The capital of the Kunene region, Opuwo lies in the heartland of the Himba people, a semi-nomadic people who spend their days herding cattle. Long after many of the world’s other indigenous populations had begun to migrate to cities, the Himba had mostly avoided contact with modern culture, quietly continuing their traditional life. But that is slowly changing, with younger generations feeling the draw of Opuwo, where they will encounter cars, brick buildings, and writing for the first time. ... How does the human mind cope with all those novelties and new sensations? By studying people like the Himba, at the start of their journey into modernity, scientists are now hoping to understand the ways that modern life may have altered all of our minds. ... Like an irregular lens, our modern, urban brains distort the images hitting our retina, magnifying some parts of the scene and shrinking others.

Driven by economics (a hunger for resources and new markets) and politics (a longing for strategic allies), Chinese companies and workers have rushed into all parts of the world. In 2000, only five countries counted China as their largest trading partner; today, more than 100 countries do, from Australia to the United States. The drumbeat of proposed projects never stops: a military operating base, China’s first overseas, in Djibouti; an $8 billion high-speed railway through Nigeria; an almost-fantastical canal across Nicaragua expected to cost $50 billion. Even as China’s boom slows down, its most ambitious scheme is still ramping up: With the “One Belt, One Road” initiative — its name a reference to trade routes — President Xi Jinping has spoken of putting $1.6 trillion over the next decade into infrastructure and development throughout Asia, Africa and the Middle East. The scheme would dwarf the United States’ post-World War II Marshall Plan for Europe. ... China’s relationship with Africa goes back to the 1960s, when Chairman Mao Zedong promoted solidarity with the developing world — “Ya Fei La,” as he called it, using the first syllables for Asia, Africa and Latin America. Though it was poor and mired in the chaos of the Cultural Revolution, China won new allies in Africa by finishing, in 1976, a 1,156-mile railroad through the bush from Tanzania to Zambia. Aid continued to trickle in, but there were no other big projects for nearly 30 years