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Modeling the Size Spectrum for Macroinvertebrates and Fishes in Stream Ecosystems
Published on: July 30, 2019
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Genome size variation in deep-sea amphipods.
H Ritchie1, A J Jamieson2, S B Piertney1
1Institute of Biological and Environmental Sciences, University of Aberdeen, Zoology Building, Aberdeen AB24 2TZ, UK.
Royal Society Open Science
|October 10, 2017
Summary
Deep-sea amphipod genome sizes vary nine-fold, challenging the idea that extreme environments universally promote larger genomes. Body size, particularly gigantism, influences genome size, but doesn't explain all observed variation.
Area of Science:
- Marine Biology
- Genomics
- Evolutionary Biology
Background:
- Genome size variation is a key area of evolutionary research.
- The deep sea's extreme conditions are hypothesized to correlate with larger eukaryotic genome sizes.
Purpose of the Study:
- To investigate genome size variation in deep-sea amphipods.
- To test the hypothesis that extreme deep-sea environments promote larger genome sizes.
Main Methods:
- Genome sizes were measured in 13 deep-sea amphipod species using flow cytometry.
- Phylogenetic independent contrast analysis was employed to examine trait relationships.
Main Results:
- Genome sizes varied nine-fold across the studied species, from 4.06 pg to 34.79 pg.
- A correlation between genome size and maximum body size was found, primarily driven by gigantism.
- A significant shift in genome size diversification rate was observed in the supergiant amphipod *Alicella gigantea*.
Conclusions:
- Observed genome size variation in deep-sea amphipods is substantial and not solely explained by common evolutionary history or niche.
- Body size, especially gigantism, is a factor, but doesn't account for the full spectrum of genome size diversity in these organisms.
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