Final answer:
The population of black peppered moths increased in the late 1800s due to less predation. Darker colored moths, better camouflaged against the darkened trees caused by industrial pollution, were less vulnerable to predators.
Step-by-step explanation:
The population of black peppered moths increased in the late 1800s due to less predation. As the Industrial Revolution caused trees to darken from soot, darker colored peppered moths were better camouflaged than lighter colored ones, making them less vulnerable to predators. This selective predation by birds led to an increase in the number of dark-colored moths in the population.