Journal Article

The first cavefish in the Dinaric Karst? Cave colonization made possible by phenotypic plasticity in Telestes karsticus

Čupić, M., Marčić, Z., Lukić, M., Gračan, R. and Bilandžija, H.

Record Number:
6238
Year:
2023
Journal:
Zoological Research
Pages:
821-833
Volume:
44
Abstract:
Cave animals are an excellent model system for studying adaptive evolution. At present, however, little is known about the mechanisms that enable surface colonizers to survive in the challenging environment of caves. One possibility is that these species have the necessary genetic background to respond with plastic changes to the pressures of underground habitats. To gain insight into this process, we conducted a comparative study with the fish species Telestes karsticus, which occurs in a hydrological system consisting of an interconnected stream and a cave. Results showed that T. karsticus resided year-round and spawned in Sušik cave, making it the first known cavefish in the Dinaric Karst. Cave and surface populations differed in morphological and physiological characteristics, as well as in patterns of gene expression without any evidence of genetic divergence. To test whether observed trait differences were plastic or genetic, we placed adult fish from both populations under light/dark or constant dark conditions. Common laboratory conditions erased all morphometric differences between the two morphs, suggesting phenotypic plasticity is driving the divergence of shape and size in wild fish. Lighter pigmentation and increased fat deposition exhibited by cave individuals were also observed in surface fish kept in the dark in the laboratory. Our study also revealed that specialized cave traits were not solely attributed to developmental plasticity, but also arose from adult responses, including acclimatization. Thus, we conclude that T. karsticus can adapt to cave conditions, with phenotypic plasticity playing an important role in the process of cave colonization
Times Cited:
1
Related Records:
Maric, Z. (2013)
Taxonomic, biological and ecological characteristics of the genus Telestes Bonaparte, 1837 (Actinopterygii) in the area of the Velika Kapela and Mala Kapela mountains [In Croatian]
Ćaleta, M., Buj, I., Mrakovčić, M., Mustafić, P., Zanella, D., Marčić, Z., Duplić, A., Mihinjač, T., Katavić, I. (2015)
Endemic fishes of Croatia.
Marčić, Z., Milković, A., Ćaleta, M., Buj, I., Zanella, D. and Mustafić, P. (2017)
Reproductive biology of the endemic dace Telestes karsticus Marčić and Mrakovčić, 2011 (Cyprinidae, Leuciscinae), in Croatia
Buj, I., Marčić, Z., Caleta, M., Sanda, R., Geiger, M.F., Freyhof, J., Machordom, A. and Vukić, J. (2017)
Ancient connections among the European rivers and watersheds revealed from the evolutionary history of the genus Telestes (Actinopterygii; Cypriniformes).
Marčić, Z., Abramović, A., Ćaleta, M., Buj, I., Zanella, D., Horvatić, S. and Mustafić, P. (2021)
Early development of the endemic dace Telestes karsticus (Leuciscidae, Cypriniformes) in a Dinaric karst stream in Croatia
Buj, I., Marcic, Z., Flauder, E., Šanda, R. and Vukic, J. (2022)
Population genetic structure of endemic fish species facilitating their survival in changing environments—A case study on the genus Telestes in Croatia
Čupić, M., Marčić, Z., Lukić, M., Gračan, R. and Bilandžija, H. (2023)
The first cavefish in the Dinaric Karst? Cave colonization made possible by phenotypic plasticity in Telestes karsticus
Berak Cihorić, D., Marić, A., Mrdak, D. and Simonović, P. (2024)
Morphometric and meristic differentiation among five populations of Delminichthys ghetaldii (Actinopterygii, Cyprinidae) from five karst fields in Eastern Herzegovina