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Updated: Jun 3, 2026
05:18
Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions
Published on: July 22, 2016
Genome size evolution at the speciation level: the cryptic species complex Brachionus plicatilis (Rotifera)
Claus-Peter Stelzer1, Simone Riss, Peter Stadler
1Austrian Academy of Sciences, Institute for Limnology, 5310-Mondsee, Austria. claus-peter.stelzer@oeaw.ac.at
BMC Evolutionary Biology
|April 9, 2011
Summary
Genome size variation in the rotifer Brachionus plicatilis species complex shows high diversity, even within species. This suggests rapid genome evolution during early speciation events.
Area of Science:
- Evolutionary biology
- Genomics
Background:
- Genome size variation studies are scarce at lower taxonomic levels.
- Such variation offers insights into genome evolution dynamics.
- The Brachionus plicatilis cryptic species complex presents a model for studying this variation.
Purpose of the Study:
- To investigate genome size evolution within the Brachionus plicatilis species complex.
- To quantify genome size variation at different taxonomic levels.
Main Methods:
- Utilized flow cytometry to measure genome size.
- Analyzed variation across major clades, genealogical species, and reproductively isolated pairs.
Main Results:
- Discovered a seven-fold variation in haploid genome size (0.056-0.416 pg).
- Variation attributed to major clades (67%) and lower taxonomic levels (32%).
- Observed potential whole-genome duplications in B. 'Austria' and correlations with egg and body size.
Conclusions:
- Significant genome size variation arises early in speciation, possibly in isolated populations.
- Reproductive isolation may evolve slowly within this species complex.
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