An employee at Christie's auction house examines a complete sub-fossilised elephant bird egg on March 27, 2013 in London, England. The elephant bird egg is expected to fetch 30,000 GBP when it features in Christie's “Travel, Science and Natural History” sale, which is to be held on April 24, 2013 in London. (Photo by Oli Scarff)

Photographer Gregg Segal travelled the world to document children and the food they eat in a week. Partly inspired by the increasing problems of childhood obesity, he tracked traditional regional diets as yet unaffected by globalisation, and ironically, found that the healthiest diets were often eaten by the least well off. (Photo by Gregg Segal/The Guardian)

A Chinese tourist wears protective gloves as she holds a baby Siberian tiger as they pose for pictures at the Heilongjiang Siberian Tiger Park on August 16, 2017 in Harbin, northern China. The center is one of two Siberian tiger parks in the Chinese province of Heilongjiang, about 500 kilometers (300 miles) from the border with Russia. It is considered the world's largest for breeding the Siberian, or Amur, tiger which is listed as endangered by the World Wildlife Federation. (Photo by Kevin Frayer/Getty Images)

A Ukrainian police officer takes cover in front of a burning building that was hit in a Russian airstrike in Avdiivka, Ukraine, Friday, March 17, 2023. (Photo by Evgeniy Maloletka/AP Photo)

Physicist Arie van't Riet uses a series of duel X-ray cameras to capture flowers, plants and small animals in living dioramas. The x-rays are then finished and colorized in Photoshop. Giving way to some breathtaking nature scenes. Photo: “Chameleon and Begonia”. (Photo by Arie van't Riet)

To most of us, hand-feeding crocodiles might sound like a one-way ticket to a watery grave. But for Jose Eduardo Chaves Salas, 32, coming within inches of the fearsome creatures’ razor-sharp teeth is all in a day’s work. He runs Jose's Crocodile River Tour on the Tarcoles River in Costa Rica, where tourists can watch him feed crocs up to 17 feet long. Photo: A tour guide shows a thumbs up as he sits on top of a crocodile on the Tarcoles river in Tarcoles, Costa Rica. (Photo and caption by Barcroft Media)