One of the most distinctive of all animal fossils is the
skull of the 'giant Permian newt' Diplocaulus.
The skull is immediately recognized from its
boomerang-like shape, with two long,
backswept, pointed 'horns', on either side,
smallish eye sockets (orbits) set
relatively close together near the
front, and two much smaller
nostrils just on top of the blunt
snout. Associated b;ckbones (vertebrae) and limb
bones show that Diplocaulus was probably newt-
like in shape and about Iml31.ft in length. The function
of Diplocaulus's extraordinary head shape is much
debated. One suggestion is that it was a defensive
adaptation - a predator would need a very large mouth
gape to engulf the head. Or the skull may have been
hydrodynamic, working like the wing of an aircraft, but
in water, to provide a lifting force as Diplocaulus swam
with its relatively weak limbs.