Volume 47, Number 1 & 2, Spring/Summer 2019 Archaeology, Genetics, and Language in the Steppes: A Comment on Bomhard David W. Anthony Hartwick College Bomhard’s hypothesis is that PIE was the result of interference between a substrate related to Northwest Caucasian and a dominant language related to Uralic (pre-Uralic?) that absorbed Caucasus-like elements in phonology, morphology, and lexicon. That kind of interference would imply a long period of widespread bilingualism among the pre-Uralic speakers. The shared lexical cognates that Bomhard lists include kinship terms such as ‘daughter-in-law’, suggesting the occurrence of at least occasional formal intermarriage between the two language communities. I have been asked to outline how this hypothesis might correlate with genetic and archaeological evidence ‘on the ground’ in the Pontic-Caspian-North Caucasus region. Much of my assessment is based on research that has been posted on the public server bioarxiv but is not yet formally published. I accept Mallory’s reading of the current consensus that the Yamnaya expansion, beginning about 3000 BC into both Europe and Asia from the Pontic-Caspian steppes, represented the expansion of late PIE languages (after the separation of Anatolian). Putting aside the questions of how and why that expansion occurred, my topic is the formation and origin of the Yamnaya mating network, as a genetic phenomenon; and secondarily of the Yamnaya culture, beginning about 3300 BC within the Pontic-Caspian steppes, as an archaeological phenomenon. I also assess how pre-Yamnaya genetic and archaeological patterns of interaction might correlate with Bomhard’s hypothesis for early PIE origins. Mating networks and IE origins I should note two important facts about ancient DNA (aDNA) studies. First is that large-scale studies involving hundreds of prehistoric individuals analyzed at the whole-genome scale only became methodologically feasible recently, and the first results were published only in 2015 (Haak et al. 2015; Allentoft et al. 2015). So the evidentiary basis under our feet is recently formed