In Western Europe, indeed, where they have been so much persecuted, most of the beavers live alone in holes, though communities are still left in parts of Germany, Scandinavia, and Siberia. But in North America they still carry on their true communal life, and those who visit their wonderful settlements will not be surprised to learn that they possess the largest brain for their size of any of the gnawing animals. Indeed, they would have no rival among rodents if it were not for the clever sagacious rats, and these have probably sharpened their wits by living so long in contact with man, for they are burrowers chiefly in human dwellings, granaries, stables, mines, ships, and every available dwelling-place where they can rob and plunder, and outwit even man himself by working their way into his stores, and acting together in carrying away his goods. So the insect-eaters and rodents hold their own both by land and water, penetrating, in the forms of bats and mice even to Australia, though the rodents are most widely spread, for except two very rare animals[145] in the West Indian Islands, there are no Insectivora except bats in South America. The bats, however, remind us that both these groups have also found homes above the ground and in the trees. There the _rodents_ have the lovely little Squirrels, which, with their brown red backs, white waistcoats, and graceful bushy tails, scamper up the trees of our English woods. It is very tempting to dwell upon the squirrel, with his little wife, to whom he remains faithful all his life, his beautiful round nest, in which his young are so carefully reared, and his pretty ways as he sits upright gnawing beechnuts or acorns, holding them in his tiny hands. He has made good use of his opportunities, being almost as widely spread as the rat, for there are squirrels of some kind all over the world, wherever there are forests, except in Australia. Several of them in the East and North America have folds of skin at the side of the body, which, when tightly stretched, by extending the four limbs, enable them to take flying leaps from tree to tree (see Fig. 60). Even without flying, however, the squirrel is so nimble that he manages well to escape his enemies, except some of the birds of prey and the fierce tree-marten and wild cat; and as in cold countries he sleeps soundly in snug holes of a tree till the leaves grow again to give him shelter, he is not often detected even by these. [Illustration: Fig. 60. On the tree, the Taguan[146] or flying squirrel, a rodent; Flying below, the Colugo,[147] an insectivorous animal.]