مقاله انگلیسی رایگان در مورد تکامل روش ها و افکار در مطالعات انجماد غلات – الزویر 2017

Cereals have a long history of interaction with humans. At around 40–50 thousand years ago (kA), late Neanderthals consumed wild Triticeae grains in a cooked form as suggested by the analysis of the dental calculus from multiple locations in Europe, the Near East, and Africa [1]. The first fossil remnants of plants exhibiting characteristics of the domesticated cereal crops have been discovered at the multiple archaeological sites dated to 8–10 kA — the historic period marking a transition from the huntergatherer lifestyle to the early sedentary agricultural societies. The most prominent examples are the non-brittle spikes of the proto-domesticated wheat (diploid, tetraploid and hexaploid Triticum species) and barley (Hordeum vulgare ssp. vulgare) discovered in the excavations in the Fertile Crescent area of the Near East; the nonshattering panicles of rice (Oryza sativa) from the Yangtze river valley, China; and the starchy enlarged seeds of maize (Zea mays ssp. mays) from the Central Balsas river valley, Mexico, which distinguish maize from its wild progenitor teosinte (Z. mays ssp. parviglumis) [2– 6]. The archaeobotanical analyses of the fossil findings provided direct empirical evidence on the temporal scale and the location of the early events of cereal domestication history, which was packaged in the so-called domestication models [2,3,7]. However, to expand on the archaeological models, detailed understanding of genetic relationships between the cultivated and wild populations is crucial. In the pre-genomics era, the pioneering molecular studies suggested explicit demographic models of cereal domestication based on the population genetic analyses of nucleotide variation in isolated genes and genomic regions [8–12]. The molecular evolutionary models favored a monophyletic origin of crops and strong selective pressures under domestication. On the contrary, the archaeological models assumed a polycentric origin of domestication traits and a millennia-long process of fixation of these traits in the cultivated populations. Advancements in the genome sequencing technologies enabled the elucidation of the genetic ancestry and evolutionary history of domesticated genotypes at the unprecedented resolution and scale [13,14 ,15]. It was anticipated that the genome-wide diversity estimates would provide a solid basis to the demographic history reconstruction. However, for many cereals, the interpretation of the revealed patterns remained controversial hinting at the complexity of their evolutionary history [15,16 ]. Population genomics has recently revealed intriguing patterns in the cultivated barley genomes that shed light on the trajectory of barley domestication [17,18,19].