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This portion of a cave painting in
Lascaux, France, was done by Paleolithic artists in
about 13,000 BC. Prehistoric humans may have believed
that by painting cows, horses, and other animals, they
could gain magical powers that would ensure a
successful hunt. |
Throughout
human history, mammals have played an important part in
providing food and useful materials. At first, humans exploited
them solely by hunting, but by about 14,000 years ago, humans
started to domesticate certain species, controlling the way that
they lived and bred. The earliest domesticated mammal was almost
certainly the dog, which is descended from wolves. Domestication
probably began when hunters adopted wolf cubs, and then used
them as allies for scenting out game. Cats are thought to have
been domesticated about 4500 years ago, and are descended from
the African wild cat, an animal revered by the ancient Egyptians
and widely valued for dealing with rodent pests.
Human hunters
also discovered that herding mammals could be controlled. At
first, they simply drove animals into places where natural
boundaries such as cliffs and shorelines made them easier to
attack, but over time, subtler techniques developed. People
learned how to follow herds and manage them, first by traveling
with them, and later by confining them in limited areas.
Controlled breeding then produced distinct breeds, each with its
own combination of useful characteristics. Horses, for example,
were initially hunted for food, but later became valued as a
means of transportation. Cattle were bred for meat, milk, and
hides, while goats and sheep were raised for food and also for
their wool.
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Most authorities agree that the
domestic cat descended from the Caffre cat, a small
breed of African wildcat. The Caffre cat was
domesticated in ancient Egypt, possibly as early as
2500 BC. |
Among the few
nonhoofed mammals to have been domesticated—aside from dogs
and cats—are the European rabbit and cavy, or South American
guinea pig, both of which provide meat, and the ferret.
Descended from the European polecat, the ferret is sometimes
kept as a pet, but was originally raised to drive rabbits from
their burrows so they could be caught in hunters' nets.
Domesticated
mammals now supply a large proportion of the meat humans eat and
the fibers used for making clothes, although some wild animals
are still hunted for food and for their fur. Until recently,
mammals also supplied two other commodities—ivory and animal
oils. Ivory is the hard white substance that makes up the tusks
of elephants, and some other large mammals such as walruses.
Long prized for carving and for use in luxury goods, its sale is
now strictly controlled worldwide in an effort to protect
elephant populations. Valuable animal oil is found in marine
mammals, particularly the sperm whale. At the beginning of the
20th century it was an important industrial raw material and a
fuel for domestic lighting, but with the current worldwide
moratorium on whaling, this form of oil is no longer marketed.
Many kinds of
mammals are kept as pets, but some species are kept in captivity
for other reasons. In scientific research, mice and rats act as
living testing laboratories for new drugs, and for new methods
of medical treatment. Primates are also used extensively in
medical research, because they are closely related to humans.
Most of this work is carried out on animals born and raised in
captivity, but in spite of its value, it remains controversial.
In future years it is likely that tests involving computer
modeling will replace many experiments currently carried out
with living mammals
In today's
rapidly changing world, many wild mammals face an increasingly
difficult struggle for survival. Data released in 1996 by the
World Conservation Union (also known as IUCN) indicates that of
about 4600 species of mammal known to exist, over 1000 are
classified as being at risk for extinction
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The
quagga is a zebra that has disappeared in 1883 |
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