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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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Paraphyletic relationships revealed by mitochondrial DNA in the Peromyscus mexicanus species group (Rodentia: Cricetidae)
Although deer mice (Peromyscus spp.) are among the most studied small mammals, their species diversity and phylogenetic relationships remain unclear. The lack of taxonomic clarity is mainly due to a conservative morphology and because some taxa are rare, have restricted distributions, or are poorly sampled. One taxon, P. mexicanus, includes southern Mexican subspecies that have not had their systematic placement tested with genetic data. We analyzed the phylogenetic relationships and genetic structure of P. mexicanus populations using sequences of the mitochondrial gene cytochrome b. We inferred that P. mexicanus is paraphyletic, with P. m. teapensis, P. m. tehuantepecus, andP. m. totontepecus more closely related to P. gymnotis than to P. m. mexicanus. This highly divergent clade ranges from northeastern Oaxaca to northern Chiapas, including southern Veracruz, and southern Tabasco. In light of this group’s mitochondrial distinctiveness, cohesive geographic range, and previously reported molecular, biochemical, and morphological differences, we recommend it be treated as P. totontepecus. Our findings demonstrate the need for an improved understanding of the diversity and evolutionary history of these common and abundant members of North American small mammal communities.
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- Award ID(s):
- 1754393
- PAR ID:
- 10405279
- Date Published:
- Journal Name:
- Revista Mexicana de Biodiversidad
- Volume:
- 93
- ISSN:
- 1870-3453
- Page Range / eLocation ID:
- e933811
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.22201/ib.20078706e.2022.93.3811
