THE LIFE OF MAMMALS 
to Tunis, keeping within sight of the desert; and Buxton,” who has told 
us much that was novel in regard to the animals of the Sahara and Atlas 
regions, speaks feelingly of their remarkable skill in hiding among the fan- 
tastically worn and brushy rocks of those mountains. All mountain sheep 
and goats know how to stand absolutely motionless and unnoticeable, or 
to lie quietly beside a rock with which their dun hue perfectly blends. 
One or more of a band is likely to choose some high place commanding a 
wide outlook, and so is prepared to catch sight of anything alarming in 
the neighborhood; but the ‘posting of sentinels,” so frequently stated of 
these animals, probably amounts to no more than this habitual watchful- 
ness by wakeful ones. 
Goats differ from the sheep in such small particulars as the 
absence of hoof glands, the rank odor and beard of the rams, 
and in the shape of the horns, which typically are 
high, sweeping, and triangular, and are likely to be 
knobbed on the front. Standing about as high as the average 
wild sheep, say three feet at the shoulder, the goats are rather 
lighter in weight, more active climbers, and are likely to be found 
in more precipitous parts of the mountain system to which they, 
like the sheep, are confined, for no true goat now occurs naturally 
outside of Europe and Asia, except along the Egyptian shore 
of the Red Sea. Geologically, they have been traced back to 
the Pliocene, when an ibex wandered over the chilly plains of 
central Europe; but since the Glacial period they have remained 
upon alpine heights, separating into various closely related 
species by the influence of isolation. Goats are further peculiar 
in being mostly browsers, cropping the leaves and twigs of 
brush, sprouts, and aromatic plants; hence flocks of tame goats 
not only keep the woods where they run free from undergrowth, 
but ruin any attempt to reforest areas once cut over. 
Nearest to the sheep, and with the bharal and aoudad uniting 
the two groups, are the brownish turs of the Cau- 
casus, whose massive black horns are comparatively 
smooth and cylindrical, and extend outward and backward like 
those of the bharal. Very similar are the goats of the moun- 
258 
Goats. 
Turs. 
