- 7.2 billion people inhabit the Earth as of 2014, according to the U.S. Census Bureau. By 2050, the population is expected to total between 8.3 and 10.9 billion. - 75% of Earth's land surface outside of ice sheets is managed by humans. - 40% of Earth's land area is used for agriculture. As population has increased, demand for food has skyrocketed. - 50% of the world's forests have been lost. - Extinction rates are now 100 to 1,000 times above normal, or background, levels. - 10% of the world's land area is protected