Journal Article
Flexibility of life to survive limitations: oral disc forms in the Tashan Cave barb Garra tashanensis
Segherloo, I.H., Chaloshtory, S.N., Yasser, A.G., Naser, M.D., Normandeau, E., Mashtizadeh, A., Elmi, A., Sedighi, O., Changizi, A., Hallerman, E. and Bernatchez, L.
Record Number:
6309
Year:
2023
Journal:
Environmental Biology of Fishes
Pages:
yy
Volume:
xx
Abstract:
Abstract In this study, we analyzed nuclear DNA
(nDNA) variation by means of genotyping-bysequencing
(GBS) of three disc-bearing and seven
non-disc-bearing Garra tashanensis from the Tashan
Cave in Iran to clarify their systematic and ecological
relationships. We performed genetic differentiation,
NeighborNet, Admixture, and principal component
analyses on genomic data. Admixture and principal
component analyses revealed clear genetic differentiation
between disc-bearing and non-disc-bearing
morphotypes, which was not detected by mtDNA
markers in previous work. However, there was a
non-disc-bearing individual that clustered with discbearing
individuals. Based on the results of this study,
the most parsimonious justification for coexistence of
disc-bearing and non-disc-bearing forms of Garra in
Tashan Cave is a combination of mechanisms similar
to character release (intra-specific morphological
diversification to exploit a wider range of habitats
in the absence of competitors or predators) and
relaxed selection (no more selective advantage for a
previously advantageous trait as a result of ecological
changes). The detected genetic structure may be an
indication of reproductive isolation between the two
groups. These data imply that the respective forms
of the Tashan Cave barb could be a case of ongoing
sympatric speciation, but also that disc form cannot be used as a taxonomic character for Tashan Cave barb forms.
Keywords Tashan Cave barb · Genome · Character release · Relaxed selection · Radiation
Times Cited:
2