The mitochondrial ancestor of bonobos and the origin of their major haplogroups.

Hiroyuki Takemoto,Serge Darroze,Kumugo Yangozene,John A Hart,Tetsuya Sakamaki,Mbangi N Mulavwa,Amy K Cobden,Yoshi Kawamoto,Emiko Makinose,Nahoko Tokuyama,Céline Devos,Shoko Higuchi,Patrick Guislain,Jef Dupain,Takeshi Furuichi,Térese B Hart,Gay E Reinartz,David Caramelli

doi:10.1371/journal.pone.0174851

Abstract

We report here where the most recent common ancestor (MRCA) of bonobos (Pan paniscus) ranged and how they dispersed throughout their current habitat. Mitochondrial DNA (mtDNA) molecular dating to analyze the time to MRCA (TMRCA) and the major mtDNA haplogroups of wild bonobos were performed using new estimations of divergence time of bonobos from other Pan species to investigate the dispersal routes of bonobos over the forest area of the Congo River’s left bank. The TMRCA of bonobos was estimated to be 0.64 or 0.95 million years ago (Ma). Six major haplogroups had very old origins of 0.38 Ma or older. The reconstruction of the ancestral area revealed the mitochondrial ancestor of the bonobo populations ranged in the eastern area of the current bonobos’ habitat. The haplogroups may have been formed from either the riparian forests along the Congo River or the center of the southern Congo Basin. Fragmentation of the forest refugia during the cooler periods may have greatly affected the formation of the genetic structure of bonobo populations.

Highlights

Bonobos (Pan paniscus) range in the forest area of the southern Congo Basin, the left bank of the Congo River (Fig 1)
The to MRCA (TMRCA) of bonobos was calculated at 0.64 million years ago (Ma) (0.50–0.79 with 95% HPD) by estimation 1 [0.95 Ma (0.70–1.22 Ma) by estimation 2; hereafter, a number in the square parenthesis means the age by estimation 2] (Table 3)
A higher mutation rate of the branch was observed after divergence from chimpanzees to the most recent common ancestor (MRCA) of bonobos in estimation 2, there were no remarkable differences in the mutation rate among each haplogroup

Summary

Introduction

Bonobos (Pan paniscus) range in the forest area of the southern Congo Basin, the left bank of the Congo River (Fig 1). Their divergence from chimpanzees (Pan troglodytes) has been estimated to be 0.8–2.1 million years ago (Ma) from genetic studies [1]. Previous genome studies on two Pan species suggested that bonobos have clearly been separated from chimpanzees [2,3]. The recent genome analysis indicated the possibility that some gene flow occurred between two species during the late Pleistocene [4].

Methods

Results

Conclusion