nd unrelated parents?

Half a century ago it was believed that all the evidence which could
be brought to bear upon the problem pointed to an independent origin
of the dog. Youatt, writing in 1845, argued that "this power of
tracing back the dog to the very earliest periods of history, and
the fact that he then seemed to be as sagacious, as faithful, and
as valuable as at the present day, strongly favours the opinion that
he was descended from no inferior and comparatively worthless animal;
and that he was not the progeny of the wolf, the jackal, or the fox,
but was originally created, somewhat as we now find him, the associate
and friend of man."

When Youatt wrote, most people believed that the world was only six
thousand years old, and that species were originally created and
absolutely unchangeable. Lyell's discoveries in geology, however,
overthrew the argument of the earth's chronology and of the antiquity
of man, and Darwin's theory of evolution entirely transformed the
accepted beliefs concerning the origin of species and the supposed
invariability of animal types.

The general superficial resemblance between the fox and many of our
dogs, might well excuse the belief in a relationship. Gamekeepers
are often very positive that a cross can be obtained between a dog
fox and a terrier bitch; but cases in which this connection is alleged
must be accepted with extreme caution. The late Mr. A. D. Bartlett,
who was for years the superintendent of the Zoological Gardens in
London, studied this question with minute care, and as a result of
experiments and observations he positively affirmed that he had never
met with one well-authenticated instance of a hybrid dog and fox.
Mr. Bartlett's conclusions are incontestable. However much in
appearance the supposed dog-fox may resemble the fox, there are
certain opposing characteristics and structural differences which
entirely dismiss the theory of relationship.

One thing is certain, that foxes do not breed in confinement, except
in very rare instances. The silver fox of North America is the only
species recorded to have bred in the Zoological Gardens of London;
the European fox has never been known to breed in captivity. Then,
again, the fox is not a sociable animal. We never hear of foxes
uniting in a pack, as do the wolves, the jackals, and the wild dogs.
Apart from other considerations, a fox may be distinguished from a
dog, without being seen or touched, by its smell.