Past and future population growth, conceptual image. Illustration of a timeline of population growth, with dates down left, and human figures (blue) representing population growth, and tree images, representing nature. Over time, nature is replaced by humans. The population figures are down right, from 5 million years ago to 2100. The Earth's population grew rapidly in the 20th century due to increased healthcare, reduced infant mortality and increased life expectancy. In the early 21st century, the world population is over 6 billion, and it is thought the global population could reach nearly 10 billion by 2050, and over 11 billion by 2100. The human population may exceed the available resources, as well as severely impacting the natural environment and ecosystems, triggering mass extinctions of species. |