Reconstruction of past backyard skating seasons in the Original Six NHL cities from citizen science data

This study conducted linear and change-point analyses of historical trends since 1942 in the length and number of days suitable for skating on backyard rinks in the “Original Six” National Hockey League cities of Boston, Chicago, Detroit, Montreal, New York, and Toronto. Analysis is based on the relationship between ambient air temperatures and the probability of skating, using thresholds identified through the RinkWatch citizen science project. In all cities, coefficient estimates suggest the number of high-probability skating days per winter is declining, with easternmost cities displaying notable declines and growing inter-annual variability in skating days in recent decades. Linear analysis shows a statistically significant decline in Toronto, with a step-change emerging in 1980, after which there is on average one-third fewer skating days compared with preceding decades. The outdoor skating season trends towards later start dates in Boston, Montreal, New York, and Toronto. Future monitoring of outdoor rinks provides an opportunity for engaging the public in identification of winter warming trends that might otherwise be imperceptible, and for raising awareness of the impacts of climate change.     

Forming and Shaping Pottery Boundaries in Contemporary South-Eastern Botswana

In southern African archaeology, the equation of pottery styles with archaeological ‘cultures’ and their attribution to the antecedents of contemporary ethnic groups has been a common practice for a long time. Ethnoarchaeological studies from other parts of Africa and beyond have shown that the matter is complex and that stylistic and technological boundaries in ceramic distributions can reflect different kinds of social boundaries under different circumstances. To expand on these findings and make them locally relevant, a large-scale ethnoarchaeological study of 41 potters in south-eastern Botswana aims for a better understanding of ceramic technological style and boundary relations. Here, we present and explain only the results concerning the boundaries in the forming and shaping stage of ceramic vessel manufacture. We conclude that learning networks explain the visible boundaries in the technological style of forming and shaping pots in south-eastern Botswana today; language and ethnic affiliation do not. Boundaries in the other stages in the operational sequence of pottery manufacture, such as clay sourcing and preparation, vessel surface treatment and decoration, firing and finishing, will be presented in a series of further publications.     

The First Herders at the Cape of Good Hope

It is generally accepted that the earliest livestock and pottery were brought to the southern tip of Africa by Khoi-speaking herders from northern Botswana around 2000 years ago. The archaeological remains of that age, however, show no sign of such a migration. Rather, some evidence points to the arrival of the Khoi in the southwestern Cape toward the end of the first millennium AD. The earliest livestock and pottery, it is argued, probably reached the Cape of Good Hope some 2000 years ago by a process of diffusion. The implications of this model for the current debates on the transition from hunting to herding in southern Africa are discussed.     

Does Diversification Improve Livelihoods? Pastoral Households in Xinjiang,China

Diversification is routinely promoted to improve poor rural peoples’ livelihoods. However, policy recommendations for livelihood diversification based on evidence from crop‐cultivating sedentary rural societies may not work for mobile pastoral communities, where socio‐ecological conditions predetermine livestock herding as the preferred livelihood strategy. Using survey and semi‐structured interview data collected from 159 households in the Altay and Tianshan Mountains of Xinjiang, China, this study applies cluster analysis to identify six distinct groups based on livelihood strategies: pastoralists, agropastoralists, crop farmers, wage labourers, hired herders and mixed smallholders. Although pastoralism is the least diverse of these in terms of sources of income, it is significantly more diverse in ecological dimensions such as spatial movement, land use pattern and livestock portfolio. Patterns of livelihood diversification and their relationship with household incomes indicate that pastoralism, although preferred, is unattainable for 55 per cent of households given their meagre asset endowments and the pressure of government policies toward sedentarization. The results strongly suggest that livelihood diversification does not improve welfare for pastoral households. Future development interventions should promote policies that enable households to regain flexible access to pastures and should aim to correct the imbalance of opportunities that exists in northern Xinjiang.