Kerstin Hinze / Black-bellied hamster (Cricetus cricetus) feeding on yew fruits (Taxus baccata), Vienna, Austria, October.

John Cancalosi / Golden-mantled ground squirrel (Spermophilus lateralis) with very full cheek pouches. Montana, USA, Oct 2010

Wild Wonders of Europe / Wothe / Common hamster (Cricetus cricetus) full with cheeks full, Slovakia, Europe, June 2009

Heather Angel / Bubble eye goldfish (Carassius auratus) with upward pointing eyes and two large fluid-filled sacs.. In captivity, Shanghai Zoo, Shanghai, China.

Kerstin Hinze / Black-bellied hamster (Cricetus cricetus), feeding on yew fruits (Taxus baccata, Vienna, Austria, October.

Kerstin Hinze / Black-bellied hamster (Cricetus cricetus), collecting and feeding on yew fruits (Taxus baccata), Vienna, Austria

Kerstin Hinze / Black-bellied hamsters (Cricetus cricetus) collecting yew fruits (Taxus baccata) on the grass, Vienna, Austria

Kerstin Hinze / Black-bellied hamster (Cricetus cricetus), collecting yew fruits (Taxus baccata), Vienna, Austria, October.

Kerstin Hinze / Black-bellied hamster (Cricetus cricetus) feeding on yew fruits (Taxus baccata) before running away, Vienna, Austria, October.

Kerstin Hinze / European Hamster (Cricetus cricetus), adult with full cheek pouches gnawing a nut, Vienna, Austria. October.

Kerstin Hinze / European Hamster (Cricetus cricetus), adult running with full cheek pouches, Vienna, Austria. October.

Nick Garbutt / Young male Bengal tiger (Panthera tigris tigris) around 20 months (late April 2009) with porcupine quills stuck in cheeks, Tulsi's offspring, Bandhavgarh NP, India

Eric Baccega / Portrait of Goldencheeked Gibbon (Hylobates concolor gabriellae) captive, native to Vietnam, Laos and Cambodia

Lynn M Stone / Male Orang utan portrait {Pongo pygmaeus} captive

John Cancalosi / Male Orang utan portrait {Pongo pygmaeus} captive

Aflo / ic-07501 Siberian chipmunk / Striped squirrel feeding, cheek pouches full {Tamias sibiricus} Japan

Aflo / ic-07405 Siberian chipmunk / Striped squirrel {Tamias sibiricus} Japan

Dietmar Nill / Common tree frog croaking in pond {Hyla arborea} Hungary

Doug Wechsler / Mjoberg's dwarf litter frog {Leptobrachella mjobergi} Bentuang-Karimum NP Indonesia

Niall Benvie / Eastern american chipmunk {Tamias striatus}, feeding on black sunflower seeds, Pennsylvania, USA.

Chris Taylor / Young female toque macaque with full cheeks (Macaca sinica) Sri Lanka

Jim Brandenburg / Will Steger portrait showing nose and cheeks affected by frost bite, North Pole, Arctic