ACT Reading Practice Test: Humanities and Natural Science

Passage A: Humanities

This passage is from an original personal essay.

[1] The program at the summer music festival listed the piece simply as "John Cage, 4′33″," and the student orchestra performed it without playing a note. The conductor raised his baton, turned the pages of a score that contained no notes, and lowered his arms at the end of each of the work's three movements. For about four and a half minutes, more than sixty musicians sat perfectly still. I remember being annoyed at first, as though someone had played a joke on me and I had paid for the privilege.

[2] Cage composed the work in 1952, and its first performance took place that August in a concert hall near Woodstock, New York. The pianist David Tudor sat at the instrument, closed the keyboard lid to begin each movement and raised it to end each one, and never touched a key. The audience, which had come to hear new music, heard something else: wind moving through the trees outside, then rain on the roof, and finally the murmurs of listeners who began to talk among themselves or walk out.

[3] It is tempting to treat the piece as a stunt, a test of how much an audience will tolerate. Cage insisted that it was nothing of the kind. A year or so earlier, he had visited a room at Harvard University built to absorb sound, expecting to hear total silence. Instead he heard two sounds, one high and one low, and was told that they came from his own nervous system and the circulation of his blood. He concluded that true silence does not exist for a living listener. If that was so, then a "silent" piece was really a frame placed around whatever sounds happened to occur.

[4] That idea changes what it means to listen. At most concerts, the sounds of the hall are treated as interruptions: a cough, a creaking seat, a siren passing outside. In 4′33″, they are the performance. No two performances can sound alike, and the audience is no longer simply receiving the music but helping to make it, whether it intends to or not.

[5] I understood none of this at the festival. What I did understand, somewhere in the second movement, was that I had begun to hear the room. A ventilation fan ticked somewhere above the stage. A child behind me whispered a question and was hushed. Through an open side door came the sound of a car on the gravel lot, slowing and then speeding away. These were sounds I would normally have filtered out without noticing, and now, because I had been given nothing else, I was paying close attention to them.

[6] Critics still argue about whether 4′33″ is music, philosophy or a kind of dare. I no longer think the question matters much. The piece did what good art often does: it took something familiar and made it strange enough to notice. When the conductor lowered his arms for the last time, the audience applauded, and for a moment the applause sounded like part of the piece.

Passage B: Natural Science

This passage is from an original article about insect migration.

[1] Each fall, monarch butterflies in eastern North America set out on one of the longest migrations of any insect. Butterflies from the northern United States and southern Canada head south and west, some covering more than 2,000 miles, until they reach a small number of mountain forests in central Mexico. There they gather by the millions on the branches of fir trees and wait out the winter.

[2] What makes the journey remarkable is that no butterfly completes the round trip. A monarch that emerges in early summer usually lives only a few weeks as an adult, long enough to mate and lay eggs. Butterflies that emerge in late summer are different: they delay reproduction, build up fat, and can live for about eight months. These butterflies fly to Mexico, survive the winter, and start north in spring, but they do not finish the trip. Their offspring, and the offspring of those offspring, carry the population the rest of the way over several generations. The monarchs that fly south the next fall have therefore never seen Mexico.

[3] Without a guide or any memory of the route, a monarch must rely on cues it can sense directly. The most important appears to be the sun. The sun moves across the sky during the day, however, so a butterfly that simply kept the sun at a fixed angle would drift off course as the hours passed. To hold a steady southwest heading, the insect must adjust for the time of day, and that requires an internal clock.

[4] Many researchers expected this clock to be located in the brain, where such clocks are found in many animals. In 2009, however, a research team reported that the monarch's antennae contain clocks of their own that are essential for navigation. When the scientists covered the antennae with black paint, which kept light from reaching them, the butterflies no longer flew in the proper southwest direction. Butterflies whose antennae were coated with clear paint, which let light through, kept their normal heading. The antennal clocks, it seemed, had to receive light in order to work with the sun compass.

[5] The sun is not the only cue. Later experiments indicated that monarchs can also sense Earth's magnetic field, which could serve as a backup compass on days when clouds hide the sun. In tests inside flight simulators, butterflies changed their heading when researchers altered the magnetic field around them.

[6] Understanding these tools matters for more than curiosity's sake. The eastern monarch population has declined sharply since the 1990s, and the forests where the butterflies spend the winter cover only a small area. Knowing how monarchs find their way, and which cues they depend on, could help scientists and conservation planners protect a migration that no single butterfly ever completes but that the species as a whole repeats every year.