Abstract Detail

Plant life in Neotropical rocky outcrops

de Souza Cortez, Maria Beatriz [1], Folk, Ryan [2], Grady, CJ [3], Stewart, Aimee [3], Spoelhof, Jonathan [4], Smith, Stephen A. [5], Soltis, Douglas [6], Soltis, Pamela [7].

Is the occurrence of ancient angiosperms associated with old, climatically stable and infertile landscapes in Brazil?

Old, climatically stable and infertile landscapes (OCBILs) have been hypothesized to harbor an elevated number of ancient lineages and may have originated when Gondwana was intact. OCBIL landscapes, interspersed with YODFELS (young, disturbed, fertile landscapes) and OCFELS (old, climatically stable, fertile landscapes), are predicted to occur across the globe including Southwestern and Eastern Australia, the Cerrado and Mata Atlântica in Brazil, and the Cape and Madagascar in Africa. They are also thought to coincide with commonly recognized biodiversity hotspots. The campos rupestres in Brazil constitute a vegetation type occurring discontinuously across the Cerrado, Mata Atlântica and Caatinga and are thought to represent the typical OCBIL landscape, occupying weathered highlands dating from the Precambrian dominated by rocky outcrops and grasslands, where poor soils and harsh environmental characteristics prevail. Moreover, Gondwanan lineages, such as Eriocaulaceae, Velloziaceae and Xyridaceae are very diverse and species-rich in the campos rupestres. These lines of evidence suggest that an association between ancient angiosperm lineages and old climatically stable and infertile landscapes (such as the campos rupestres) may in fact be real. The goal of this study is to test the OCBIL theory by assessing whether the occurrence of communities enriched for ancient angiosperm lineages is preferentially associated with climatic stability and poor soil environments. We conducted linear and multiple regression analyses using environmental variables and phylogenetic age estimates for seed plants and focused on comparing OCBIL and non-OCBIL landscapes in South America, particularly Brazil. We used a measure of climate stability using paleoclimatic reconstructions with soil composition, elevation and current-day climate in conjunction with several metrics quantifying plant community ages. An association between ancient angiosperm lineages and OCBIL landscapes would be supported if environmental variables characteristic of OCBILs were highly and significantly correlated with older community ages.

1 - University Of Florida, Florida Museum Of Natural History�Dickinson Hall, 1659 Museum Road, Room 357, Gainesville, FL, 32611, United States
2 - Mississippi State University, 295 E. Lee Blvd., P.O. Box GY, 295 E. Lee Blvd., P.O. Box GY, Mississippi State, MS, 39762, United States
3 - Biodiversity Institute, University of Kansas, 1345 Jayhawk Blvd, Lawrence, KS, 66045, United States
4 - University Of Florida, Florida Museum Of Natural History, Dickinson Hall, 1659 Museum Road, Gainesville, FL, 32611, United States
5 - University of Michigan, Dept. Ecology and Evolutionary Biology, 1105 N University Ave, Smith 3060, Ann Arbor, MI, 48109-1085, USA
6 - University Of Florida, Florida Museum Of Natural History, Dickinson Hall, Gainesville, FL, 32611, United States
7 - University Of Florida, Florida Museum Of Natural History, Po Box 117800, Gainesville, FL, 32611, United States

Keywords:
OCBIL
campos rupestres
Brazil
ancient angiosperms.

Presentation Type: Colloquium Presentations
Session: COL08, Plant life in Neotropical rocky outcrops
Location: Virtual/Virtual
Date: Friday, July 31st, 2020
Time: 10:30 AM
Number: COL08002
Abstract ID:740
Candidate for Awards:None