Because snakes cannot bite or tear their food to pieces, prey must be swallowed whole. The
body size of a snake has a major influence on its eating habits. The snake’s jaw is one of
the most unique jaws in the animal kingdom. Snakes have a very flexible lower jaw, the two
halves of which are not rigidly attached, and numerous other joints in their skull, allowing
them to open their mouths wide enough to swallow their prey whole.
Some snakes have a venomous bite, which they use to kill their prey before eating it; others
kill their prey by constriction, and still others swallow their prey whole and alive. After
eating, snakes become dormant while the process of digestion takes place. The process is
highly efficient, with the snake’s digestive enzymes dissolving and absorbing everything but
the prey’s hair and claws.
Most snakes use specialized belly scales to travel, gripping surfaces. The body scales may
be smooth, keeled or granular (Figure13.25). Snakes’ eyelids are transparent “spectacle”
scales which remain permanently closed. In the shedding of scales, or molting, the complete
outer layer of skin is shed in one layer (Figure13.26). Molting replaces old and worn skin,
allows the snake to grow and helps it get rid of parasites such as mites and ticks.
Figure 13.25: A close up of snake scales of a banded krait,Bungarus fasciatus, showing Black
and yellow alternating bands and spaces between scales. ( 6 )
Although a wide range of reproductive modes are used by snakes, all snakes employ internal
fertilization, accomplished by means of paired, forked hemipenes, which are stored inverted
in the male’s tail. Most species of snakes lay eggs and most species abandon them shortly
after laying.