Open AccessAncient landscapes of the Namib Desert harbor high levels of genetic variability and deeply divergent lineages for Collembola
Author(s) -
Collins Gemma E.,
Hogg Ian D.,
Baxter Janine R.,
MaggsKölling Gillian,
Cowan Don A.
Publication year - 2019
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.5103
Subject(s) - biology , biological dispersal , ecology , gene flow , genetic diversity , disjunct , genetic divergence , coalescent theory , dna barcoding , cytochrome c oxidase subunit i , genetic variation , mitochondrial dna , phylogenetics , gene , population , biochemistry , demography , sociology
Aim To assess spatial patterns of genetic and species‐level diversity for Namib Desert Collembola using mitochondrial DNA cytochrome c oxidase subunit I (COI) gene sequences. Location Namib Desert gravel plains. Taxon Collembola (springtails). Methods A total of 77 soil samples were collected along NE‐SW (60 km) and E‐W (160 km) transects from within a 4,000 km 2 area of the Namib Desert gravel plains. We extracted 434 springtails from the 37 samples which contained Collembola and sequenced them at the COI gene locus. In the absence of specific taxonomic keys and previous genetic data for these taxa, we used Generalized Mixed Yule Coalescent (GMYC) analyses to provide putative species‐level designations. Results We obtained 341 successful COI sequences, 175 of which were unique haplotypes. GMYC analyses identified 30 putative species, with up to 28% sequence divergence (uncorrected p‐distance). The distribution of genetic variants was disjunct, with 97% of haplotypes and 70% of “GMYC species” found only at single sites. Main conclusions Dispersal events, although rare, may be facilitated by environmental events such as prevailing onshore winds or occasional flow of rainwater to the coast. We conclude that the high genetic diversity we observed is the result of ancient springtail lineages, patchy distribution of suitable habitats, and limited dispersal (gene flow) among habitable locations.