“The thorny devil, a tiny highly specialised lizard from the
central Australian desert which lives entirely on ants has each
scale enlarged and drawn out to a point in the centre. Few birds
could relish such a thorny mouthful and to that extent, they
must be a very effective defence, but the shape of the scales
also serves another and most unusual function. Each is scored
with very thin grooves radiating from the central peak. During
cold nights, dew condenses on them and is drawn by capillary
action along the grooves and eventually down to the tiny
creature’s mouth.” (Attenborough 1979:164) The Thorny Devil
(Moloch horridus) can gather all the water it needs directly
from rain, standing water, or from soil moisture, against
gravity without using energy or a pumping device. Water is
conveyed to this desert lizard’s mouth by capillary action
through a circulatory system on the surface of its skin,
comprised of semi-enclosed channels 5-150 µm wide running
between cutaneous scales. Channel surfaces are heavily c