A species of fern can grow in a range of light conditions, and most individuals in a population thrive in medium light. Suppose ferns that thrive in low light become more common over time in the population. Which two sentences must be true for this adaptation to occur through natural selection?
1) The ferns became isolated from other ferns.
2) The ferns developed a mutation that allowed them to thrive in low light.
3) The ferns migrated to an area with low light conditions.
4) The ferns received more nutrients in low light conditions.