title: Founder takes all: density-dependent processes structure biodiversity.
abstract: Density-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.
authors.affiliation: Allan Wilson Centre for Molecular Ecology and Evolution, Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9016, New Zealand. jon.waters@otago.ac.nz
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Waters
authors.forename: Ceridwen I
authors.initials: CI
authors.lastname: Fraser
authors.forename: Godfrey M
authors.initials: GM
authors.lastname: Hewitt
mesh_terms: D000483:Alleles; D063147:Animal Distribution; D000818:Animals; D044822:Biodiversity; D005075:Biological Evolution; D018703:Founder Effect; D006801:Humans; D046448:Ice Cover; D044423:Kelp; D008957:Models, Genetic; D058974:Phylogeography; D011156:Population Density