Vertebrate paleontology and the alleged ice-free corridor: The meat of the matter

The existence of a full-glacial, ice-free corridor through western Alberta has been argued for many years. It has been assumed to have existed, notwithstanding a near total lack of evidence, by many in the North American archeological community as a means of explaining the occurrence of 'early man' south of the ice in early postglacial time. In the last 15 years, much has been done to fill the knowledge gap (including theories on alternate routes) but there is still no consensus. Quaternary vertebrate fossils from Alberta, accompanied by numerous radiocarbon dates with a clear gap between 21 ka BP and at least 11.6 ka BP, now suggest that Alberta was overridden by ice during an extensive Late Wisconsinan glaciation. Therefore, a full-glacial, ice-free corridor could not have existed. However, much of the province could have served as a migration route, northward and southward, both before and after Late Wisconsinan glaciation. The preglacial passage could not have been a 'corridor' because numerous megafaunal remains and conifer wood, from numerous localities, with finite dates from ca. 43 ka to 21 ka BP, indicate extensive, ice-free conditions. Similarly, a Late Pleistocene corridor-critically appraised from the standpoints of vertebrate paleontology and archeology - is irrelevant because, by the time human migrants arrived in southern Alberta, less than 11 ka BP, the ice had been in retreat for well over 1000 years. Relative to human influx, the continuing use of the term 'corridor', with its connotation of a narrow or restricted passage, seems inappropriate. Copyright (C) 1996 INQUA/Elsevier Science Ltd