Post-Pleistocene radiation of the pea aphid complex revealed by rapidly evolving endosymbionts

• DOI: 10.1073/pnas.0905129106
• Publication Date: 2009-09-05T02:18:19Z
• Authors: Jean Peccoud; Jean-Christophe S...; Heather J. McLaug...; Nancy A. Moran
• Keywords: DNA, Bacterial; 0301 basic medicine; Time Factors; ECOLOGICAL SPECIATION; Models, Genetic; 590; Genetic Variation; [SDV.BC]Life Sciences [q-bio]/Cellular Biology; ADAPTIVE RADIATION; Evolution, Molecular; 03 medical and health sciences; NEOLITHIC AGRICULTURE; Buchnera; Aphids; Host-Pathogen Interactions; HOST RACES; Animals; ACYRTHOSIPHON PUSUM; Symbiosis; [SDV.BC] Life Sciences [q-bio]/Cellular Biology; Pisum sativum; Phylogeny

Adaptation to different resources has the potential cause rapid species diversification, but few studies have been able quantify time scale of recent adaptive radiations. The pea aphid, Acyrthosiphon pisum , a model speciation for host-specialized parasites, consists several biotypes (races or species) living on distinct legume hosts. To document this radiation, we used rapidly evolving sequences from Buchnera maternally transmitted bacterial endosymbiont aphids. Analyses pseudogene revealed that 11 host-associated sort mostly into matrilines despite low sequence divergence. A calibration based divergence times 7 sequenced genomes allowed us date last maternal ancestor these between 8,000 and 16,000 years, with burst diversification at an estimated 3,600–9,500 years. recency which is supported by microsatellite data, implies aphid complex ranks among most radiations yet documented. This coincides post-Pleistocene warming domestication anthropogenic range expansion hosts Thus, hypothesize new availability abundance triggered cascade events in newly formed complex.