A comparison of social conditions in the adjoining provinces of Baltistan and Ladak, which together comprise the Himalayan valley of the Indus, reveals the character of polyandry as a response to geographic environment.  Both provinces are inhabited by a Mongolian stock, but the Ladaki living on the uppermost stretch of the basin near Tibet are Buddhists and polyandrists, while the Baltis farther down the valley are Mussulmen and polygamists.  The Baltis, with their plurality of wives and numerous children, are wretchedly poor and live in squalor on the verge of starvation; but as the elevation of their valley ranges only from 4000 to 8500 feet, they are inured to heat, and therefore emigrate in large numbers to the neighboring Mohammedan province of the Punjab, where they work as coolies and navvies.  The Ladakis, on the other hand, living 9000 to 13,000 feet above the sea, die of bilious fever when they reach the lowlands.  Cut off from emigration, they curtail population by means of polyandry and lamaseries.  Consequently they show signs of prosperity, are well fed, well clothed and comfortably housed.[1360] Baltistan’s social condition illustrates in a striking way the power of an idea like an alien creed, assimilated as the result of close vicinal location, to counteract for a time the influences of local geographic conditions.

[Sidenote:  Marauding tendencies in mountaineers]

The less civilized mountain peoples, whose tastes or low economic status unfit them for emigration, solve the problem of a deficient food supply by raiding the fields and stores of their richer neighbors.  Predatory expeditions fill the history of primitive mountain peoples, and of the ancient occupants of highland regions which are now devoted to honest industry.  The ancient Alpine tribes were one and all, from the Mediterranean to the Danube, “poor and addicted to robbery,” as Strabo says.  He analyzes their condition with nice discrimination.  “The greater part [of the Alps], especially the summits of the mountains inhabited by robbers, are barren and unfruitful, both on account of the frost and the ruggedness of the land.  Because of the want of food and other necessaries, the mountaineers have sometimes been obliged to spare the inhabitants of the plains, that they might have some people to supply them."[1361] The freebooters usually descended into the lowlands of Italy, Gaul and Helvetia, but the pass peoples lay in wait for their prey on the mountain roads.  Strabo described the same marauding habits arising from the same cause among the mountaineers of northern Spain,[1362] the Balkan range,[1363] and the highlands encircling the Mesopotamian plains.[1364]