Almost all the expressive movements now described, with the exception of the grinning from joy, are innate or instinctive, for they are common to all the individuals, young and old, of all the breeds. Most of them are likewise common to the aboriginal parents of the dog, namely the wolf and jackal; and some of them to other species of the same group. Tamed wolves and jackals, when caressed by their masters, jump about for joy, wag their tails, lower their ears, lick their master’s hands, crouch down, and even throw themselves on the ground belly upwards.[504] I have seen a rather fox-like African jackal, from the Gaboon, depress its ears when caressed. Wolves and jackals, when frightened, certainly tuck in their tails; and a tamed jackal has been described as careering round his master in circles and figures of eight, like a dog, with his tail between his legs. It has been stated[505] that foxes, however tame, never display any of the above expressive movements; but this is not strictly accurate. Many years ago I observed in the Zoological Gardens, and recorded the fact at the time, that a very tame English fox, When caressed by the keeper, wagged its tail, depressed its ears, and then threw itself on the ground, belly upwards. The black fox of North America likewise depressed its ears in a slight degree. But I believe that foxes never lick the hands of their masters, and I have been assured that when frightened they never tuck in their tails. If the explanation which I have given of the expression of affection in dogs be admitted, then it would appear that animals which have never been domesticated—namely wolves, jackals, and even foxes—have nevertheless acquired, through the principle of antithesis, certain expressive gestures; for it is not probable that these animals, confined in cages, should have learnt them by imitating dogs.