Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)

Israeli soldiers detain a protester during a demonstration by Palestinians protesting against the Israeli-built West Bank separation barrier and calling for the right of return for Palestinian refugees, in the northern West Bank city of Tulkarem, on May 31, 2014. (AP Photo/Nasser Ishtayeh)

A participant prepares for the Red Bull Air Race World Championships in Abu Dhabi, United Arab Emirates on February 6, 2017. (Photo by Red Bull Content Pool/SIPA Press/Rex Features/Shutterstock)

A woman walks at the Boulevard of the River the eve of the International Women's Day, in Cali, Colombia, 07 March 2019. (Photo by Ernesto Guzman Jr./EPA/EFE)

Pakistani students look out from a vehicle on their way to school near the Army Public School which was targeted by Taliban militants last year, in Peshawar, Pakistan, Monday, January 12, 2015. (Photo by B.K. Bangash/AP Photo)

Mud Madness at the annual Jaffa Cakes charity three-mile run at Foymore Lodge near Portadown this afternoon, on April 13, 2014. A total of a thousand competitors and fun-runners took part in the two races held over the mudstrewn endurance course. (Photo by Alan Lewis/Photopress Belfast)

A stunning photographic collection featuring portraits of people from 30 countries and the food they eat in one day. In this fascinating study of people and their diets, 80 profiles are organized by the total number of calories each person puts away in a day. Featuring a Japanese sumo wrestler, a Massai herdswoman, world-renowned Spanish chef Ferran Adria, an American competitive eater, and more, these compulsively readable personal stories also include demographic particulars, including age, activity level, height, and weight. Essays from Harvard primatologist Richard Wrangham, journalist Michael Pollan, and others discuss the implications of our modern diets for our health and for the planet. This compelling blend of photography and investigative reportage expands our understanding of the complex relationships among individuals, culture, and food.

An Indian cyclist pedals with a child during heavy rain in Mumbai, Maharashtra state, India, Friday, July 24, 2015. Several parts of the city witnessed heavy rain Friday. The monsoon rains which usually hit India from June to September are crucial for farmers whose crops feed hundreds of millions of people. (Photo by Rajanish Kakade/AP Photo)