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Microbiome reduction and endosymbiont gain from a switch in sea urchin life-history

Cite this dataset

Carrier, Tyler et al. (2021). Microbiome reduction and endosymbiont gain from a switch in sea urchin life-history [Dataset]. Dryad.


Animal gastrointestinal tracts harbor a microbiome that is integral to host function, yet species from diverse phyla have evolved a reduced digestive system or lost it completely. Whether such changes are associated with alterations in the diversity and/or abundance of the microbiome remains an untested hypothesis in evolutionary symbiosis. Here, using the life-history transition from planktotrophy (feeding) to lecithotrophy (non-feeding) in the sea urchin Heliocidaris, we demonstrate that the lack of a functional gut corresponds with a reduction in microbial community diversity and abundance as well as the association with a diet-specific microbiome. We also determine that the lecithotroph vertically transmits a Rickettsiales that may complement host nutrition through amino acid biosynthesis and influence host reproduction. Our results indicate that the evolutionary loss of a functional gut correlates with a reduction in the microbiome and the association with an endosymbiont. Symbiotic transitions can thus accompany life-history transitions in the evolution of developmental strategies.


  1. Total DNA extraction
  2. Ampylificaiton of the 16S rRNA gene for bacteria using primers for the V3/V4 region
  3. Sequencing via MiSeq


Human Frontier Science Program Award, Award: RGY0079/2016

National Science Foundation, Award: IOS 1456778

National Institute of Allergy and Infectious Diseases, Award: R01 AI132581

Australian Research Council, Award: DP120102849