Work

Early photosynthetic eukaryotes inhabited low-salinity habitats

Year: 2017

Type: article

Abstract: Significance Although it is widely accepted that the chrloroplasts in photosynthetic eukaryotes can be traced back to a single cyanobacterial ancestor, the nature of that ancestor remains debated. Chloroplasts have been proposed to derive from either early- or late-branching cyanobacterial lineages, and similarly, the timing and ecological setting of this event remain uncertain. Phylogenomic and Bayesian relaxed molecular clock analyses show that the chloroplast lineage branched deep within the cyanobacterial tree of life ∼2.1 billion y ago, and ancestral trait reconstruction places this event in low-salinity environments. The chloroplast took another 200 My to become established, with most extant groups originating much later. Our analyses help to illuminate the little known evolutionary history of early life on land.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.1620089114

Authors: Patricia Sánchez-Baracaldo, John A. Raven, Davide Pisani, Andrew H. Knoll

Institutions: University of Bristol, University of Technology Sydney, James Hutton Institute, University of Dundee, Harvard University

Language: English

Topic: Protist diversity and phylogeny

Subfield: Ecology, Evolution, Behavior and Systematics

Field: Agricultural and Biological Sciences

Domain: Life Sciences

Open Access status: green

Funders: Royal Society, Natural Environment Research Council

Award: Perturbation of the Earth System at the Proterozoic-Phanerozoic transition and the resilience of the biosphere