appear to move swiftly across the ground, but
they actually move slower compared with many
other animals. Garter snakes, pythons, and some
other snakes have been timed at a speed of only 1
mile per hour. The fastest speed on record is
that of an African black mamba, which was timed
at a speed of 7 miles per hour over a short
distance. In comparison, human beings can easily
run short distances at 10 to 15 miles per hour.
Snakes have four main methods
of moving about: (1) lateral undulation, (2)
rectilinear movement, (3) concertina movement,
and (4) sidewinding. Some snakes also move in
other, unusual ways.
Lateral Undulation (also known as
Serpentine) is the most common way in which
snakes move about. The snake flexes its muscles
to produce a series of horizontal waves from head
to tail. The loops of its body push against
rocks, plants, twigs, or rough areas on a
surface. In this manner, the snake's body is
All snakes can swim by
producing the wavelike motions typical of lateral
undulation. But sea snakes have a body shape that
makes them especially good swimmers. The body is
flattened from side to side, and the tail forms
an oarlike paddle.
Rectilinear Movement (also known as
Creeping) is used by many snakes to climb
trees or move through narrow burrows. In
addition, many thick-bodied snakes, such as puff
adders and pythons, may use rectilinear movement
when crawling along on the ground.
In rectilinear movement, the
snake contracts certain muscles that pull its
belly scales forward. The back edges of the
scales catch on bark or rough areas in the soil.
The snake then contracts other muscles, which
pushes the scales against the bark or rough areas
and so moves the body forward.
Rat snakes and many other
climbing snakes have belly scales especially
suited to rectilinear movement. The edges of the
scales are squared, and they easily catch on bark
as the snake creeps up a tree.
Concertina Movement is often
used by snakes to climb through trees or move
over smooth surfaces. The snake moves the front
part of its body forward and coils it slightly,
pressing against the surface to anchor itself.
The snake then pulls its back end forward and
coils it. The back end is pressed down, providing
leverage for the front part to move forward
Sidewinding is used chiefly by
certain snakes that live in areas with loose soil
or sand. These snakes include the sidewinder of
North America and the carpet viper and horned
viper of Africa. In sidewinding, the snake's head
and tail serve as supports. The snake lifts the
trunk of its body off the ground and moves it
sideways. The snake then moves its head and tail
into position with the rest of its body. It then
repeats the sequence.
Unusual Ways of Moving.
Many small species of snakes seem to
"jump" when trying to escape from
danger. They hurl the body forward or to the side
by rapidly straightening up from a coiled
position. Two gliding snakes of southern Asia can
"parachute" from a high limb to a lower
one or from one tree to another. They spread
their rids, which flattens the body and so helps
slow the fall.
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