D: Yaël, humans are harming the natural world in pretty obvious ways, such as dumping wastes into the air and water, but could there be ways we are harming other species that are harder to recognize?
Y: Scientists are discovering that there are. Noise pollution is an example. Noise from human activities can disrupt animal behavior, in ways that might put a species at risk of extinction.
D: Do you mean something such as the way too much noise can distract a student from studying and cause them to fail a crucial exam?
Y: Yes. For an animal, attention to sensory cues can be vital to survival. For example, finding the feces of a predator is a warning that the predator itself might still be nearby.
D: Could the sounds of human civilization really distract the animal from a cue that is detected by senses other than hearing?
Y: A team of British scientists showed that they can. The researchers studied the dwarf mongoose, a small African mammal that lives in extended family groups. They put the feces of either a dangerous carnivore, or a harmless herbivore near a mongoose family's burrow. When the animals spotted predator poop they became cautious and vigilant and stayed close to home.
D: Next the researchers would need to introduce some human noise and see what happened.Y: That's right. The scientists put speakers near the animals' burrow, and played either natural sounds or traffic noise. When they played road noise, animals were slower to spot predator poop, and showed less of an increase in caution and vigilance, than when they played familiar natural sounds. If the poop had actually been left by a predator, this could have been a deadly mistake.