Before the 800-year period studied, the average body size of northern fur seals fluctuated dramatically. Hunting by Native peoples in North America did not significantly reduce the northern fur seal population over the 800-year period studied. During the 800-year period studied, seal hunting practices did not vary substantially between different groups of Native peoples in North America. Native peoples in North America made an effort to limit their hunting of northern fur seals in order to prevent depletion of seal populations.
The size of northern fur seals provides a reliable indication of their population levels -- the smaller the average body size of seals in a population, the larger the population. Archaeologists studied seal fossils covering an 800-year period when the seals were hunted for food by Native peoples in North America and found that the average body size of the seals did not vary significantly.
The statements above, if true, provide the most support for which one of the following?