A lizard known as the thorny devil, found in Australia, has an unusual way of staying hydrated in its desert environment: The animal collects morning dew from sand using its skin, a new study shows.
To harvest dew, the thorny devil burrows its body into damp sand, “almost like making a sand angel,” says Falk Esser, a biologist at the University of Freiburg in Germany. The lizard’s body is covered in spiky scales. Between the scales are tiny grooves. Any moisture that touches the animal’s body is collected in these channels. They act like drinking straws to funnel the water toward the lizard’s mouth.
The thorny devil’s thirst-quenching trick relies on capillary action, which causes liquids to move through narrow spaces. This phenomenon occurs when a liquid’s molecules interact with one another and surrounding surfaces. This water-collection method “is a huge advantage for the animal” in its hot, dry habitat, says Esser.