Morley Read / Slow motion clip of a Linnaeus' sipo snake (Chironius exoletus) with open mouth, part of threat display, Amazon rainforest, Orellana Province, Ecuador. (non-ex)

Morley Read / Parrot snake (Leptophis ahaetulla) threat display, Amazon rainforest, Orellana Province, Ecuador. (non-ex)

Robert Valentic / Heath Monitor (Varanus rosenbergi) male enacting a threat display, in mallee/heath habitat near Pinnaroo, South Australia.

Silke Arndt / Western rattlesnake (Crotalus viridis viridis), threat display, South Dakota, USA, September.

Ingo Arndt / Hamadryas baboon male threat display {Papio hamadryas} Africa

Ingo Arndt / Gelada baboon males threat display {Theropithecus gelada} Simien Mt NP, Ethiopia

Ingo Arndt / Gelada baboon male threat display {Theropithecus gelada} Simien Mt NP, Ethiopia

Ingo Arndt / Prairie rattlesnake (Crotalus viridis viridis), threat display, South Dakota, USA September. Sequence 1 of 3

Richard Du Toit / Ostrich (Struthio camelus) male in threat display, Rietvlei Nature Reserve, South Africa

Thomas Marent / Lion-tailed Macaque (Macaca silenus) in threat display, Western Ghats, India

Nick Upton / European robin (Erithacus rubecula) standing upright in a territorial threat display in a meadow among patchy snow, Wiltshire, UK, January.

Christophe Courteau / Gelada Baboon (Theropithecus gelada) dominant male threat display, lip curl, Simien NP, Ethiopia, 3000m altitude