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Understanding global patterns of genetic diversity (GD) is essential to describe, monitor, and preserve the processes giving rise to life on Earth. To date, efforts to map macrogenetic patterns have been restricted to vertebrate groups that comprise a small fraction of Earth’s biodiversity. Here, we construct the first global map of predicted insect genetic diversity. We calculate the global distribution of GD mean (GDM) and evenness (GDE) of insect assemblages, identify the global environmental correlates of insect GD, and make predictions for undersampled regions. Based on the largest and most species-rich single-locus genetic dataset assembled to date, we find that both GD metrics follow a bimodal latitudinal gradient, where GDM and GDE correlate with contemporary climate variation. Our models explain 1/4 and 1/3 of the observed variation in GDM and GDE in insects, respectively, making an important step towards describing global biodiversity patterns in the most diverse animal taxon.
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Global determinants of insect mitochondrial genetic diversity
Abstract Understanding global patterns of genetic diversity is essential for describing, monitoring, and preserving life on Earth. To date, efforts to map macrogenetic patterns have been restricted to vertebrates, which comprise only a small fraction of Earth’s biodiversity. Here, we construct a global map of predicted insect mitochondrial genetic diversity from cytochrome c oxidase subunit 1 sequences, derived from open data. We calculate the mitochondrial genetic diversity mean and genetic diversity evenness of insect assemblages across the globe, identify their environmental correlates, and make predictions of mitochondrial genetic diversity levels in unsampled areas based on environmental data. Using a large single-locus genetic dataset of over 2 million globally distributed and georeferenced mtDNA sequences, we find that mitochondrial genetic diversity evenness follows a quadratic latitudinal gradient peaking in the subtropics. Both mitochondrial genetic diversity mean and evenness positively correlate with seasonally hot temperatures, as well as climate stability since the last glacial maximum. Our models explain 27.9% and 24.0% of the observed variation in mitochondrial genetic diversity mean and evenness in insects, respectively, making an important step towards understanding global biodiversity patterns in the most diverse animal taxon.
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- Award ID(s):
- 2104147
- PAR ID:
- 10449688
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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