National Geographic's Best Photos of 2016

Randy Olson, Sandhill Cranes and Lightning, Nebraska

Philip Toledano, testing a Mars suit in a dust chamber at Cape Canaveral.

Ronan Donovan, Wolves Feeding on a Bison Carcass, Yellowstone

Matthieu Paley, Heart Drawn by a Child in the Sand inside a Train, Kashgar

Charlie Hamilton James, Yoina Mameria Nontsotega and her pet monkey, Peruvian Amazon

Many more here, but be warned that some are very sad