found in its stomach." – This is the correct answer! The author initially states that "All the early writers down to Buffon believed that [hummingbirds] lived solely on the nectar of flowers"; however, he later states that "Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey." The author does not address the idea that flower nectar andhoney could be different substances, and instead expects the reader to treat these as one source of food.
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