Mammuthus columbi

Mammuthus columbi
Name	Mammuthus columbi
Fossil range	Pleistocene–Holocene
Genus	Mammuthus
Species	columbi
Authority	(Cope, 1865)

Mammuthus columbi

Mammuthus columbi was a species of North American proboscidean that lived during the Pleistocene and is a prominent subject in paleontology, paleobiogeography, Quaternary research and Pleistocene megafauna studies. Fossils have informed debates in paleoecology, taphonomy, radiocarbon chronology, and human–megafauna interactions across Ice Age North America, Central America and northern South America.

Taxonomy and nomenclature

Named by Edward Drinker Cope in 1865, the species has been central to discussions among systematists, cladists and molecular paleontologists working with Charles Darwin-era comparative morphology, Neogene proboscidean revisions and ancient DNA studies. Debates involve comparisons with Eurasian species described by Georg Wagler, Georg August Goldfuss and later revisions by Henry Fairfield Osborn, with phylogenetic placement reevaluated using methods developed by researchers at institutions such as the Smithsonian Institution, the American Museum of Natural History and the Natural History Museum, London. Collation of osteological, dental and mitochondrial datasets has implicated gene flow, hybridization and possible introgression in relationships to species described from Siberia and Eurasia by teams including those at University of Copenhagen, Max Planck Society and Harvard University.

Description and anatomy

Skeletal reconstructions from collections at the Los Angeles County Museum of Natural History, the Field Museum, and the Royal Ontario Museum reveal large body size, columnar limbs and hypsodont molars adapted for grazing studies paralleling comparative anatomy research performed at Yale University, University of Michigan and University of California, Berkeley. Dentition analyses referencing works by Gideon Mantell and modern dental microwear paleontologists show lamellar enamel plates and enamel thickness data similar to Eurasian counterparts described by Othniel Charles Marsh and modern researchers at University of Oxford and University of Copenhagen. Musculoskeletal inferences draw on analogies with extant African elephant studies from the Kenya Wildlife Service and Smithsonian Tropical Research Institute and functional analyses from biomechanics labs at Massachusetts Institute of Technology and University of Cambridge.

Distribution and habitat

Fossil localities span from Alaska and Yukon sites documented by researchers at the University of Alaska Fairbanks to sites in Florida, Texas, Kansas, California, Oregon, Arizona, New Mexico, Nevada and into Central America and Colombia, with records curated by museums including the Florida Museum of Natural History, the San Diego Natural History Museum, and the Royal Tyrrell Museum. Paleoenvironmental reconstructions using palynology and stable isotope analyses conducted at laboratories such as Lamont–Doherty Earth Observatory, University of Arizona, and the University of Minnesota indicate occupation of grassland, savanna, parkland and riparian mosaics contemporaneous with glacial–interglacial cycles studied in cores from Greenland, Antarctica and the Great Lakes. Biogeographic syntheses link range shifts to corridors like the Great Plains and refugia discussed in Quaternary research at University of Washington and University of Toronto.

Behavior and ecology

Isotopic ecology and microwear studies by teams at University of California, Los Angeles, Pennsylvania State University, and University of Colorado suggest a predominantly grazing diet with seasonal browsing, analogous to behavioral models developed for elephantid research at the Zoological Society of London and the Wildlife Conservation Society. Social structure inferences draw on mortality profiles from mass-death assemblages excavated by crews affiliated with the University of Utah, the University of Nebraska–Lincoln and the University of Kansas, paralleling herd dynamics studied by field biologists at the Ngorongoro Conservation Area Authority and researchers associated with Conservation International. Reproductive biology, growth patterns and ontogenetic studies have been informed by histology labs at University of California, Davis and developmental work paralleled in primate and mammal life-history research at Max Planck Institute for Evolutionary Anthropology and Columbia University.

Paleoecology and interactions with humans

Sites such as those investigated by archaeologists from University of Arizona, Texas A&M University, University of Colorado Boulder and the Smithsonian Institution contain kill-site interpretations, but debate continues over taphonomy, stratigraphic integrity and association with lithic industries like those studied at Clovis sites by teams from University of Pennsylvania, Crow Canyon Archaeological Center and the Museum of Natural History, New York. Radiocarbon chronologies produced by University of Oxford and Lawrence Berkeley National Laboratory and lithic analyses referencing work at Paleoindian Research centers link possible human exploitation to prehistoric cultures described at Monte Verde, Blackwater Draw, Gault Site and other landmark localities. The species figures in models of human foraging, megafaunal hunting and Pleistocene extinctions debated at symposia of the Society of Vertebrate Paleontology, the Paleoanthropology Society and conferences hosted by National Geographic Society.

Extinction and chronology

Chronological frameworks from accelerator mass spectrometry facilities at Australian National University, Arizona State University and University of Arizona place last occurrences variably across regions, tying extinction intervals to climatic transitions recorded by ice-core and sedimentary archives at Vostok Station, EPICA and lake records from Lake Baikal and the Great Salt Lake. Multicausal explanations involve climate shifts, habitat change, human impacts and ecological cascades explored by teams at University College London, Australian National University and the Max Planck Institute for the Science of Human History, with debates reflected in syntheses by the National Academy of Sciences, the Royal Society and international paleontology congresses. Ongoing ancient DNA, proteomics and geochronology studies at institutions such as University of Copenhagen, McMaster University and University of Adelaide continue refining the timing and causes of disappearance.

Category:Pleistocene proboscideans Category:Quaternary mammals of North America