Juergen Freund / Wildlife carer Margit Cianelli holding Platypus (Ornithorhynchus anatinus) orphan, Atherton Tablelands, Queensland, Australia. Model released.

David Gallan / Platypus (Ornithorhynchus anatinus) surfacing in a pool, Tasmania, Australia, September.

David Gallan / Platypus (Ornithorhynchus anatinus) feeding, Mount Field National Park, Tasmania, Australia, September.

Doug Gimesy / Platypus (Ornithorhynchus anatinus), released onto a log in Little Yarra River, Yarra junction, Victoria, Australia. Photographed under controlled conditions. April 2018.

Doug Gimesy / Platypus (Ornithorhynchus anatinus) in early morning light on Lake Elizabeth, Great Otway National Park, near Forrest, Victoria, Australia, July 2017.

Doug Gimesy / Platypus (Ornithorhynchus anatinus) just released onto a log in Little Yarra River, Yarra Junction, Victoria, Australia. April 2018. Controlled conditions.

Dave Watts / Platypus (Ornithorhynchus anatinus) swimming in lake, Tasmania, Australia.

D. Parer & E. Parer-Cook / Short-beaked Echidna (Tachyglossus aculeatus) foraging for insects, Tasmania, Australia

D. Parer & E. Parer-Cook / Platypus (Ornithorhynchus anatinus) grinding prey between plates of its bill, Atherton Tableland, Queensland, Australia

D. Parer & E. Parer-Cook / Platypus (Ornithorhynchus anatinus) swimming on surface, Atherton Tableland, Queensland, Australia

D. Parer & E. Parer-Cook / Long-beaked Echidna (Zaglossus bruijni) highland forests of New Guinea

D. Parer & E. Parer-Cook / Platypus (Ornithorhynchus anatinus) female swimming in water with courtship bite mark on tail, eastern Australia