vocabularies are limited to about 300 words.

Very many species of animals appear to be voiceless; but it is
hazardous to attempt to specify the species. Sometimes under
stress of new emergencies, or great pain, animals that have been
considered voiceless suddenly give tongue. That hundreds of
species of mammals and birds use their voices in promoting
movements for their safety, there is no room to doubt. The only
question is of the methods and the extent of voice used. Birds and
men give expression to their pleasure or joy by singing.

In the jungle and the heavily wooded wilderness, one hears really
little of vocal wild-animal language. Through countless
generations the noisiest animals have been the first ones to be
sought out and killed by their enemies, and only the more silent
species have survived. All the higher animals, as we call the
higher vertebrates, have the ability to exchange thoughts and
convey ideas; and that is language.

At the threshold of this subject we are met by two interesting
facts. Excepting the song-birds, the wild creatures of today have
learned through instinct and accumulated experience that silence
promotes peace and long life. The bull moose who bawls through a
mile of forest, and the bull elk who bugles not wisely but too
well, soon find their heads hanging in some sportsman's dining-
room, while the silent Virginia deer, like the brook, goes on
forever.

Association with man through countless generations has taught
domestic animals not only the fact of their safety when giving