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There are several long-term trends concerning humanity. Although these trends might not be observed every day, and there can even be periods and locations contrary to the trends, they still operate on long periods of time.

Longterm Trends

Precession

The inclination of the Earth with respect to the Sun changes in 26,000 year cycles (NASA). The Earth is slowly wobbling on its access. This affects regional climates, including wind, rainfall and temperature. This change can be significant when considering periods of more than a few centuries.

Evolution and Selection

Modern humans have existed for at least 10,000 years. There may not have been much genetic mutation over the past few millennia, so the scope of human evolution during that period may be limited. However, there has likely been some effects due to selection, that is the ability of people to adapt to particular local and social changes ad well as due to mating preferences. For example, during the 1950s-1970s, there was apparently a tremendous mating preference for those who were able and willing to master the electric guitar, an example of a new technology.

Human Population Growth

The human population has grown tremendously in the past 10,000 years (U.S. Census).

Other Trends

• Environmental change
• Climate change
• Species changes (extinction, domestication, monoculture)
• Destruction of forests
• Salinization of soil in irrigated lands
• Total land area used by humans
• Technology advancement

Emergence of Societies

Due to these trends, and arguably the driving force of the eth Law, human societies formed. Living organisms formed,then multi-cell creatures. Animals formed, then vertebrates, then mammals. Primates became smarter and able to use tools. Homo sapiens developed. Language and agriculture were discovered and adopted, allowing people to form complex societies.

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