Waters, JonathanHewitt, GodfreyFraser, Ceridwen2015-12-070169-5347http://hdl.handle.net/1885/17114Density-dependent processes play a key role in the spatial structuring of biodiversity. Specifically, interrelated demographic processes, such as gene surfing, high-density blocking, and competitive exclusion, can generate striking geographic contrasts in the distributions of genes and species. Here, we propose that well-studied evolutionary and ecological biogeographic patterns of postglacial recolonization, progressive island colonization, microbial sectoring, and even the 'Out of Africa' pattern of human expansion, are fundamentally similar, underpinned by a 'founder takes all' density-dependent principle. Additionally, we hypothesize that older historic constraints of density-dependent processes are seen today in the dramatic biogeographic shifts that occur in response to human-mediated extinction events, whereby surviving lineages rapidly expand their ranges to replace extinct sister taxa.Keywords: biodiversity; demography; density dependence; dispersal; extinction; microbial activity; phylogeography; population genetics; taxonomy; allele; animal; animal dispersal; biodiversity; biological model; evolution; founder effect; human; ice cover; kelp; ph Biodiversity; Biogeography; Colonization; Competitive exclusion; Dispersal; Evolution; Phylogeography; Population genetics201310.1016/j.tree.2012.08.0242016-02-24