split between Iranian and Old Indic 1800 BCE A key insight is that early expansions of the area in which Indo-European was spoken were often caused by "recruitment", rather than only by military invasions. With the Yamnaya culture as a nucleus candidate, the original recruitment would be to a way of life in which intensive use of horses allowed herd animals to be pastured in areas of the Ukrainian / South Russian steppe, outside of river valleys. Part Two: The Opening of the Eurasian Steppes Chapter Eight: First Farmers and Herders: The Pontic-Caspian Neolithic According to Anthony, the development of the Proto-Indo-European cultures started with the introduction of cattle at the Pontic-Caspian steppes, which, until ca. 5200–5000 BCE, were populated by hunter-gatherers. The first cattle herders arrived from the Danube Valley at ca. 5800–5700 BCE, descendants from the first European farmers. They formed the Criş culture (5800–5300 BCE), creating a cultural frontier at the Prut-Dniestr watershed. The adjacent Bug-Dniester culture (6300–5500 BCE) was a local forager culture from which cattle-breeding spread to the steppe peoples. The Dniepr Rapids area was the next part of the Pontic-Caspian steppes to shift to cattle-herding. It was the most densely-populated area of the Pontic-Caspian steppes at the time and had been inhabited by various hunter-gatherer populations since the end of the Ice Age. From ca. 5800–5200, it was inhabited by the first phase of the Dnieper-Donets culture, a hunter-gatherer culture contemporaneous with the Bug-Dniestr culture. Chapter Nine: Cows, Copper and Chiefs At ca. 5200–5000 BCE, the non-Indo-European Cucuteni-Tripolye culture (5200–3500 BCE) appears east of the Carpathian mountains, moving the cultural frontier to the Southern Bug valley, and the foragers at the Dniepr Rapids shifted to cattle herding, marking the shift to Dniepr-Donets II (5200/5000-4400-4200 BCE). The Dniepr-Donets culture kept cattle not only for ritual sacrifices but also for their daily diet. The Khvalynsk culture (4700–3800 BCE), located at the middle Volga, which was connected with the Danube Valley by trade networks, also had cattle and sheep, but they were "more important in ritual sacrifices than in the diet." According to Anthony, "the set of cults that spread with the first domesticated animals was at the root of the Proto-Indo-European conception of the universe" in which cattle had an essential role. The Samara culture (early 5th millennium BCE), north of the Khvalynsk culture, interacted with the same. The steppe cultures were markedly different, economically and