Thermogram of Tuatara. The Tuatara is a reptile thought to have pre-dated the dinosaurs. The Tuatara in this image was resident at Chester zoo, UK, where in 2016 they reportedly bred the first Tuatara outside of its native New Zealand. The species is said to be extinct in all other places in the world. Reptiles are ectothermic or cold-blooded, changing temperature in reaction to their surroundings.