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Ideating iDNA: Lessons and limitations from leeches in legacy collections
Mark E Siddall1, Megan Barkdull2, Michael Tessler1
1Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, United States of America.
Plos One
|February 23, 2019
Summary
Invertebrate ingested DNA (iDNA) from leeches shows promise for biodiversity monitoring. Critically evaluating iDNA protocols reveals the need for better reference databases and markers to avoid biased results in faunal inventories.
Area of Science:
- Ecology and Evolutionary Biology
- Genomics
- Conservation Science
Background:
- Indirect faunal inventories using environmental DNA (eDNA) are advancing.
- Invertebrate ingested DNA (iDNA) from terrestrial leeches (Haemadipsidae) offers potential for vertebrate surveys and biodiversity monitoring in protected areas.
Purpose of the Study:
- To critically evaluate the limitations and biases of current iDNA protocols for biodiversity monitoring.
- To assess the utility of standard and Next-Generation Sequencing (NGS) barcoding approaches for iDNA analysis.
- To explore the potential of iDNA from museum specimens for temporal and cryptic diversity studies.
Main Methods:
- Analysis of ingested DNA (iDNA) from terrestrial leech samples (fresh and legacy).
- Application of standard and NGS barcoding techniques.
- Evaluation of reference database limitations and marker selection.
Main Results:
- Identified vertebrates from Myanmar, Australia, and Madagascar using iDNA from leeches.
- Highlighted the critical need for taxon-relevant multi-locus markers and comprehensive reference databases.
- Demonstrated the potential for iDNA to characterize microbial communities and pathogen diversity at low cost.
- Showcased the feasibility of using DNA from legacy museum specimens.
Conclusions:
- Current iDNA protocols require refinement, particularly regarding reference databases, to prevent biased biodiversity assessments.
- iDNA from leeches, including museum specimens, is a cost-effective tool for surveying vertebrates, microbial communities, and cryptic diversity.
- Future research should focus on developing improved markers and databases for robust iDNA-based faunal inventories.
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