A virologist gives the low-down on chikungunya.
Populations revolt when lives are improving but not fast enough to meet their rising expectations.
Edo, which gave rise to Tokyo, was also the world's largest city three centuries ago. Facing ecological collapse, Edo developed a culture and practices that supported sustainable living.
Young Indians have been left desperate by an era of jobless growth.
Air quality in the Indian capital is so bad that the government has instigated a vehicle ban.