PhD Student
Advisor: Luise Kruckenhauser

Unit for integrative Zoology, Department of Evolutionary Biology, University of Vienna
& Natural History Museum Vienna

Abstract

Adaptation to the extreme, static conditions of caves—such as total darkness and nutrient scarcity—provides a unique opportunity to study evolutionary mechanisms at play. Garra longipinnis, a fish species from the Hajar Mountains of Oman, exists in two distinct morphotypes: an epigean form in surface waters and a cave-dwelling form living in the perpetual darkness of local cave systems. The latter exhibits classic troglomorphic traits, including eye loss and reduced body pigmentation. These phenotypic changes raise a central question in cave biology research: are such traits the result of relaxed selective pressures and fixation through genetic drift, or do they confer selective advantages in dark, nutrient-poor environments? Understanding the evolutionary forces shaping these traits i.e. degeneration versus adaptation, can provide insights into how organisms respond to extreme habitats. As a species with both surface and cave populations, Garra longipinnis represents a promising model system for comparative studies, offering a valuable view into the genetic and evolutionary processes that drive divergence in isolated environments