The global biogeography of microorganisms remains largely unknown, in contrast to the well-studied diversity patterns of macroorganisms. We used arbuscular mycorrhizal (AM) fungus DNA from 1014 plant-root samples collected worldwide to determine the global distribution of these plant symbionts. We found that AM fungal communities reflected local environmental conditions and the spatial distance between sites. However, despite AM fungi apparently possessing limited dispersal ability, we found 93% of taxa on multiple continents and 34% on all six continents surveyed. This contrasts with the high spatial turnover of other fungal taxa and with the endemism displayed by plants at the global scale. We suggest that the biogeography of AM fungi is driven by unexpectedly efficient dispersal, probably via both abiotic and biotic vectors, including humans.

Centre for Mycorrhizal Research The Energy and Resources Institute India Habitat Centre Lodhi Road New Delhi 110 003 India

Institute of Ecology and Earth Sciences University of Tartu Lai 40 Tartu 51005 Estonia

Institute of Ecology and Earth Sciences University of Tartu Lai 40 Tartu 51005 Estonia Institute of Botany Czech Academy of Sciences Dukelska 135 379 01 Trebon Czech Republic

Institute of Ecology and Earth Sciences University of Tartu Lai 40 Tartu 51005 Estonia Netherlands Institute of Ecology Droevendaalsesteeg 10 6708 PB Wageningen Netherlands

Laboratoire Commun de Microbiologie de l'Institut de Recherche pour le Développement Institut Sénégalais de Recherches Agricoles Université Cheikh Anta Diop Département de Biologie Végétale UCAD BP 5005 Dakar Sénégal

Laboratoire des Symbioses Tropicales et Méditerranéennes Unité Mixte de Recherche 113 Laboratoire de Biologie et Physiologie Végétales Faculté des Sciences Exactes et Naturelles Université des Antilles BP 592 97159 Pointe à Pitre Guadeloupe

School of Earth Sciences and Environmental Sustainability Northern Arizona University Flagstaff AZ 86011 5694 USA

TERI Deakin Nano Biotechnology Centre Biotechnology and Management of Bioresources Division TERI India Habitat Centre Lodhi Road New Delhi 110 003 India

Comment In

Science. 2016 Feb 19;351(6275):826. doi: 10.1126/science.aad4228. PubMed

Comment In

Science. 2016 Feb 19;351(6275):826. doi: 10.1126/science.aad5495. PubMed

References provided by Crossref.org

Global patterns in endemicity and vulnerability of soil fungi

Defending Earth's terrestrial microbiome

Agricultural management and pesticide use reduce the functioning of beneficial plant symbionts

Development of a taxon-discriminating molecular marker to trace and quantify a mycorrhizal inoculum in roots and soils of agroecosystems

A meta-analysis of global fungal distribution reveals climate-driven patterns

Geography and habitat predominate over climate influences on arbuscular mycorrhizal fungal communities of mid-European meadows

Global distribution of earthworm diversity

Open-source data reveal how collections-based fungal diversity is sensitive to global change

Little Cross-Feeding of the Mycorrhizal Networks Shared Between C3-Panicum bisulcatum and C4-Panicum maximum Under Different Temperature Regimes

Fungal root symbionts of high-altitude vascular plants in the Himalayas

Plant Communities Rather than Soil Properties Structure Arbuscular Mycorrhizal Fungal Communities along Primary Succession on a Mine Spoil