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Summary1. Landscape genetics studies using neutral markers have focused on the relationship between gene flow and landscape features. Spatial patterns in the genetic distances among individuals may reflect spatially uneven patterns of gene flow caused by landscape features that influence movement and dispersal. 2. We present a method and software for identifying spatial neighbourhoods in genetic distance data that adopts a regression framework where the predictors are generated using Moran's eigenvectors maps (MEM), a multivariate technique developed for spatial ecological analyses and recommended for genetic applications. 3. Using simulated genetic data, we show that our MEMGENE method can recover patterns reflecting the landscape features that influenced gene flow. We also apply MEMGENE to genetic data from a highly vagile ungulate population and demonstrate spatial genetic neighbourhoods aligned with a river likely to reduce, but not eliminate, gene flow. 4. We developed the MEMGENE package for R in order to detect and visualize relatively weak or cryptic spatial genetic patterns and aid researchers in generating hypotheses about the ecological processes that may underlie these patterns. MEMGENE provides a flexible set of R functions that can be used to modify the analysis. Detailed supplementary documentation and tutorials are provided.

Understanding the evolutionary history of contemporary animal groups is essential for conservation and management of endangered species like caribou (Rangifer tarandus). In central Canada, the ranges of two caribou subspecies (barren-ground/woodland caribou) and two woodland caribou ecotypes (boreal/eastern migratory) overlap. Our objectives were to reconstruct the evolutionary history of the eastern migratory ecotype and to assess the potential role of introgression in ecotype evolution. STRUCTURE analyses identified five higher order groups (i.e. three boreal caribou populations, eastern migratory ecotype and barren-ground). The evolutionary history of the eastern migratory ecotype was best explained by an early genetic introgression from barren-ground into a woodland caribou lineage during the Late Pleistocene and subsequent divergence of the eastern migratory ecotype during the Holocene. These results are consistent with the retreat of the Laurentide ice sheet and the colonization of the Hudson Bay coastal areas subsequent to the establishment of forest tundra vegetation approximately 7000 years ago. This historical reconstruction of the eastern migratory ecotype further supports its current classification as a conservation unit, specifically a Designatable Unit, under Canada’s Species at Risk Act. These findings have implications for other sub-specific contact zones for caribou and other North American species in conservation unit delineation.

. 2016. Łeghaǵots'enetę (learning together): the importance of indigenous perspectives in the identification of biological variation. Ecology and Society 21 (2) ABSTRACT. Using multiple knowledge sources to interpret patterns of biodiversity can generate the comprehensive species characterizations that are required for effective conservation strategies. Caribou (Rangifer tarandus) display substantial intraspecific variation across their distribution and in the Sahtú Region of the Northwest Territories, Canada, three caribou types, each with a different conservation status, co-occur. Caribou are essential to the economies, culture, and livelihoods of northern indigenous peoples. Indigenous communities across the north are insisting that caribou research be community-driven and collaborative. In response to questions that arose through dialogue with five Sahtú Dene and Métis communities, we jointly developed a research approach to understand caribou differentiation and population structure. Our goal was to examine caribou variation through analysis of population genetics and an exploration of the relationships Dene and Métis people establish with animals within bioculturally diverse systems. To cultivate a research environment that supported łeghaǵots'enetę "learning together" we collaborated with Ɂehdzo Got'ınę (Renewable Resources Councils), elders, and an advisory group. Dene knowledge and categorization systems include a comprehensive understanding of the origin, behaviors, dynamic interactions, and spatial structure of caribou. Dene people classify todzı "boreal woodland caribou" based on unique behaviors, habitat preferences, and morphology that differ from ɂekwę "barren-ground" or shuhta ɂepę "mountain" caribou. Similarly, genetic analysis of material (microsatellites and mitochondrial DNA) from caribou fecal pellets, collected in collaboration with community members during the winter, provided additional evidence for population differentiation that corresponded to the caribou types recognized by Dene people and produced insights into the evolutionary histories that contribute to the various forms. We developed culturally respectful and relevant descriptions of caribou variation through partnerships that respect the lives and experiences of people that depend on the land. By prioritizing mutual learning, researchers can broaden their understanding of biodiversity and establish a common language for collaboration.

Aim Glacial-interglacial cycles influenced the contemporary genetic structure of many North American species. While phylogeographical lineage divergence among Pleistocene refugia has been proposed as a significant driver of subspecific and ecotypic differentiation, emerging evidence highlights the role of diversification within refugia in producing post-glacial variation. Caribou (Rangifer tarandus) exhibit significant morphological, ecological and behavioural phenotypic variation and occurred within Beringian and sub-Laurentide refugia. More specifically, the boreal ecotype of woodland caribou ranges from the southern regions of Canada to the Northwest Territories (NWT). Woodland caribou are generally accepted to have evolved south of the glacial extent, but the boreal ecotype in the northern part of their range co-occurs with caribou that have a Beringian origin. This proximity provides an opportunity to test whether woodland caribou colonized boreal habitats from a single southern refugial source or if independent evolution to a common ecotype resulted from diversification within refugia.Location Northwestern Canada.Methods We used approximate Bayesian computation to discriminate between alternate evolutionary histories of caribou belonging to boreal, northern mountain and barren-ground ecotypes using microsatellite and mtDNA markers.Results Our analysis indicates that unlike the southern-evolved boreal ecotype, the boreal ecotype of central NWT has Beringian origins and arose from a common lineage with barren-ground and mountain caribou. Importantly, the divergence of the lineage resulting in the boreal ecotype of central NWT significantly pre-dates the Last Glacial Maximum.Main conclusions We demonstrate that independent evolutionary trajectories can converge on a similar phenotype and for the first time show that the boreal ecotype of caribou in North America contains two phylogeographical assemblages. The ancient divergence suggests that diversification within Beringia could have resulted in ecological specialization. An eco-evolutionary focus will be essential to designing biodiversity conservation strategies for caribou that maximize genetic diversity and preserve adaptive potential in this intraspecifically diverse species.