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

Doug Gimesy / Platypus (Ornithorhynchus anatinus) researcher taking cheek pouch samples from an anaesthetized platypus that was captured earlier from in the Snowy River, Dalgety, NSW, Australia. Dalgety, NSW, Austr...

Doug Gimesy / Platypus (Ornithorhynchus anatinus) researcher taking cheek pouch samples from an anaesthetized platypus, Snowy River, Dalgety, NSW, Australia. Dartmouth, Victoria, Australia. May 2018. Model relea...

Doug Gimesy / Platypus (Ornithorhynchus anatinus) researcher taking a cheek pouch samples. Dartmouth, Victoria, Australia . May 2018. Model released

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.