Evidence for variation in ancient livestock pasturing strategies in the Kazakh steppe
Differences in carbon and nitrogen isotope values between ancient livestock indicate that horses were grazed extensively, while ruminants were grazed intensively.
An international team, including researchers from Kiel University and the Max Planck Institute for the Science of Human History, have demonstrated that the isotopic composition of contemporary vegetation communities can be used to better understand animal management strategies used in the past.
Using isotopic data from contemporary vegetation collected from the open steppe, the team constructed isotopic landscapes, or isoscapes, to explore variation in the underlying floral biome. Contemporary carbon and nitrogen isoscapes were then referenced to interpret variation in isotope values obtained from ancient livestock.
Today, pastoralists employ diverse pasturing strategies to ensure herds have a source of fresh graze and keep their animals healthy, and this study shows this was the case in the past as well. Differences in carbon and nitrogen stable isotope values between horses and ruminants belonging to ancient pastoralists in what is now northern Kazakhstan strongly suggest that they were grazed extensively and intensively, respectively. Horses were highly mobile and were allowed to freely graze on pastures extending over wide areas, while sheep, goats and cattle were grazed intensively in pastures with isotopically variable plant communities in close proximity to settlements.
“We discovered that horses grazed in open steppe areas or often in well-watered areas, probably staying well outside of settlements. In contrast, cattle, sheep and goats were grazed in different types of pastures, both near settlements and probably further afield” explains Alicia Ventresca Miller of the Max Planck Institute for the Science of Human History. “Our findings also suggest that livestock management practices did not shift with changes in settlement patterns, demonstrating consistency in pastoral adaptations through time in the region.”
“Studies like this highlight how stable isotopes in plant ecology can be connected to archaeological isotopic data sets to inform on animal management strategies used millennia ago,” says Cheryl Makarewicz of the University of Kiel. “Although the precise spatial distribution of carbon and nitrogen isotopes in ancient steppe floral biomes was certainly different from that of today, additional isoscapes could help us gain a finer-grained understanding of how soil nutrient dynamics and water availability may have influenced the isotopic composition of herd animals.”