A cud-chewing, even-toed, hoofed mammal. Examples include
cattle, sheep, goat, antelope, giraffe, deer, okapi, and chevrotain. All
except the chevrotain have four-chambered stomachs.
|Impalas are found in the grassland regions of central
and east Africa. Like other ruminants, they can regurgitate food in
small amounts once it has been partly digested, for chewing again,
re-swallowing, and further digestion. This enables them to obtain a
lot of food in small amounts once it has been partly digested, for
chewing again, re-swallowing, and further digestion. This enables them
to obtain a lot of food in a short time, then retreat to a safe, sheltered
place to digest it. When grazing, an impala grasps vegetation between
its spade-like incisors (1) and a hard upper pad (2) and pulls it
up rather then biting it off. The molars (3) are ideal for chewing.
The gap between incisors and molars (4) allows the tongue to mix food
with saliva. The powerful masseter muscle (5) moves the jaw up and
down, while other facial muscles move it side to side for grinding.
Ruminants regurgitate and re-chew their food once having swallowed it. They
feed by filling one compartment of a three- or four-chambered stomach with
unmasticated food, and bringing it back up to the mouth again to be fully
chewed and finally swallowed. This method of feeding is an adaptation in
many herbivores to increase the time available
for digestion of relatively indigestible vegetable matter.