Page 124 - One Million Things: Animal Life - The Incredible Visual Guide

NEW VARIETIES

In the natural world, species change over time in a process
called evolution. Evolution works through natural selection,
with animals best adapted to a particular habitat more likely
to survive long enough to breed and pass on their features to
new generations than those that are less well adapted.
For thousands of years, humans have used artificial
selection (selective breeding) to produce new varieties of
domesticated (tamed) animals for their own use. Genetic
modification is the latest form of human interference.

African wildcat Pet cat Aurochs

Breeding has
produced a
flattened face

Gray wolf

CATS
When agriculture developed
in the Middle East and Egypt
more than 8,000 years ago,
harvested crops had to be
stored. These stores were
devastated by rodents such
as rats and mice. Farmers
domesticated wild cats to kill
the rodents. Later, selective
breeding produced
the varieties of cat
breeds seen today.

Chihuahua

DOGS
Domesticated From Great Danes to Chihuahuas, all breeds of
cockerel dogs are descended from wolves. Wolves were
the first animals to be domesticated, about
13,000 years ago. Initially they were used for
hunting, but, later, selective breeding was used
to produce a variety of working dogs and pets.
Junglefowl
CHICKENS
The junglefowl found today in the forests
of southeast Asia is the bird from which
domestic chickens originated about 8,000
years ago. People tamed these birds to
obtain both eggs and meat as food, then
122 bred them to create new varieties.

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