The snake group, Serpentes, is placed with
lizards in the major reptile group Squamata.
The fossil history of snakes is far shorter
than that for lizards, stretching back to' the .
Late Cretaceous Period about 80 million
years ago. The group origins are obscure:
two suggestions include evolution from
some type of burrowing lizard, hence the
loss of limbs; or evolution from a form of
aquatic lizard. The snake skull is usually
low and squat, with a flattened forehead
and loose ja:w articulation (joint). This .
allows a very wide gape and 'dislocation'
of the jaws to permit swallowing large prey
whole, since the teeth are slim and fang-like
and cannot bite off lumps or chew.
The snake group, Serpentes, is placed with lizards in the major reptile group Squamata. The fossil history of snakes is far shorter than that for lizards, stretching back to' the . Late Cretaceous Period about 80 million years ago. The group origins are obscure: two suggestions include evolution from some type of burrowing lizard, hence the loss of limbs; or evolution from a form of aquatic lizard. The snake skull is usually low and squat, with a flattened forehead and loose ja:w articulation (joint). This . allows a very wide gape and 'dislocation' of the jaws to permit swallowing large prey whole, since the teeth are slim and fang-like and cannot bite off lumps or chew.
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