John Cancalosi / Great horned owl (Bubo virginianus) chick stretching its wings in nest in a Saguaro (Carnegiea gigantea), is groomed by its parent, Sonoran Desert, Arizona, USA, May.

Ingo Arndt / Japanese macaque being groomed in hot thermal spring {Macaca fuscata} Joshin-etsu NP, Japan

Fiona Rogers / Japanese Macaque (Macaca fuscata) female being groomed, Jigokudani Monkey Park, Japan

Anup Shah / Western chimpanzee (Pan troglodytes verus) young male 'Jeje' aged 13 years being groomed by young male 'Peley' aged 12 years, Bossou Forest, Mont Nimba, Guinea. January 2011.

Anup Shah / Olive baboon (Papio cynocephalus anubis) female with baby aged 1-3 months being groomed, Masai Mara National Reserve, Kenya, September

Fiona Rogers / Bornean Orangutan (Pongo pygmaeus wurmbii) age 3-6 months being groomed by it's mother 'Gina'. Camp Leakey, Tanjung Puting National Park, Central Kalimantan, Borneo, Indonesia. June 2010. Rehabilitate...

Petra Wegner / Bearded Collie, with coat groomed for show, sitting on grass, and wind blowing coat.

Bence Mate / Two newly fledged burrowing owl chicks (Athene cunicularia) one being groomed by its mother (far left) Pantanal, Brazil. WINNER: Eric Hosking Award portfolio image 4/6 - Wildlife Photographer of the Y...

Miles Barton / Close up of sleeping Japanese macaque being groomed, Japan

Anup Shah / Eastern chimpanzee (Pan troglodytes schweinfurtheii) infant make 'Google' aged 5 years being groomed . Gombe National Park, Tanzania. September 2014.

Anup Shah / Olive baboon (Papio anubis) female with a baby aged about 3 months being groomed. Gombe National Park, Tanzania.

Anup Shah / Olive baboon (Papio anubis) young male being groomed on the shores of Lake Tanganyika. Gombe National Park, Tanzania.