Convergence between the microcosms of Southeast Asian and North American pitcher plants
Abstract
The 'pitchers' of carnivorous pitcher plants are exquisite examples of convergent evolution. An open question is whether the living communities housed in pitchers also converge in structure or function. Using samples from more than 330 field-collected pitchers of eight species of Southeast Asian Nepenthes and six species of North American Sarracenia, we demonstrate that the pitcher microcosms, or miniature ecosystems with complex communities, are strikingly similar. Compared to communities from surrounding habitats, pitcher communities house fewer species. While communities associated with the two genera contain different microbial organisms and arthropods, the species are predominantly from the same phylogenetic clades. Microbiomes from both genera are enriched in degradation pathways and have high abundances of key degradation enzymes. Moreover, in a manipulative field experiment, Nepenthes pitchers placed in a North American bog assembled Sarracenia-like communities. An understanding of the convergent interactions in pitcher microcosms facilitates identification of selective pressures shaping the communities.
Data availability
Amplicon sequencing data have been deposited as NCBI BioProject PRJNA448553: https://www.ncbi.nlm.nih.gov/bioproject/PRJNA448553. Metagenomic sequencing data have been deposited in MG-RAST: http://www.mg-rast.org/linkin.cgi?project=mgp15454. The source code and data for Figures 1-5 and for Tables S3 and S4 have been deposited in a Harvard Dataverse repository: https://doi.org/10.7910/DVN/QYUBN2.
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Amplicon sequencing dataNCBI BioProject PRJNA448553.
Article and author information
Author details
Funding
National Science Foundation (NSF Graduate Fellowship and Doctoral Dissertation Improvement Grant DEB-1400982)
- Leonora S Bittleston
Templeton Foundation (Foundational Questions In Evolutionary Biology)
- Naomi E Pierce
- Anne Pringle
Harvard University Museum of Comparative Zoology Putnam Expedition Grant (Putnam Grant)
- Leonora S Bittleston
National Geographic Society
- Naomi E Pierce
University of Malaya High Impact Research Grant (UM-MOHE HIR Grant UM.C/625/1/HIR/MOHE/CHAN/14/1)
- Kok Gan Chan
National Science Foundation (SES-0750480)
- Naomi E Pierce
University of Malaya High Impact Research Grant (H-50001-A000027)
- Kok Gan Chan
University of Malaya High Impact Research Grant (A-000001-50001)
- Kok Gan Chan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Bittleston et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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