Alex Mustard,Alex Mustard / Whaleshark (Rhincodon typus) swimming and filtering fish eggs from the water. A behaviour known as ram-feeding. Isla Mujeres, Quintana Roo, Yucatan Peninsular, Mexico. Caribbean Sea.

Patricio Robles Gil / Bighorn sheep (Ovis canadensis) ram grazing in snow, Wind River Range, Wyoming, USA, January

Sebastian Kennerknecht / Bighorn Sheep (Ovis canadensis) ram browsing in winter, Lamar Valley, Yellowstone National Park, Wyoming

Alex Mustard / Whale shark (Rhincodon typus) ram feeding in very shallow, plankton rich waters of La Paz bay. La Paz, Baja California Sur, Mexico. Sea of Cortez, Gulf of California, East Pacific Ocean.

Connor Stefanison / Rocky mountain bighorn sheep (Ovis canadensis) ram eating grass, Jasper National Park, Alberta, Canada. December.

Will Watson / Welsh Mule ewe, crossbred sheep for prime meat production from a Bluefaced Leicester ram, with two new born lambs suckling in a pen, Herefordshire, England. April

Brent Stephenson / Soay sheep (Ovis aries) ram feeding amongst flowering bluebells (Hyacinthoides non-scripta). Lundy, Devon, United Kingdom. May.

Brent Stephenson / Soay sheep (Ovis aries) ram feeding amongst flowering bluebells (Hyacinthoides non-scripta). Lundy, Devon, United Kingdom. May.

Brent Stephenson / Soay sheep (Ovis aries) ram feeding amongst flowering bluebells (Hyacinthoides non-scripta). Lundy, Devon, United Kingdom. May.

Mark MacEwen / Burmese long tailed macaques (Macaca fascicularis aurea) using stone tools to open cockles at low tide, Kho Ram, Khao Sam Roi Yot National Park, Thailand.

Mark MacEwen / Burmese long tailed macaque (Macaca fascicularis aurea) using stone tools to open Oysters at low tide, Kho Ram, Khao Sam Roi Yot National Park, Thailand.

Mark MacEwen / Burmese long tailed macaque (Macaca fascicularis aurea) on beach feeding on cockles cracked opened using stone tools at low tide, Kho Ram, Khao Sam Roi Yot National Park, Thailand.