WHEN A PET DOG BARKS at a stranger or
walks around in a circle before settling down to
sleep, it is behaving in the same way that its gray
wolf ancestors did thousands of years ago. The
dog family is made up of about 36 different
species, including the domestic dog. There are
more than 400 breeds of domestic dog, from
Labrador retrievers to Yorkshire terriers.
Other types of dogs include the Asian
dhole, the African wild dog, many kinds of
foxes, and three species of jackals. These fast-
running hunters are built for chasing prey; their
elongated muzzles allow a large area for housing
sensory organs associated with smell. Some wild dogs,
such as wolves, live in extended family groups called
packs. Each pack has a leader or leaders, to whom all
the other animals in the pack submit. A domestic
dog sees its owner as a pack leader
and is willing to obey that
person’s commands.Reasonable
eyesight in
daylight; night
vision is weak.Carnassials cut through
hide, bone, and flesh.Long, strong legs
for fast, sustained
running
GERMAN SHEPHERD
This dog has a long
muzzle and large ears,
and still resembles its
wolf ancestors. It is a
strong, agile, extremely
intelligent breed of
dog—popular both
as a working dog
and as a pet.
Extremely
sensitive nose
for tracking
animals and
peopleGood hearing, with
ears that turn
to locate the
source of
a soundDogs have four claws
on each paw. The tough
toe pads help them
grip when they run.DOMESTIC DOGS
Dogs have lived in harmony with
humans for more than 30,000 years.
It is probable that over thousands
of years, early humans caught and
tamed several members of the dog
family, at first to help with hunting,
herding, and guarding, and, much
later, to keep as pets. Today, 215
breeds of domestic dogs are
recognized in Britain, and more
than 180 in the United States.
WORKING DOGS
Dogs are trained to do many
jobs for humans. Some tasks,
such as herding sheep or
guarding property, involve the
dog’s natural instincts. Other
jobs include guiding the blind,
pulling sleds, and racing. Many
dogs are trained by the police
and the military to find people
who are trapped or in hiding.GRAY WOLF
This wolf is the
ancestor of our
domestic dogs. It is the
largest member of the
dog family, measuring
up to 6 ft (1.8 m) in
length, including its
tail. Where food is
readily available,
wolves may form a
pack consisting of up
to 36 wolves. They
hunt in packs in winter
but split into smaller
groups in summer.Fur coat keeps
animal warm
and dry.Tail is used to give social signals,
such as wagging when happy.EARLY DOGS
The domestic dog is one
of the 36 species of the dog
family. As this early cave
painting shows, it existed
as long ago as the Stone Age.