David Tipling / Common European adder (Vipera berus) two males fighting over a female. Holt, North Norfolk, England, UK. April

David Tipling / Common European adder (Vipera berus) two males fighting over a female, Holt, North Norfolk, England, UK. April

David Tipling / Common European adder (Vipera berus) two males fighting over a female, Holt, North Norfolk, England, UK. April.

Ingo Arndt / Dwarf puff adder / Sidewinder snake crossing sand {Bitis peringueyi} Namibia

Alex Hyde / Adder (Vipera berus) basking amongst bracken fronds. Peak District National Park, Derbyshire, UK. April.

Paul Harris / 2020VISION / Local resident Roy Peters holding two Adders (Vipera berus) male in foreground female behind, Caesar's Camp, Fleet, Hampshire, England, UK, May 2011. Model released.

Danny Green / Male Adder (Vipera berus) tasting the air. Cannock Chase, Staffordshire, UK, October.

Laurie Campbell / Male Adder (Vipera berus) basking on rock, Northumberland National Park, England, May

Klaus Echle / Black Viper / Adder (Vipera berus) head in profile. Black Forest, Germany, June.

Colin Varndell / Adder (Vipera berus) basking on pebble beach. Abbotsbury, Dorset, UK, March.

Juergen Freund / Researchers Guido and Katja Westhoff work in a mobile lab in the bush. To handle the deadly Common death adder (Acanthophis antarcticus) Guido puts the head and upper portion of the snake in a plastic...

Juergen Freund / Researchers Guido and Katja Westhoff catching a highly venomous Common death adder (Acanthophis antarcticus) found 10 minutes into their group's evening road collection. The death adder ranks 9th out...