These long-necked creatures can see far above the usual short thorny bush, and it is exceeding difficult to get near them. Water probably exists under the stony grit soil, but at present one has to be contented with that found in the stagnant pools at Taru, Maungu, etc., which, if not occupied by the decaying remains of a dead antelope, are, as a rule, drinkable.[46] [46] _Naturalist in Mid-Africa._ These acacias are quite well fitted to live in this dry and arid region. Their roots go down to twenty feet or more, so as to reach the deep-seated water supplies. Their leaves are generally adapted to resist any injury from the strong glare of the sunshine. The gums, already alluded to, are also very important, for any crack or break in the tree is promptly gummed up, and there is no loss of precious water thereby. This gum will also prevent or discourage burrowing and boring insects from getting in; they would, if they tried to do so, become "flies in amber," like those found in fossil resin. The trees are generally provided with strong spines, which guard them from the many grazing animals which try to devour the succulent leaflets. The fight between the grazing animal and the plant is, in these scrubs and half-deserts, very severe. In Egypt it is said that the whole flora has been entirely altered by the camel and the donkey.[47] [47] Floyer. But in this case the battle is unfair. Man keeps those camels, donkeys, and goats. He provides them with water and protects them from lions, leopards, and snakes. In East Africa man has not yet interfered, and the plants probably get the better of the animals. In such places lions, leopards, and hyenas are common. It will be remembered that a lion not very long ago stormed and took charge of a railway station on the line to Uganda, and was only routed with very heavy loss. There is also some reason to suppose that the antelopes and other creatures do help the plants in their efforts to colonize the Sahara. Their droppings will very greatly improve the soil, and more vigorous thickets and undergrowth will spring up when the soil is improved in this way. Such a vigorous growth of plants will be better able to resist the long eight or nine months' drought, and so help the wood to develop, until perhaps it is too thick, and the trees are too high, for the antelopes to graze upon them. In this manner the Acacia scrub is slowly and painfully colonizing the desert.