U.S. population to top 300 million this month

-- Each American occupies 20 percent more developed land -- housing, schools, shopping and roads -- than 20 years ago.

-- Each American uses three times as much water as the world average; over half the original wetlands in the United States have been lost, mainly due to urban and suburban development and agriculture.

-- Half the continental United States can no longer support its original vegetation; nearly 1,000 plant and animal species are listed by the U.S. government as endangered or threatened, with 85 percent of those due to habitat loss or alteration.

-- The United States consumes nearly 25 percent of the world's energy, though it has only 5 percent of the world's population, and has the highest per capita oil consumption worldwide.

-- Each American produces about 5 pounds (2.3 kilogram) of trash a day, up from about 3 pounds (1.4 kilogram) in 1960; the current rate is about five times that in developing countries.

After U.S. population hit 200 million in 1967, Paul Erlich gained notoriety with a book called "The Population Bomb," which predicted mass starvation due to population growth.