Abstract Detail



Tropical Biology

Jantzen, Johanna [1], Freitas Oliveira, Ana Luiza [2], Soltis, Douglas [3], SOLTIS, PAMELA S. [4].

Diversification and niche evolution in Neotropical Tibouchina s.s. (Melastomataceae).

The Neotropics contain around 37% of global plant diversity; two understudied Neotropical biodiversity hotspots with extremely high levels of endemism are the Cerrado (tropical savanna) and the campos rupestres (“rocky fields”). Contributing to the plant diversity of these ecoregions are certain lineages of Melastomataceae, including the paraphyletic genus Tibouchina Aubl., which occurs in these open habitats across a range of soil types, temperatures and elevations. This study investigates the prevalence of ecological divergence and the impact of niche evolution on the diversification of Tibouchina s.s., a Neotropical clade comprising 23 species that are primarily restricted to the Cerrado and campos rupestres, including both widespread and narrowly endemic species. To investigate the extent of ecological niche shifts within this clade, we constructed ecological niche models in MaxEnt for each species using herbarium records from GBIF, iDigBio, and speciesLink, climate variables from WorldClim and soil variables from SoilGrid. Predicted niche occupancy profiles show ecological divergence for specific environmental variables, and geographic projections show that although there are some areas of projected overlap in geographic space, a number of species of Tibouchina occupy distinct niches. Future studies will use these models and a well-resolved phylogeny for this clade to reconstruct niches for ancestral nodes on the phylogeny to examine the effects of ecological niche shifts on diversification. As a part of a broader research study, this project is a case study on the impact of niche evolution in the diversification of individual plant clades, helping clarify general patterns in Neotropical plant diversification.


1 - University Of Florida, Biology, Dickinson Hall, 1659 Museum Road, Gainesville, FL, 32611, United States
2 - UNESP Rio Claro, Instituto de Biociencias, Av. 24A, 1515- Bela Vista, Rio Claro, Sao Paulo, Brazil
3 - University of Florida, Biology, Gainesville, FL
4 - University Of Florida, Florida Museum Of Natural History, Gainesville, FL, 32611.0, United States

Keywords:
Cerrado
Campos rupestres
Melastomataceae
ecological niche modeling.

Presentation Type: Poster
Number: PTB002
Abstract ID:328
Candidate for Awards:None


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