Watch as global population explodes from 300 million to 7 billion.
As NPR's Adam Cole reports, it was just over two centuries ago that the global population was 1 billion — in 1804.But better medicine and improved agriculture resulted in higher life expectancy for children, dramatically increasing the world population.
NPR 的 Adam Cole 報導,就在兩個世紀前,全球人口是1 億—1804 年。更好的藥物和農業技術的提升讓兒童有較高的預期壽命,也極大地提高世界人口的總量。
NPR explains how we reached a population of 7 billion.
Simply put, the world is making babies faster than people are dying, and with improved medicine and agriculture, people are living longer than before. The video above demonstrates the different birth and mortality rates, where each container represents a continent.
There has been a shift in recent years:
Much of that growth has happened in Asia — in India and China. Those two countries have been among the world's most populous for centuries. But a demographic shift is taking place as the countries have modernized and lowered their fertility rates. Now, the biggest growth is taking place in sub-Saharan Africa.
Due in part to that region's extreme poverty, infant mortality rates are high and access to family planning is low. The result is high birth rates and a booming population of 900 million —
a number that could triple by the end of the century.