Graphics Reference
In-Depth Information
Anatomy
A huge variety of animals are classified as quadrupeds. Here we'll examine
some of the most common quadruped forms in an attempt to provide a
wide base for study. We covered the general issues of bones, muscles, and
tendons in the previous section, so we concentrate here on the distinctive
skeletal structures, movements, and other topics related to selected animals.
Unlike humans, quadrupeds, when in an upright position, usually have a spine
that is oriented along a more or less horizontal plane, which means that the
angles between spine, neck, and skull are more pronounced than for animals
that move with a more upright gait.
Quadrupeds may be divided into further classifications of
cursorial animals
and
noncursorial animals
. These terms denote the distinctive way in which the
legs of the animals in each classification are oriented.
Cursorial
is a biological
term that describes animals that are adapted to running. It is also a term that is
sometimes linked to animals' feeding habits; a zebra would therefore be classed
as a cursorial grazer, whereas a lion would be classed as a cursorial predator.
FIG 4.10
Cursorial quadrupeds stand
on upright legs with their weight
supported directly over them.
