During the Holocene, the human population has increased from a few million to nearly 8000 million. This expanding human habitat interferes ever more with the natural world, in extent and intensity.

• In early 21^st century, world population is stabilizing as part of a demographic transition, pushed forward by better health, education (of women), income and other factors. It is part of Modernity and is usually assumed to continue;
• Human behaviour plays a crucial role in demographic evolution. Biologists emphasize evolutionary mechanisms, such as the relative roles of cooperation/altruïsm and competition/egoïsm and the coevolution with the environment in niche construction. Social scientists focus more on the role of organization and culture. The ability to interact, work together and communicate explains part of the success of Homo Sapiens;
• Human populations have experienced deep transformations in metabolic regimes, during which human-environment interactions played a key role. Different stages are characterized by archetypical patterns of vulnerability: syndromes. With disposition as indicator of the probability that a syndrome occurs, the exposure and sensitivity determine whether and how the syndrome affects the region. The coping capacity is the capability to prevent or mitigate the consequences;
• Some of the hot topics in relation to population growth, such as birth control, abortion and migration, can best be studied and discussed in a worldview framework.