Conservation Genetics: Lab Members

Christine Edwards, PhD, Principal Investigator, Assistant Scientist for Conservation Genetics, Center for Conservation and Sustainable Development (CCSD)

Burgund Bassuner, PhD, Science Specialist, CCSD

Serena Acha, Ph.D. student at the University of Missouri St. Louis
Alex Linan, Ph.D. student at St. Louis University
Rachel Lyman, Ph.D. student at Washington University
Brigitte Williams, Ph.D. student at St. Louis University
Our Projects

Serena is interested in the angiosperms systematics and evolution. She has worked with Rosaceae, Myristicaceae and Andean flora in general. Serena is co-advised by Dr. Nathan Muchhala of the University of Missouri St. Louis and Dr. John MacDougal from Harris-Stowe State University. Serena is currently working with a group in passion flowers: Passiflora subgenus Decaloba section Decaloba that includes ~120 species distributed across America. This group of passion flowers represents an extreme challenging system to study due to their outdated taxonomic knowledge state, abundant between species micromorphological variation and the high diversity within the section. Spite of this, understanding the evolution and biogeographic processes in a scale like the current distribution of section Decaloba could help us to understand better the processes of speciation in high diverse young clades of plants. The main objective of her study is to disentangle the phylogeny, biogeography and species limits in section Decaloba. The first step to start understanding section Decaloba evolution is to build a well-supported phylogeny. For this, Serena is currently working with herbarium specimens using the 2b-RAD sequencing approach. This will allow an extensive sampling of most of the species in the group and it will most likely open the door to new discoveries and questions inside the poor understood section Decaloba species.

My research is on the origins of endemism, focusing on rare endemic flora in the cedar glades of the Central Tennessee Basin. This region is a hotspot for endemism, including around 30 rare, threatened, and endangered endemic plant species. The origin of these glades and their endemic species is unknown. It has been proposed that they formed during the Hypsithermal Interval (8,000-4,000 YPB), implying very rapid speciation. To test this hypothesis I am studying the phylogenetic and phylogeographic patterns of 12 endemic plant species by determining their closest relatives using RAD-seq, dating the timing of their origin, and identifying overall forces that could have given rise to this endemic flora. Understanding their origin what makes these species rare can provide important insights for their management and conservation.

Alex is interested in a group of long lived tree species within the ebony and persimmon genus (Diospyros) endemic to islands of the Western Indian Ocean. Specifically, he has been focusing on 12 species endemic to the island of Mauritius; A small volcanic island located approximately 900km off the coast of Madagascar. This high degree of diversity on such as small island (just ~40 x 60 km) begs a number of questions, including, whether or not the observed species diversity which is based off of morphology is truly indicative of unique species lineages. This is an important question to address as many of the Diospyros species there are threatened or endangered and by confirming species identifications, we can ensure that limited conservation funds are put toward valid species. Furthermore, by characterizing genetic diversity in these species, we may be able to direct in situ conservation efforts to ensure genetic diversity is preserved so that these species are able to adapt to changing environments. Finally, if there is truly such high levels of endemic Diospyros species diversity on Mauritius, how has this diversity arose and how is it maintained? Alex addresses these questions using next generation sequencing approaches such as 2b-RAD seq to in order to genotype large numbers of individual members of species. "

My research interests lie in understanding how species that lack genetic diversity respond to changing environmental conditions. A core assumption of evolutionary biology is that populations require genetic diversity in order to adapt and populations with low genetic diversity have a reduced capacity to adapt. However, there are many rare and common species lacking genetic diversity that persist. One mechanism of evolution that may explain this phenomenon is phenotypic plasticity (the ability of a single genotype to produce different phenotypes in different environments). I’m interested in using genetics and epigenetics to explore phenotypic plasticity in natural plant populations with the goal of assessing their ability to respond to environmental changes and adapt in situ. I hope to use this research to assist in the conservation of populations of rare, threatened, and endangered plant species.

Conservation Genetics