Indigenous maize varieties from eastern North America have played an outsized role in breeding programs, yet their early origins are not fully understood. We generated paleogenomic data to reconstruct how maize first reached this region and how it was selected during the process. Genomic ancestry analyses reveal recurrent movements northward from different parts of Mexico, likely culminating in at least two dispersals from the US Southwest across the Great Plains to the Ozarks and beyond.
View Article and Find Full Text PDFTropical freshwater lakes are well known for their high biodiversity, and particularly the East African Great Lakes are renowned for their adaptive radiation of cichlid fishes. While comparative phylogenetic analyses of extant species flocks have revealed patterns and processes of their diversification, little is known about evolutionary trajectories within lineages, the impacts of environmental drivers, or the scope and nature of now-extinct diversity. Time-structured palaeodata from geologically young fossil records, such as fossil counts and particularly ancient DNA (aDNA) data, would help fill this large knowledge gap.
View Article and Find Full Text PDFWe present direct evidence of early grape domestication in southern Italy via a multidisciplinary study of pip assemblage from one site, shedding new light on the spread of viticulture in the western Mediterranean during the Bronze Age. This consist of 55 waterlogged pips from Grotta di Pertosa, a Middle Bronze Age settlement in the south of the Italian peninsula. Direct radiocarbon dating of pips was carried out, confirming the chronological consistency of the samples with their archaeological contexts (ca.
View Article and Find Full Text PDFParallel evolution provides strong evidence of adaptation by natural selection due to local environmental variation. Yet, the chronology, and mode of the process of parallel evolution remains debated. Here, we harness the temporal resolution of paleogenomics to address these long-standing questions, by comparing genomes originating from the mid-Holocene (8610-5626 years before present, BP) to contemporary pairs of coastal-pelagic ecotypes of bottlenose dolphin.
View Article and Find Full Text PDFRecent excavations of Late Antiquity settlements in the Negev Highlands of southern Israel uncovered a society that established commercial-scale viticulture in an arid environment [D. Fuks , , 19780-19791 (2020)]. We applied target-enriched genome-wide sequencing and radiocarbon dating to examine grapevine pips that were excavated at three of these sites.
View Article and Find Full Text PDFHuman populations have been shaped by catastrophes that may have left long-lasting signatures in their genomes. One notable example is the second plague pandemic that entered Europe in ca. 1,347 CE and repeatedly returned for over 300 years, with typical village and town mortality estimated at 10%-40%.
View Article and Find Full Text PDFThe repeated, rapid and often pronounced patterns of evolutionary divergence observed in insular plants, or the 'plant island syndrome', include changes in leaf phenotypes, growth, as well as the acquisition of a perennial lifestyle. Here, we sequence and describe the genome of the critically endangered, Galápagos-endemic species Scalesia atractyloides Arnot., obtaining a chromosome-resolved, 3.
View Article and Find Full Text PDFLeaves of the wild yam species Dioscorea sansibarensis display prominent forerunner or "drip" tips filled with extracellular bacteria of the species Orrella dioscoreae. This species of yam is native to Madagascar and tropical Africa and reproduces mainly asexually through aerial bulbils and underground tubers, which also contain a small population of O. dioscoreae.
View Article and Find Full Text PDFThe Japanese or Honshū wolf was one the most distinct gray wolf subspecies due to its small stature and endemicity to the islands of Honshū, Shikoku, and Kyūshū. Long revered as a guardian of farmers and travellers, it was persecuted from the 17th century following a rabies epidemic, which led to its extinction in the early 20th century. To better understand its evolutionary history, we sequenced the nuclear genome of a 19th century Honshū wolf specimen to an average depth of coverage of 3.
View Article and Find Full Text PDFAdvances in DNA extraction and next-generation sequencing have made a vast number of historical herbarium specimens available for genomic investigation. These specimens contain not only genomic information from the individual plants themselves, but also from associated microorganisms such as bacteria and fungi. These microorganisms may have colonized the living plant (e.
View Article and Find Full Text PDFThe ancient DNA revolution of the past 35 years has driven an explosion in the breadth, nuance, and diversity of questions that are approachable using ancient biomolecules, and plant research has been a constant, indispensable facet of these developments. Using archaeological, paleontological, and herbarium plant tissues, researchers have probed plant domestication and dispersal, plant evolution and ecology, paleoenvironmental composition and dynamics, and other topics across related disciplines. Here, we review the development of the ancient DNA discipline and the role of plant research in its progress and refinement.
View Article and Find Full Text PDFOscillations in the Earth's temperature and the subsequent retreating and advancing of ice-sheets around the polar regions are thought to have played an important role in shaping the distribution and genetic structuring of contemporary high-latitude populations. After the Last Glacial Maximum (LGM), retreating of the ice-sheets would have enabled early colonizers to rapidly occupy suitable niches to the exclusion of other conspecifics, thereby reducing genetic diversity at the leading-edge. Bottlenose dolphins (genus Tursiops) form distinct coastal and pelagic ecotypes, with finer-scale genetic structuring observed within each ecotype.
View Article and Find Full Text PDFThe Eurasian grapevine (Vitis vinifera) has long been important for wine production as well as being a food source. Despite being clonally propagated, modern cultivars exhibit great morphological and genetic diversity, with thousands of varieties described in historic and contemporaneous records. Through historical accounts, some varieties can be traced to the Middle Ages, but the genetic relationships between ancient and modern vines remain unknown.
View Article and Find Full Text PDFAncient plant remains from archaeological sites, paleoenvironmental contexts, and herbaria provide excellent opportunities for interrogating plant genetics over Quaternary timescales using ancient DNA (aDNA)-based analyses. A variety of plant tissues, preserved primarily by desiccation and anaerobic waterlogging, have proven to be viable sources of aDNA. Plant tissues are anatomically and chemically diverse and therefore require optimized DNA extraction approaches.
View Article and Find Full Text PDFIn the 1950s the myxoma virus was released into European rabbit populations in Australia and Europe, decimating populations and resulting in the rapid evolution of resistance. We investigated the genetic basis of resistance by comparing the exomes of rabbits collected before and after the pandemic. We found a strong pattern of parallel evolution, with selection on standing genetic variation favoring the same alleles in Australia, France, and the United Kingdom.
View Article and Find Full Text PDFHere, we report a comprehensive paleogenomic study of archaeological and ethnographic sunflower remains that provides significant new insights into the process of domestication of this important crop. DNA from both ancient and historic contexts yielded high proportions of endogenous DNA, and although archaeological DNA was found to be highly degraded, it still provided sufficient coverage to analyze genetic changes over time. Shotgun sequencing data from specimens from the Eden's Bluff archaeological site in Arkansas yielded organellar DNA sequence from specimens up to 3,100Â years old.
View Article and Find Full Text PDFDomesticated maize evolved from wild teosinte under human influences in Mexico beginning around 9000 years before the present (yr B.P.), traversed Central America by ~7500 yr B.
View Article and Find Full Text PDFIn a new study, previously unknown populations of wild date palm have been identified in remote areas of Oman. Genomic analyses indicate date palm domestication occurred in the eastern portion of the Arabian Peninsula and reveal substantial subsequent gene flow with African palm populations.
View Article and Find Full Text PDFMitochondrial uncoupling protein 1 (UCP1) is essential for nonshivering thermogenesis in brown adipose tissue and is widely accepted to have played a key thermoregulatory role in small-bodied and neonatal placental mammals that enabled the exploitation of cold environments. We map sequences from 133 mammals onto a species tree constructed from a ~51-kb sequence alignment and show that inactivating mutations have occurred in at least 8 of the 18 traditional placental orders, thereby challenging the physiological importance of UCP1 across Placentalia. Selection and timetree analyses further reveal that inactivations temporally correspond with strong secondary reductions in metabolic intensity in xenarthrans and pangolins, or in six other lineages coincided with a ~30 million-year episode of global cooling in the Paleogene that promoted sharp increases in body mass and cladogenesis evident in the fossil record.
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