A phylogenetic and ecological study showing where, and why species identification needs multiple lines of evidence.

Citation. Duran, D. P., Laroche, R. A., Gough, H. M., Gwiazdowski, R. A., Knisley, C. B., Herrmann, D. P., Roman, S. J., and Egan, S. P.. Geographic life history differences predict genomic divergence better than mitochondrial barcodes or phenotype. Genes 11 (3): 265. https://doi.org/10.3390/genes11030265

The Question. Tiger beetles in the Cicindelidia politula (LeConte, 1875) species complex show extreme phenotypic variation, within and between populations, reflected in prior taxonomy. Is phenotype the right signal for species boundaries, or does a combination of data sources define distinction?

ABC’s Contribution. Advised on analytical methods. Contributed manuscript structure, content, editing, and data visualizations.

Findings. Nuclear analyses recovered only two species, as congruent with adult life history rather than the phenotypic variation that had informed prior taxonomy. DNA barcodes alone would mislead identification in this group, because mitochondrial discordance was widespread; including a pattern of ‘mitochondrial displacement’, where mitochondria from one species unidirectionally displaced others.

For Projects Like This. ABC contributes methods work to reference libraries, eDNA programs, and other genetic identification efforts. We’re a good first call to apply systems-thinking for applied problems.