What makes this award-winning wildlife photograph so powerful?

In Namibia's Huab River Valley, photographer Federico Veronesi captured an elephant carrying a dead calf across a dry riverbed. Christin Winter of Elephant Human Relations Aid says the female is not the calf's mother, but lost her own calf two years ago and has repeatedly carried other elephants' stillborn young.

While researchers debate whether such behaviour shows grief or an elephant's developing understanding of death, jury chair Kathy Moran highlighted the scene's impact: Emotionally it's a gut punch, heartbreakingly poignant. Intellectually it's proof that animals have cognition.

Out of 65,403 entries submitted from around the world, this black-and-white photograph took the competition's top overall title.