title: Global population divergence and admixture of the brown rat (Rattus norvegicus).
abstract: Native to China and Mongolia, the brown rat (Rattus norvegicus) now enjoys a worldwide distribution. While black rats and the house mouse tracked the regional development of human agricultural settlements, brown rats did not appear in Europe until the 1500s, suggesting their range expansion was a response to relatively recent increases in global trade. We inferred the global phylogeography of brown rats using 32 k SNPs, and detected 13 evolutionary clusters within five expansion routes. One cluster arose following a southward expansion into Southeast Asia. Three additional clusters arose from two independent eastward expansions: one expansion from Russia to the Aleutian Archipelago, and a second to western North America. Westward expansion resulted in the colonization of Europe from which subsequent rapid colonization of Africa, the Americas and Australasia occurred, and multiple evolutionary clusters were detected. An astonishing degree of fine-grained clustering between and within sampling sites underscored the extent to which urban heterogeneity shaped genetic structure of commensal rodents. Surprisingly, few individuals were recent migrants, suggesting that recruitment into established populations is limited. Understanding the global population structure of R. norvegicus offers novel perspectives on the forces driving the spread of zoonotic disease, and aids in development of rat eradication programmes.
authors: Louis Calder Center, Biological Field Station, Fordham University, Armonk, NY 10504, USA emily.e.puckett@gmail.com.
authors: Emily E
authors: 0000-0002-9325-4629
authors: EE
authors: Puckett
authors: Louis Calder Center, Biological Field Station, Fordham University, Armonk, NY 10504, USA.
authors: Jane
authors: J
authors: Park
authors: Louis Calder Center, Biological Field Station, Fordham University, Armonk, NY 10504, USA.
authors: Matthew
authors: M
authors: Combs
authors: Xavier Center for Bioenvironmental Research, Tulane University, New Orleans, LA 70112, USA.
authors: Michael J
authors: MJ
authors: Blum
authors: Clinical Research Unit, Oxford University, Hanoi, Vietnam.
authors: Juliet E
authors: JE
authors: Bryant
authors: Department of Ecology and Evolutionary Biology, Yale University, PO Box 208106, New Haven, CT 06520-8106, USA.
authors: Adalgisa
authors: A
authors: Caccone
authors: Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil.
authors: Federico
authors: F
authors: Costa
authors: Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK.|Mathematical and Statistical Methods Group, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors: Eva E
authors: EE
authors: Deinum
authors: Federal Research Centre for Cultivated Plants, Institute for Plant Protection in Horticulture and Forests, Vertebrate Research, Julius Kühn Institute, Münster, Germany.
authors: Alexandra
authors: A
authors: Esther
authors: Animal Health Centre, British Columbia Ministry of Agriculture, 1767 Angus Campbell Road, Abbotsford, British Columbia, Canada V3G 2M3.
authors: Chelsea G
authors: CG
authors: Himsworth
authors: Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK.
authors: Peter D
authors: PD
authors: Keightley
authors: Laboratory of Epidemiology and Public Health, Yale University, New Haven, CT, USA.
authors: Albert
authors: A
authors: Ko
authors: Department of Medical Biochemistry and Microbiology, Zoonosis Science Center, Uppsala University, Uppsala, Sweden.
authors: Åke
authors: Å
authors: Lundkvist
authors: Wildlife Zoonoses and Vector Borne Disease Research Group, Animal and Plant Health Agency (APHA), Woodham Lane, New Haw Surrey, UK.
authors: Lorraine M
authors: LM
authors: McElhinney
authors: CNRS-CIRAD, Centre d'Infectiologie Christophe Mérieux du Laos, Vientiane, Lao PDR.
authors: Serge
authors: S
authors: Morand
authors: Department of Anthropology, University of Auckland, Private Bag 92019, Auckland, New Zealand.|School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors: Judith
authors: J
authors: Robins
authors: School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.|Department of Statistics, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors: James
authors: J
authors: Russell
authors: Department of Medical Biochemistry and Microbiology, Zoonosis Science Center, Uppsala University, Uppsala, Sweden.
authors: Tanja M
authors: TM
authors: Strand
authors: Laboratorio de Ecologia de Roedores Urbanos, IEGEBA-CONICET, EGE-Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Pabellon II, Ciudad Universitaria (C1428EHA), Buenos Aires, Argentina.
authors: Olga
authors: O
authors: Suarez
authors: School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
authors: Lisa
authors: L
authors: Yon
authors: Louis Calder Center, Biological Field Station, Fordham University, Armonk, NY 10504, USA jmunshisouth@fordham.edu.
authors: Jason
authors: 0000-0002-8067-4341
authors: J
authors: Munshi-South
mesh_terms: D000349:Africa; D000818:Animals; D044362:Australasia; D002681:China; D005060:Europe; D019143:Evolution, Molecular; D005828:Genetics, Population; D006801:Humans; D008986:Mongolia; D009656:North America; D020641:Polymorphism, Single Nucleotide; D051381:Rats / Q000235:genetics*; D012426:Russia
keywords: RAD-Seq; cityscapes; commensal; invasive species; phylogeography; population genomics