Conference Paper
As above, so below? Testing for gene flow between cave and surface-dwelling populations of Garra barreimiae
Kirchner, S., Sattmann, H., Plan, L., Krenn, H., Victor, R., Haring, E. and Kruckenhauser, L.
Record Number:
3896
Year:
2016
Abstract:
Garra barreimiae is a cyprinid freshwater fish endemic to the southeastern Arabian Peninsula, where it inhabits regularly desiccating water bodies. A hypogean population with troglomorphic traits found in the Al Hoota cave system in northern Oman is considered as conspecific with the normally developed surface morphotypes. Normally the fish live in quiet cave pools but after heavy rain the cave is flushed and limited contact with the surface population is likely. Therefore G. barreimiae is a perfect organism to study the effects of life in complete darkness and mechanisms of adaption.
The DNA-study of Kruckenhauser et al. (2011) based on a section of the mitochondrial control region showed that specimens from the cave population are genetically differentiated from the adjacent surface populations. Some surface individuals possess haplotypes characteristic for the cave population and most of these individuals display intermediate phenotypes. These results suggest a quite recent separation of the cave population. For a better understanding of the evolution of the troglomorphic phenotype it is crucial to know if and to what extent gene flow between these morphotypes occurs. Hence, we investigated individuals from two troglomorphic cave populations (including Al Hoota), one cave with constant water outflow giving connection to the surrounding surface water body and two surface sites. In order to estimate potential gene flow between cave and surface populations we utilized 19 variable microsatellite markers designed specifically for G. barreimiae (Kirchner et al. 2014). The results show that both caves inhabited by troglomorphic fish are clearly separated from the surface populations. Some of the specimens with intermediate phenotypes possess a hybrid genotype, while others are genetically clearly of cave origin. For the latter, it can be assumed that cave fish were washed out during floods and the intermediate phenotype is a result of phenotypic plasticity induced by light exposure.
Times Cited:
1
Conference Name:
23rd International Conference on Subterranean Biology
Conference Year:
2016
Conference Location:
2016
Conference Location:
2016
Relevent Species: