Emergent sustainability in open property regimes.

Current theoretical models of the commons assert that common-pool resources can only be managed sustainably with clearly defined boundaries around both communities and the resources that they use. In these theoretical models, open access inevitably leads to a tragedy of the commons. However, in many open-access systems, use of common-pool resources seems to be sustainable over the long term (i.e., current resource use does not threaten use of common-pool resources for future generations). Here, we outline the conditions that support sustainable resource use in open property regimes. We use the conceptual framework of complex adaptive systems to explain how processes within and couplings between human and natural systems can lead to the emergence of efficient, equitable, and sustainable resource use. We illustrate these dynamics in eight case studies of different social-ecological systems, including mobile pastoralism, marine and freshwater fisheries, swidden agriculture, and desert foraging. Our theoretical framework identifies eight conditions that are critical for the emergence of sustainable use of common-pool resources in open property regimes. In addition, we explain how changes in boundary conditions may push open property regimes to either common property regimes or a tragedy of the commons. Our theoretical model of emergent sustainability helps us to understand the diversity and dynamics of property regimes across a wide range of social-ecological systems and explains the enigma of open access without a tragedy. We recommend that policy interventions in such self-organizing systems should focus on managing the conditions that are critical for the emergence and persistence of sustainability.

Inheritance and inequality among nomads of South Siberia.

At the headwaters of the Yenisei River in Tuva and northern Mongolia, nomadic pastoralists move between camps in a seasonal rotation that facilitates their animals' access to high-quality grasses and shelter. The use and informal ownership of these camps depending on season helps illustrate evolutionary and ecological principles underlying variation in property relations. Given relatively stable patterns of precipitation and returns to capital improvement, families generally benefit from reusing the same camps year after year. We show that locations with higher economic defensibility and capital investment-winter camps and camps located in mountain/river valleys-are claimed and inherited more frequently than summer camps and camps located in open steppe. Camps are inherited patrilineally and matrilineally at a ratio of 2 : 1. Despite its practical importance, camp inheritance is not associated with livestock wealth today, which is better predicted by education and wealth outside the pastoral economy. The relationship between the livestock wealth of parents and their adult children is significantly positive, but relatively low compared to other pastoralists. The degree of inequality in livestock wealth, however, is very close to that of other pastoralists. This is understandable considering the durability and defensibility of animal wealth and economies of scale common across pastoralists. This article is part of the theme issue 'Evolutionary ecology of inequality'.

Investigating reindeer pastoralism and exploitation of high mountain zones in northern Mongolia through ice patch archaeology.

In interior Eurasia, high mountain zones are crucial to pastoral subsistence, providing seasonally productive pastures and abundant wild resources. In some areas of northern Mongolia, mountainous tundra zones also support a low-latitude population of domestic reindeer herders-a lifestyle whose origins are poorly characterized in the archaeological record of early Mongolia. Traditionally, reindeer pastoralists make significant seasonal use of munkh mus (eternal ice) for their domestic herds, using these features to cool heat-stressed animals and provide respite from insect harassment. In recent years, many of these features have begun to melt entirely for the first time, producing urgent threats to traditional management techniques, the viability of summer pastures, and reindeer health. The melting ice is also exposing fragile organic archaeological materials that had previously been contained in the patch. We present the results of horseback survey of ice patches in Baruun Taiga special protected area, providing the first archaeological insights from the region. Results reveal new evidence of historic tool production and wild resource use for fishing or other activities, and indicate that ice patches are likely to contain one of the few material records of premodern domestic reindeer use in Mongolia and lower Central Asia. The area's ancient ice appears to be rapidly melting due to changing climate and warming summer temperatures, putting both cultural heritage and traditional reindeer herding at extreme risk in the years to come.