What are the environmental implications of changing household sizes? A recent article by Mason Bradbury, M. Nils Peterson, and Jianguo Liu, published in Population and Environment, analyzes data from 213 countries over 400 years and finds the average number of occupants per home tends to decline as population grows. This dynamic, they write, indicates that accommodating housing could prove to be one of “the greatest environmental challenges of the twenty-first century.” As countries develop and urbanize, “according to convergence theory, household size decreases (often from greater than five to less than three).” Other cultural shifts, like increasing divorce rates, urban sprawl driven by rising affluence, decreasing numbers of multigenerational households, and larger houses (in the United States, homes more than doubled in size between 1950 and 2002, according to the article) compound the issue. As population growth continues in parts of the world, these trends pose critical questions for conservation and environmental sustainability, since “households are the end consumers of most natural resources and ecosystem services.”

The pork industry in China accounts for 65 percent of domestic meat consumption, but also produces 1.29 billion metric tons of waste every year. China’s growing appetite for meat has put tremendous pressure on the livestock sector, which now produces three times more waste than industrial sources, and created a series of environmental and food safety issues.

How has China managed to feed nearly one-quarter of the world’s population with only seven percent of the world’s arable land?

In 1995, Lester Brown forecasted doom and gloom for China’s ability to produce enough grain for its people, in his popular book, Who Will Feed China? He hypothesized that China would be forced to buy grain from abroad, thereby seriously disrupting world food markets.

In the wake of natural disasters, the idea that systematic change might be needed to prevent future crises often takes a backseat to restorative efforts. But as disasters become more common, there is often a blurring of disaster response and development initiatives.

This past December, Bangladesh turned 42, bringing the country Henry Kissinger once predicted would become a “basket case” into comfortable middle age (though perhaps this analogy breaks down for countries like Switzerland, age 722).

The original version of this article, by Susannah Fisher, appeared on the International Institute for Environment and Development.

Nepal’s vulnerability to a warming climate became clear in May 2012 when the Seti River burst its banks during flash floods and landslides that killed more than 60 people. Scientists say such events are likely to become more common as the world warms, so communities need to adapt.