Back to Search
Start Over
A macro-ecological perspective on crassulacean acid metabolism ( CAM) photosynthesis evolution in Afro-Madagascan drylands: Eulophiinae orchids as a case study.
- Source :
-
New Phytologist . Oct2015, Vol. 208 Issue 2, p469-481. 13p. 1 Color Photograph, 2 Charts, 3 Graphs. - Publication Year :
- 2015
-
Abstract
- Crassulacean acid metabolism ( CAM) photosynthesis is an adaptation to water and atmospheric CO2 deficits that has been linked to diversification in dry-adapted plants. We investigated whether CAM evolution can be associated with the availability of new or alternative niches, using Eulophiinae orchids as a case study., Carbon isotope ratios, geographical and climate data, fossil records and DNA sequences were used to: assess the prevalence of CAM in Eulophiinae orchids; characterize the ecological niche of extant taxa; infer divergence times; and estimate whether CAM is associated with niche shifts., CAM evolved in four terrestrial lineages during the late Miocene/Pliocene, which have uneven diversification patterns. These lineages originated in humid habitats and colonized dry/seasonally dry environments in Africa and Madagascar. Additional key features (variegation, heterophylly) evolved in the most species-rich CAM lineages. Dry habitats were also colonized by a lineage that includes putative mycoheterotrophic taxa., These findings indicate that the switch to CAM is associated with environmental change. With its suite of adaptive traits, this group of orchids represents a unique opportunity to study the adaptations to dry environments, especially in the face of projected global aridification. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 0028646X
- Volume :
- 208
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- New Phytologist
- Publication Type :
- Academic Journal
- Accession number :
- 109509739
- Full Text :
- https://doi.org/10.1111/nph.13572