Language trees with sampled ancestors support a hybrid model for the origin of Indo-European languages

The origins of the Indo-European language family are hotly disputed. Bayesian phylogenetic analyses of core vocabulary have produced conflicting results, with some supporting a farming expansion out of Anatolia ~9000 years before present (yr B.P.), while others support a spread with horse-based pastoralism out of the Pontic-Caspian Steppe ~6000 yr B.P. Here we present an extensive database of Indo-European core vocabulary that eliminates past inconsistencies in cognate coding. Ancestry-enabled phylogenetic analysis of this dataset indicates that few ancient languages are direct ancestors of modern clades and produces a root age of ~8120 yr B.P. for the family. Although this date is not consistent with the Steppe hypothesis, it does not rule out an initial homeland south of the Caucasus, with a subsequent branch northward onto the steppe and then across Europe. We reconcile this hybrid hypothesis with recently published ancient DNA evidence from the steppe and the northern Fertile Crescent.

The policy context for community development practice in public health: a Canadian case study

The Community Action in Public Health Study explored how public health managers, frontline staff, and community participants interpret, implement and receive policy guidelines urging collaboration with community groups in public health work. In-depth case studies of 6 public health units in Ontario, Canada focussed on 19 community development projects in 3 program areas (107 interviews). In the absence of formal policy guidelines on community development at provincial or local levels, informal policy predominated. Local senior management frequently set the tone, distinguishing health units in which community development was a basic philosophy underlying a broad spectrum of public health practice from those in which it was seen as only one among many possible strategies. Uncertainty and risk associated with informal policy lead many frontline staff to adopt strategies intended to preserve autonomy in community work, including "seeking forgiveness rather than permission" and maintaining relative "invisibility."

The challenge of genuine power sharing in participatory research: the gap between theory and practice

Participatory research is often suggested as a strategy to overcome power imbalances between researchers and research "subjects" because it values equally the knowledge of each individual who participates in the project. However, there is little documentation of the dilemmas that may arise when a complex community service organization attempts to engage in participatory research. In our experience of a participatory research project with multiple partners, power imbalances arose from organizationally based perspectives that were unaccounted for in the participatory research literature, demonstrating that power is a complex and elusive factor in establishing equal relations.