Diversification of African tree frogs (genus Leptopelis) in the highlands of Ethiopia

Abstract

The frog genus Leptopelis is composed of ~50 species that occur across sub-Saharan Africa. The majority of these frogs are typically arboreal; however, a few species have evolved a fossorial lifestyle. Most species inhabit lowland forests, but a few species have adapted to high elevations. Five species of Leptopelis occupy the Ethiopian highlands and provide a good opportunity to study the evolutionary transition from an arboreal to a fossorial lifestyle, as well as the diversification in this biodiversity hot spot. We sequenced 14 nuclear and three mitochondrial genes, and generated thousands of SNPs from ddRAD sequencing to study the evolutionary relationships of Ethiopian Leptopelis. The five species of highland Leptopelis form a monophyletic group, which diversified during the late Miocene and Pliocene. We found strong population structure in the fossorial species L. gramineus, with levels of genetic differentiation between populations similar to those found between arboreal species. This could indicate that L. gramineus is a complex of cryptic species. We propose that after the original colonization of the Ethiopian highlands by the ancestor of the L. gramineus group, episodes of vicariance fragmented the ancestral populations of this group. We also report the re-evolution of arboreality in L. susanae, which evolved from a fossorial ancestor, a rare ecological switch in frogs that had previously been reported only once.

Up in the air: threats to Afromontane biodiversity from climate change and habitat loss revealed by modelling and landscape genetics of the Ethiopian Highlands long-eared bat

“…All clades, except the Bale population that included deeply divergent basal lineages, could be the result of isolation processes relating to older glacial cycles during the Pleistocene. These episodes of allopatric isolation appear as the main driver of differentiation in Ethiopian highland vertebrates (Reyes-Velasco et al, 2018). The phylogeographic structure of P. balensis is consistent with that of the Ethiopian wolf (Gottelli et al, 2004), whereby three main clusters are present corresponding to the three well-defined mountain areas: the southern Chilalo/Bale, the central Guassa/Abune Yosef and the northern isolated Siemen Massifs.…”

“…It played a major role in structuring biodiversity across Eastern Africa, from the Afroalpine plantsArabis alpine (Asefa, Ehrich, Taberlet, Nemomissa, & Brochmann, 2007) and Lobelia giberroa (Kebede, Ehrich, Taberlet, Namomissa, & Brochmann, 2007) to most of Ethiopian anurans (Freilich et al, 2016), including the high altitude African clawed frogs, Xenopussp. (Evans, Bliss, Mendel, & Tinsley, 2011) and the forest tree frogs (Reyes-Velasco et al, 2018). Interestingly, amphibians found at elevations below 2500 masl did not show differences between the northern and southern highland massifs (Freilich et al, 2016).…”

“…The complex geological history of the Ethiopian highlands is partially responsible for its high biodiversity and endemism. The highlands do not constitute a single unit, but instead are formed by various massifs of different areas, origins, ages and degrees of isolation (Reyes-Velasco et al, 2018). Genomic differentiation in highland species, like the river frog, Amietia nutti , is explained not only by the Rift Valley but also by other major geographical barriers, the Blue Nile Valley and the Omo River (Manthey, Reyes-Velasco, Freilich, & Boissinot, 2017).…”

“…The Afroalpine biome shows one of the highest rate of endemism in the world due to a combination of their relative small areas, high isolation and climatic history (Reyes-Velasco, Manthey, Freilich, & Boissinot, 2018;S. D. Williams et al, 2004).…”

What Is (Not) a Baboon?

“…However, many popular sources now go out of their way to correct the misunderstanding that mandrills are baboons (e.g., http://www.monkeyworlds.com/mandrill/). The application of Bbaboonĉ urrently extends beyond the genus Papio mainly to the genus Theropithecus, as the gelada continues to be called the Bgelada baboon^in scientific publications, including in primatology journals (e.g., Abie et al 2017;Espinosa-Gómez et al 2018;Reyes-Velasco et al 2018;Thompson and Georgiev 2014).…”