title: Genomic Data from Extinct North American Camelops Revise Camel Evolutionary History.
abstract: Recent advances in paleogenomic technologies have enabled an increasingly detailed understanding of the evolutionary relationships of now-extinct mammalian taxa. However, a number of enigmatic Quaternary species have never been characterized with molecular data, often because available fossils are rare or are found in environments that are not optimal for DNA preservation. Here, we analyze paleogenomic data extracted from bones attributed to the late Pleistocene western camel, Camelops cf. hesternus, a species that was distributed across central and western North America until its extinction approximately 13,000 years ago. Despite a modal sequence length of only around 35 base pairs, we reconstructed high-coverage complete mitochondrial genomes and low-coverage partial nuclear genomes for each specimen. We find that Camelops is sister to African and Asian bactrian and dromedary camels, to the exclusion of South American camelids (llamas, guanacos, alpacas, and vicuñas). These results contradict previous morphology-based phylogenetic models for Camelops, which suggest instead a closer relationship between Camelops and the South American camelids. The molecular data imply a Late Miocene divergence of the Camelops clade from lineages that separately gave rise to the extant camels of Eurasia. Our results demonstrate the increasing capacity of modern paleogenomic methods to resolve evolutionary relationships among distantly related lineages.
authors.affiliation: Department of Ecology & Evolutionary Biology, University of California Santa Cruz peteheintzman@gmail.com.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Heintzman
authors.affiliation: Yukon Palaeontology Program, Department of Tourism & Culture, Government of Yukon, Whitehorse, YT, Canada.
authors.forename: Grant D
authors.initials: GD
authors.lastname: Zazula
authors.affiliation: Department of Ecology & Evolutionary Biology, University of California Santa Cruz.
authors.forename: James A
authors.initials: JA
authors.lastname: Cahill
authors.affiliation: Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Alberto V
authors.initials: AV
authors.lastname: Reyes
authors.affiliation: Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY.
authors.forename: Ross D E
authors.initials: RD
authors.lastname: MacPhee
authors.affiliation: Department of Ecology & Evolutionary Biology, University of California Santa Cruz UCSC Genomics Institute, University of California Santa Cruz.
authors.forename: Beth
authors.initials: B
authors.lastname: Shapiro
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D002162:Camelus / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D053476:Extinction, Biological; D005580:Fossils; D049810:Genetic Speciation; D054629:Genome, Mitochondrial; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009656:North America; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial
keywords: Camelops; Pleistocene; arctic; camel evolution; morphology; paleogenomics; phylogeny