## 1 Introduction  
An evolutionary history of _Saccharomyces_ wine yeasts includes spontaneous and naturally occurring events, such as heterozygosity, nucleotide and structural variations, introgressions, horizontal gene transfers, and hybridization, as well as human-enforced domestication effects [1; 2; 3; 4]. Interestingly, this 7000-year-long history of tight interrelationships between yeast, humans, and human-related environments has resulted in the occurrence of genetic variants within some _Saccharomyces cerevisiae_ lineages that are unique to several subpopulations (i.e., Japanese sake strains). The history of the domesticated _Saccharomyces_ breeds is mainly linked to fermentation processes; hence, there is a history of the evolution of wine yeast toward coping strategies that address fermentation-relatedchallenges [1]. This in turn has led to genetic divergence between wine and non-wine _Saccharomyces_ strains [2]. Indeed, wine yeast cells are subjected to a variety of stresses during winemaking processes, such as high osmolarity, high sulfite dosages, nutrient depletion, acid stress, anaerbiosis, as well as a constantly increasing concentration of ethanol. The latter in turn exerts high chaotropic activity [5], reduces water activity [6] resulting in ethanol-induced water stress [7], and can negatively affect macromolecular systems [5]. However, as aforementioned, yeasts have been employed for wine production for thousands of years; therefore, they have evolved adaptive functions that enable them to fit in a fluctuating wine fermentation environment [1; 2; 3; 8]. Such adaptations can be conferred by nucleotide changes, including base insertions, deletions, or substitutions, and/or by structural genome rearrangements on a large scale, such as chromosome duplications and translocations. These modifications can result in small-scale alterations in gene expression, protein structures, and protein interactions, or large-scale changes in genomic contexts or copy number variations [1; 2; 3; 4]. Because of its extremely phenotypic plasticity and intra-specific variability, _S. cerevisiae_ exhibits high competitive abilities, manifesting in its dominance within microbial communities in both spontaneous and inoculated fermions [1; 8]. Collectively, these features resemble the characteristics and behavior of plant weeds [8]. The adaptability and competitive ability of _S. cerevisiae_ underlie in turn an adaptive evolutionary-based approach, which is used by many researchers to develop industrial microorganisms with novel characteristics. In general, adaptive laboratory evolution (ALE) [9; 10; 11; 12] is an approach based on the long-term adaptations of yeasts (and other organisms) to environmental and/or metabolic regimes. It is becoming an important alternative to strategies that utilize recombinant DNA technologies to develop economically important microorganisms [1; 2; 12]. Although genetic and/or genome engineering is nowadays more precise and has become a promising approach to develop wine yeast strains [1; 2; 12], consumers often do not accept the use of recombinant DNA technologies in food products [1; 2; 13; 14]. The biotechnological usefulness of ALE strategy has been confirmed by several researchers to date, who employed the ALE approach to obtain thermotolerant [11], copper-tolerant [15], or saline-tolerant [16] yeast strains. In turn, the use of KCl-ALE (adaptive laboratory evolution under KCl-induced osmotic stress conditions) has been documented by [PERSON] et al. [10], who successfully combined it with breeding approaches to remodel wine yeast strain metabolisms toward decreased ethanol production and enhanced glycerol biosynthesis [10]. The latter is thought to provide better sensorial of wine quality by improving its organoleptic properties, such as beverage body and fullness [17], as well as serves as a key osmoprotectant that preserves cells from the harmful effects of osmotic stress [18; 19]. Besides, glycerol acts as a compatible solution that counteracts the negative effects of ethanol.