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  • Conservation implications for the world’s most widely distributed cavefish species complex based on population genomics (Typhlichthys, Percopsiformes)
Title: Conservation implications for the world’s most widely distributed cavefish species complex based on population genomics (Typhlichthys, Percopsiformes)
Cave-obligate aquatic organisms are difficult to monitor for conservation due to cryptic diversity, unknown subterranean hydrological connectivity, and accessibility to habitats. Conservation management practices have benefitted from evolutionary data; however, the evolutionary and biogeographic histories of most cave-obligate organisms are unknown. The modes and patterns leading to most cave-obligate organism distributions are also uncertain. The Southern Cavefish (Typhlichthys subterraneus, Amblyopsidae) is the largest ranging cavefish in the world but represents a species complex of which the distribution and relatedness within remains unclear. To explore modes of cave-adaptive evolution, we performed population genomic analyses on a dataset of single nucleotide polymorphisms harvested from ultraconserved elements. We found five to eight strongly delineated genetic clusters. Little to no genetic exchange occurred between clusters, indicating high genetic distinctiveness and low connectivity, a concerning result for the fitness and conservation of these fishes. Genetic clusters did not correspond to caves nor to other geographic boundaries examined. Unfortunately, one of the geographic units most easily communicated for conservation– caves– do not match the biological units of interest. Our results support multiple independent colonization events from a widespread surface ancestor with a small degree of cave connectivity among, but not between, clusters. We suggest whole cave system conservation.  more » « less
Award ID(s):
2047939
PAR ID:
10528167
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Conservation Genetics
Volume:
25
Issue:
1
ISSN:
1566-0621
Page Range / eLocation ID:
165 to 177
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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