A multilocus phylogeny reveals deep lineages within African galagids (Primates: Galagidae)

Abstract

BackgroundBushbabies (Galagidae) are among the most morphologically cryptic of all primates and their diversity and relationships are some of the most longstanding problems in primatology. Our knowledge of galagid evolutionary history has been limited by a lack of appropriate molecular data and a paucity of fossils. Most phylogenetic studies have produced conflicting results for many clades, and even the relationships among genera remain uncertain. To clarify galagid evolutionary history, we assembled the largest molecular dataset for galagos to date by sequencing 27 independent loci. We inferred phylogenetic relationships using concatenated maximum-likelihood and Bayesian analyses, and also coalescent-based species tree methods to account for gene tree heterogeneity due to incomplete lineage sorting.ResultsThe genus Euoticus was identified as sister taxon to the rest of the galagids and the genus Galagoides was not recovered as monophyletic, suggesting that a new generic name for the Zanzibar complex is required. Despite the amount of genetic data collected in this study, the monophyly of the family Lorisidae remained poorly supported, probably due to the short internode between the Lorisidae/Galagidae split and the origin of the African and Asian lorisid clades. One major result was the relatively old origin for the most recent common ancestor of all living galagids soon after the Eocene-Oligocene boundary.ConclusionsUsing a multilocus approach, our results suggest an early origin for the crown Galagidae, soon after the Eocene-Oligocene boundary, making Euoticus one of the oldest lineages within extant Primates. This result also implies that one – or possibly more – stem radiations diverged in the Late Eocene and persisted for several million years alongside members of the crown group.

Primate phylogenetic relationships and divergence dates inferred from complete mitochondrial genomes

“…Within lorisoids, our mitogenomic tree places Asian lorisids as the sister group to the African galagids rather than to the African lorisid Perodicticus . Both the lorisids and the papionins are well supported by morphological data and nuclear sequences, and previous studies employing mitochondrial sequences have shown similar difficulty in recovering such clades (Papionini: Disotell et al, 1992; Harris, 2000; Finstermeier et al, 2013; Lorisidae: Roos et al, 2004; Masters et al, 2007; Matsui et al, 2009; Finstermeier et al, 2013; Pozzi et al, accepted ). The mitochondrial genome represents a single locus and its phylogenetic history can differ from the species as a consequence of several events, including gene flow, hybridization, or incomplete lineage sorting (Maddison, 1997; Degnan and Rosenberg, 2006; Maddison and Knowles, 2006; Edwards, 2009).…”

The role of forest expansion and contraction in species diversification among galagos (Primates: Galagidae)

“…Phylogenetic relationships and divergence times within galagids are consistent with recent studies using either mitochondrial (Pozzi et al, 2015) or nuclear DNA (Pozzi et al, 2014a). Missing data did not significantly impact the overall results, suggesting that the topology and divergence dates presented in this study are robust.…”

“…Galagids are widely distributed across most of sub-Saharan Africa and inhabit a large range of diverse habitats including lowland rain forests, montane forests, and open woodlands and savannas (Nekaris & Bearder, 2010;Nekaris, 2013). As the two earliest branching lineages (Euoticus and western Galagoides) are both central African lineages, Pozzi et al (2014a) hypothesized a biogeographical origin in central-western Africa. Recent studies have suggested old origins for this family, dating back to roughly 30 Ma at the very beginning of the Oligocene (Pozzi et al, 2014a(Pozzi et al, , 2015.…”

“…While some genera have restricted distributions in the tropical forests of central Africa (Euoticus and Sciurocheirus), other genera are more widespread across Africa (Galago and Otolemur). Recent studies have suggested old origins for this family, dating back to roughly 30 Ma at the very beginning of the Oligocene (Pozzi et al, 2014a(Pozzi et al, , 2015. As the two earliest branching lineages (Euoticus and western Galagoides) are both central African lineages, Pozzi et al (2014a) hypothesized a biogeographical origin in central-western Africa.…”

Vocal activity of lesser galagos (Galagospp.) at zoos

“…Lesser galagos include four extant species that are widespread in sub‐Saharan Africa [Butynski et al, ]. They show a lack of overt morphological diversity, which, together with the still unresolved taxonomy of the genus and the whole Galagidae family [Kingdon, ; Butynski et al, ; Pozzi et al, ], complicates their correct determination and thus their breeding management at zoos. Previously, some of their vocalizations, especially the advertisement call, have been demonstrated to significantly contribute to species determination [Zimmermann et al, ; Zimmermann, ].…”