The transition from the Pleistocene to the Holocene was a dynamic period characterized by a series of climatic and ecological changes that influenced the way of life of hunter-gatherer populations. During this period, the eastern Adriatic coast gradually underwent geomorphological transformations, losing a large part of its landmass. The submergence of the Adriatic plain led to the loss of grassy steppes with mixed low vegetation for ungulates. The gradual isolation of the island of Dugi otok and nearby islands from the mainland limited the migrations of larger herbivores towards the todays islands. On the other hand, marine resources became increasingly accessible, so it can be assumed, based on the revolution of a broad spectrum and optimal foraging theory, since their representation increased towards younger periods. Taking into account the described changes, the main hypothesis of this research is that the Late Pleistocene and Early Holocene hunter-gatherers in the eastern Adriatic adapted to the changing environmental conditions by exploiting smaller mammals and molluscs due to the decreased availability of larger herbivores. The aim of the research is to understand the adaptive capabilities of the Late Pleistocene and Early Holocene communities through changes in diet, from hunting and gathering methods to food preparation. For the purpose of this doctoral thesis, the bone remains of mammals from Pleistocene layers (5 and 4), as well as the remains of molluscs, crabs, and sea urchins from Pleistocene (5 and 4) and Holocene layers (3 and 2) in the Vlakno cave on Dugi otok (Dalmatia, Croatia) were analyzed. The faunal remains underwent taxonomic and taphonomic analysis. The energy input of identified prey from Vlakno was estimated based on the kilocalories they provided. The results of the analysis provide insights into the paleoecological picture, changes in prey/food selection, survival strategies, and the use of the cave during the transition from the Pleistocene to the Holocene. The purpose of this discussion is to outline the subsistence patterns of the huntergatherer groups that used this archaeological site, searching for changes or continuities in the strategiesfor the preparation and consumption of mammals and molluscs in the different layers. Based on the paleoecological and palaeoeconomic data from the faunal assemblage from Vlakno, an estimate was made of the importance of different terrestrial and marine animal resources in the late Pleistocene and early Holocene. Paleoecological indicators suggest that the environment near Vlakno, i.e., Dugi otok, has changed from the Late Pleistocene to the Holocene. The Late Pleistocene fauna from the Vlakno cave indicates a greater availability of open forests and steppe areas. The rising sea level and gradual submergence of the low-lying areas are also reflected in the changing set of animal remains in Vlakno. Large herbivores (bovids, equids) that inhabited steppe expanses are absent in the Holocene layers, and the representation of species inhabiting open areas with groves increases. The changes recorded in the paleoecology of Vlakno are identical to those found in the rest of the eastern Adriatic coast. According to malacological samples, the immediate vicinity of the cave was characterized by more open and karst areas in the early Holocene. Comparing the Pleistocene and Holocene layers, there is a clear difference in prey selection. The Pleistocene layers abound with remains of red deer (Cervus elaphus), along with foxes (Vulpes vulpes) and hares (Lepus europaeus), and significant sources of meat are also represented by bovids and equids. In the Holocene layers, small game becomes more prevalent, and the more frequent use of marine resources (marine molluscs and fish) indicates a gradual adaptation of hunter-gatherer communities by expanding their food base. The treatment of large herbivore carcasses shows similar practices throughout all the layers, primarily involving dismembering the bodies for easier transport, and mostly transporting whole animals to the cave. It is likely that small game was transported in pieces and processed at the site. Based on the assemblage of mammal and mollusc remains, in combination with lithic indicators, it can be concluded that the Vlakno cave exhibits characteristics of a residential camp that was presumably used for the majority of the year, but mainly during autumn, winter, and spring. The zooarchaeological analysis of the mammal and mollusc remains showed that the indicators of a broad-spectrum revolution are visible in Vlakno as well as along the entire eastern Adriatic coast. Although they share certain commonalities, the eastern Adriatic sites have their own microlocation specificities that significantly influenced the adaptation strategies of survival in the area.