What environmental factor primarily leads to differences in typical group size between Western and Eastern gorillas?

Answer

Availability and distribution of food resources

Western lowland gorillas rely on scattered fruit patches and form smaller groups, whereas Eastern gorillas, like Mountain gorillas, thrive in areas with abundant, distributed terrestrial vegetation, allowing them to sustain much larger aggregations.

What environmental factor primarily leads to differences in typical group size between Western and Eastern gorillas?
classificationgroupPrimategorilla