From the time we are children, we ask why. Why can’t I go out and play? Why is the sky blue? Why did my goldfish die? Seeking causes and effects continues into adulthood, so it’s a common method of development. To explain causal relationships successfully, think about the subject critically, gather evidence, draw judicious conclusions, and clarify relationships.

In the following paragraph from “What Pop Lyrics Say to Us Today” (New York Times 24 Feb. 1985), Robert Palmer speculates on the causes that led young people to turn to rock music for inspiration as well as the effects of their expectations on the musicians of the time.

By the late ’60s, the peace and civil rights movements were beginning to splinter. The assassinations of the Kennedys and Martin Luther King had robbed a generation of its heroes, the Vietnam War was escalating despite the protests, and at home, violence was on the rise. Young people turned to rock, expecting it to ask the right questions and come up with answers, hoping that the music’s most visionary artists could somehow make sense of things. But rock’s most influential artists — Bob Dylan, the Beatles, the Rolling Stones — were finding that serving as the conscience of a generation exacted a heavy toll. Mr. Dylan, for one, felt the pressures becoming unbearable, and wrote about his predicament in songs like “All Along the Watchtower.”

Instead of focusing on causes or effects, often writers trace a chain of cause-and-effect relationships, as Charles C. Mann and Mark L. Plummer do in “The Butterfly Problem” (Atlantic Monthly Jan. 1992).

More generally, the web of species around us helps generate soil, regulate freshwater supplies, dispose of waste, and maintain the quality of the atmosphere. Pillaging nature to the point where it cannot perform these functions is dangerously foolish. Simple self-protection is thus a second motive for preserving biodiversity. When DDT was sprayed in Borneo, the biologists Paul and Anne Ehrlich relate in their book Extinction (1981), it killed all the houseflies. The gecko lizards that preyed on the flies ate their pesticide-filled corpses and died. House cats consumed the dying lizards; they died too. Rats descended on the villages, bringing bubonic plague. Incredibly, the housefly in this case was part of an intricate system that controlled human disease. To make up for its absence, the government was forced to parachute cats into the area.