Final answer:
The genetic variation within the human species is narrower than that seen in great apes due to a bottleneck effect around 70,000-60,000 years ago.
Step-by-step explanation:
The statement is true. The genetic variation within the human species is indeed narrower than that seen in the great apes. This is because our species has gone through a bottleneck effect around 70,000-60,000 years ago. The bottleneck effect refers to a sharp reduction in the size of a population, resulting in a loss of genetic diversity. In the case of humans, this bottleneck event occurred when a small group of Homo sapiens migrated out of Africa and colonized the rest of the world, leading to a decrease in genetic variation.