Date of Award

2015-01-01

Degree Name

Master of Science

Department

Biological Sciences

Advisor(s)

Eli B. Greenbaum

Abstract

African snake-eyed skinks are relatively small lizards of the genera Panaspis and Afroablepharus. The allocation of these genera was frequently rearranged in the 20th century based on morphology, ecology and biogeography. Members of these genera occur primarily in savanna habitats throughout sub-Saharan Africa and include species that have highly conserved morphology, which poses a challenge for taxonomic studies. We sequenced two mitochondrial (16S and cyt b) and two nuclear genes (PDC and RAG1) from 91 Panaspis and Afroablepharus samples from various localities in eastern, central and southern Africa. Concatenated gene-tree and divergence dating analyses were conducted to infer phylogenies and biogeographic patterns. Molecular data sets revealed several cryptic lineages, with most radiations occurring during the mid-Miocene to Pliocene. We infer that rifting processes (including the formation of the East African Rift System) and climatic oscillations contributed to the expansion of savannas and precipitated cladogenesis in snake-eyed skinks. Species in Panaspis and Afroablepharus used in this study, including type species for both genera, formed a monophyletic group. As a result, the latter genus is synonymized with the former, which has taxonomic priority. Divergence estimates and cryptic speciation patterns of snake-eyed skinks were consistent with previous studies of other savanna vertebrate lineages from the same areas examined in this study.

Language

en

Provenance

Received from ProQuest

File Size

70 pages

File Format

application/pdf

Rights Holder

Maria Fernanda Medina

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