Photograph by Alexandre Turmaine, a MSc student at McGill University

This photograph, taken in central Arizona, pictures a Greater Earless Lizard (Cophosaurus texanus) in the middle of his push-up reps. This brightly coloured reptile marks its territory and asserts its  dominance in front of other males with none other than grueling push-ups in the heat of the desert sun.  When faced with competition, greater earless lizards show off their athletic prowess in a push-up  duel against the trespasser to assess which of the two lizards would potentially win in a battle to the death.  As push-up duels avoid fights that could result in injury, this mutual agreement is beneficial to both individuals.

About the photographer: My name is Alexandre Turmaine, following the completion of my undergraduate studies in  environmental biology, I am starting a masters in the Renewable Resources department at McGill  University studying the foraging success of a cliff nesting seabird (Thick-Billed Murre) using GPS accelerometers.