Abstract Detail

Pteridology

Riibe, Lindsey [1], Sessa, Emily [2].

Phylogeny and biogeography of endemic ferns in a biodiversity hotspot.

The diversity of tropical islands has intrigued biologists for centuries and has inspired myriad hypotheses about the processes of evolution ever since Darwin’s formulation of the theory of natural selection. Islands provide unique opportunities for asking questions about diversification processes, biogeographic patterns, and evolution in isolated or semi-isolated systems. While much work in the past decades has illuminated many aspects of evolution on islands, there is much we still do not know. My proposed study draws on phylogenetic and biogeographical analyses to better understand the evolutionary history of and drivers for insular fern diversity. Polystichum (Dryopteridaceae) is a large and taxonomically complicated genus of ferns with exceptional diversity in the Neotropics. The West Indies, a global biodiversity hotspot and most significant island system in the New World tropics, is a center of diversity for the genus with 31 species found on the islands, 94% of which are endemic. I plan to use the Neotropical species of Polystichum to investigate patterns of dispersal, reticulate evolution, and diversification, focusing on the species of the West Indies, to understand how and why some species become widespread while others remain endemic to individual islands. Including nuclear markers in my study will allow for downstream analyses focused on reticulate evolution within the group, looking at how genome duplication has shaped fern diversity in the West Indies. Many of the taxa for this project are single-island endemics with small populations and limited ranges, increasing their extinction risk. Another outcome of this project will be the collection of spores for ex-situ conservation and propagation, which I will undertake in collaboration with the Fairchild Tropical Botanic Garden, which has extensive experience conserving rare ferns. Additionally, I will use the molecular phylogeny from this study to clarify taxonomic uncertainties in Polystichum, so that government agencies can better allocate funding and conservation priorities. Therefore, this project will not only enhance our understanding of fern systematics and the processes that underlie insular diversity, but simultaneously work to conserve one of the world’s most important biodiversity hotspots.

1 - University of Florida, Biology, Gainesville, FL, 32611, USA
2 - University Of Florida, Gainesville, FL, 32611, United States

Keywords:
ferns
island biogeography
West Indies
reticulate evolution
Conservation
Phylogenetics
long distance dispersal.

Presentation Type: Poster
Session: P, Pteridology
Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 5:30 PM This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPT001
Abstract ID:169
Candidate for Awards:None