Date of Award
9-1-2020
Degree Name
Master of Science
Department
Zoology
First Advisor
Brown, Jason
Abstract
Knowledge of phylogenetic relationships among organisms is essential for anchoring evolutionary studies. Phylogenomic studies use large amounts of genetic data in analyses, which is particularly important for highly phenotypically variable taxa that are difficult to distinguish from one another without the use of genetic data, due to the abundance of homoplasy in morphological characters typically used in morphological classification. Use of genome-scale molecular data has thus become the gold standard for identifying these phylogenetic relationships, specifically in comparison to past studies based on fewer genes. Greater quantities of genetic data, in addition to finer taxon sampling, may lead to different conclusions about phylogenetic relationships among organisms compared to previous studies, necessitating new analyses on organisms when new discoveries of populations and new sources of genetic data arise. Ranitomeya poison frogs (Amphibia: Dendrobatidae) are an Amazonian lineage of dendrobatid frogs consisting of 16 species possessing remarkable diversity in color pattern, range size, and parental care behavior. I present the first phylogeny based on genomic data for all species in Ranitomeya, using maximum likelihood and multi-species coalescent methods. I used ultraconserved elements (UCEs), a genome-scale nuclear marker, as my source of molecular data to construct the tree. I also present divergence time estimations using the MCMCTree program. My results indicate several differences from previous analyses in terms of interspecific relationships. Notably, I find R. toraro and R. defleri constitute different species groups, and recover R. uakarii as paraphyletic. I also designate former populations of R. fantastica from Isla Pongo, Peru and Tarapoto as R. summersi, and transfer the French Guianan R. amazonica populations to R. variabilis. My study clarifies both interspecific and intraspecific relationships within Ranitomeya, and provides key insights into phylogeny that pave the way for future studies testing hypotheses on color pattern evolution and historical biogeography.
Access
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