the curvature of the Earth and the fact that it is tilted slightly on its axis relative to the sun, different regions of the planet receive different amounts of sunlight energy throughout the year. This impacts the length of warm, cold, wet, and dry seasons in these different regions, as well as the temperature, humidity, and other environmental factors that define the region. A biodiversity hotspot is a region containing an exceptional concentration of endemic species, but is threatened by human-induced loss of habitat. These hot spots support nearly 60% of the world’s plant, bird, mammal, reptile, and amphibian species. Many global organizations are working to conserve these biodiversity hotspots, such as the World Wildlife Foundation’s Global 200 and the Critical Ecosystem Partnership Fund. A relatively small number of countries (17) have less than 10% of the global surface, but support more than 70% of the biological diversity on earth. Countries rich in biological diversity and associated traditional knowledge belong to a group known as the Like Minded Megadiverse Countries (LMMC). Read more about LMMC.

Another consequence of the Earth's curvature and rotation is that the hydrologic cycle distributes water differently among these different regions. The result is striking differences in the global distribution of rain and snow (for an explanation of the Hydrologic Cycle, see the Natural Resources chapter). As a result, different regions on the planet have specific sets of environmental conditions, which results in differences in predominant vegetation. Species residing in different regions are characterized by specific adaptations that allow success under the particular set of environmental conditions of the region.