The horned lizard is camouflaged, spiky and can inflate itself like a pufferfish. But just in case that isn’t enough to deter predators, it has one last defence to deploy. By closing off certain blood vessels, the horned lizard abruptly increases the blood pressure in its head. This ruptures capillaries near the corners of its eyes and a jet of blood squirts from each, as far as 1.5 metres (five feet). In a single squirt, the lizard can lose a third of its total blood. Texas horned lizards eat Maricopa harvester ants, which have the most toxic venom of any insect. But far from poisoning the horned lizard, these toxins are stored and injected by special glands into the liquid projectile to cause a nasty burn.