A five-month-old orphaned elephant named "Tembo" plays with his keeper Thomas Chalice, who has nurtured the elephant at Tony Fitzjohn's Mkomazi rhino sanctuary on June 2012 in Mkomazi, Tanzania. (Photo by Chris Jackson/Getty Images)
A massive African Bush Elephant bull shakes his head in indignation. This guy is in musth, a heightened hormonal state leading to increased aggression and sexual drive. I was sitting in an underground research bunker when I took this photo.