Was resource intensification – an increase in labor and time devoted to subsistence activities in order to increase food yields – by Dorset Paleo-Eskimos and Recent Indians on the island of Newfoundland simply a response to population pressure? Not exactly. On Newfoundland, population pressure did not result from a steadily growing resident population but, rather, from the arrival and lingering presence of new and significantly different populations. Newfoundland's hunter-gatherer populations – both resident and newcomer – adjusted to the presence of other populations through niche differentiation. Building on a tradition that emphasized marine resources, Dorset Paleo-Eskimos intensified their harvest of seals in response to the arrival of Recent Indians in the first few centuries A.D. Recent Indians who were more familiar with broad-based, interior-maritime adaptation, intensified this strategy to cope with the Dorset.