This book -in French- addresses the spatial features of nomadic pastoralism among the Mongol herders of Mongolia and Southern Siberia from a cross-comparative perspective. Building upon long-term anthropological fieldwork of more than 20 months, cumulated between 2008 and 2016, this book offers a rare diachronic insight, highlighting the environmental and social changes over many years and the adaptive strategies implemented by the herders. The overall approach is doubly dynamic: taking into account the very interactions of bio-climatic factors, animal behaviour and human decisions, and their feedback loops. The author provides a better understanding of the mutual adaptations of both herders and animals in the common use of unfenced pastures, not only between different herders but also between different species. This was made possible through a slightly de-anthropocentrised approach, giving full agency to the animals. The innovative methodology supports this approach by tracking the animals’ movements through the use of GPS devices, and by aligning these data with geographical information such as rivers, roads, mountains, roads, cultivated fields, etc. Although the theoretical and methodological approach make this book attractive to a wide audience, beyond the specialists of Mongolia and Siberia, special attention has also been given to the graphic representation of data into numerous and original maps. Each one will have been re-designed, specifically for this book, by the Dutch graphic designer Joost Grootens, renowned for his talent in artistically representing complex data.