Beringian Refugium Research Articles

Transberingian dispersal of cestodes in mammals

During Pleistocene glaciations, eustatic lowering of sea-level exposed the continental shelf between northeastern Eurasia and northwestern North America. That land in combination with unglaciated areas on the adjacent continents formed a vast region open to the west but bounded on the east by continental ice. Organisms from Eurasia spread into the unglaciated Beringian refugium, which was biotically an eastward extension of the Palaearctic. With rising sea-levels following glacial periods, the Bering Strait was formed and organisms of Eurasian origin were left within the nearctic sector of Beringia. As the continental ice disappeared, plants and animals spread eastward and southward from Beringia, while organisms from beyond the southern margins of the ice extended their ranges northward. The significance of Beringia is discussed with reference to the dispersal of host-specific cestodes in mammals that attained holarctic status during the late Pleistocene.

GEOGRAPHIC DISTRIBUTION AND BIOGEOGRAPHY OF REPRESENTATIVE SPECIES OF XERIC GRASSLAND-ADAPTED NEARCTIC LYGAEIDAE IN WESTERN NORTH AMERICA (INSECTA: HETEROPTERA)

AbstractThis paper outlines the known distribution of eight xeric grassland-adapted species of Lygaeidae, and examines these distributions with respect to the glacial history of North America during the Pleistocene, and past and present distribution of grassland vegetation. Four of these species (Neosuris castanea,Sisamnes claviger,Ligyrocoris latimarginatus, andMelanopleurus perplexus) probably survived the Pleistocene in refugia south of the Late Wisconsinan ice sheet. Differences in climatic requirements may explain the variations in geographic distribution exhibited by these four insects and a methodology for testing this is discussed. The four other species (Crophius ramosus,Kolenetrus plenus,Slaterobius insignis, andEmblethis vicarius) may have occurred in the north prior to 1.2 mya and survived the Late Pleistocene in both the northern Beringian refugium and in southern refugia. Molecular systematics, especially use of DNA restriction site or sequence data, might provide the evidence needed to test historical biogeographic postulates based on the extant distribution of these species.

Paleoecological Significance of Holocene Insect Fossil Assemblages from the North Coast of Alaska

Two peat sections containing insect fossil remains from the eastern coastal plain of the Alaskan North Slope were analyzed in comparison with pollen studies. The sections span a period from 10,400 B.P. to 1,320 B.P., providing information on the post-glacial distributions of some of the beetles species that were a part of the Beringian refugium fauna. The fossil insect evidence suggests climatic conditions similar to modern parameters, especially in the early Holocene, in general agreement with paleobotanical and vertebrate fossil interpretations for the coastal plain and elsewhere in eastern Beringia. Key words: Holocene, paleoenvironments, insect fossils, Alaska

: Folsom Tools and Technology at the Hanson Site, Wyoming . George C. Frison, Bruce A. Bradley. ; A Report on the Banting and Hussey Sites. Two Paleo-Indian Campsites in Simcoe County, Southern Ontario . P. L. Storck. ; Pleistocene Bone Technology in the Beringian Refugium . Robson Bonnichsen. ; Early Man in America from a Circum-Pacific Perspective . Alan

American AnthropologistVolume 84, Issue 2 p. 447-449 Free Access Archeology: Folsom Tools and Technology at the Hanson Site, Wyoming, George C. Frison and Bruce A. Bradley.: A Report on the Banting and Hussey Sites. Two Paleo-Indian Campsites in Simcoe County, Southern Ontario. P. L. Storck.: Pleistocene Bone Technology in the Beringian Refugium. Robson Bonnichsen.: Early Man in America From a Circum-Pacific Perspective. Alan Lyle Bryan, ed Dennis Stanford, Dennis Stanford Smithsonian InstitutionSearch for more papers by this author Dennis Stanford, Dennis Stanford Smithsonian InstitutionSearch for more papers by this author First published: June 1982 https://doi.org/10.1525/aa.1982.84.2.02a00400AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume84, Issue2June 1982Pages 447-449 RelatedInformation

A Major Range Extension for Encalypta longicolla

Encalypta longicolla Bruch is reported from western Newfound- land. This is the first report of this species from eastern North America, disjunct by 6500 km from the nearest populations in Alberta. We have recently collected Etcalypta longicolla Bruch in western Newfoundland. The determination was based on the very large, coarsely papillose spores measuring 50-55(60) p/m (see Horton 1979), the small gametophyte, and the distinctive purple-red peristome, which is large in comparison to the size of the capsule. The specimens are from Tuckers Head, Bonne Bay, 49027'N, 57'46'W (Belland 2863, Brassard 13132-NFLD) and represent the first record for eastern North America. By comparison with the distributional map of E. longicolla for North America published by Horton (1979), the Newfoundland population is very disjunct, being approximately 6500 km from the nearest stations in western Canada. Tuckers Head is an exposed, NW-facing limestone headland composed of numerous small cliff sections separated by talus slopes. Although the cliff faces appear xeric, nu- merous seepages occur on them. In addition, low cloud and fog often surround the cliffs and provide a frequent source of moisture. Encalypta longicolla was found on a limestone cliff at approximately 100 m altitude. The habitat of the Newfoundland population is similar to those of the northwestern North American populations described by Horton (1979). The world distribution of Encalypta longicolla was summarized by Steere (1978) as follows: A rare arctic-alpine species which in North America extends from Alaska and the Yukon southward in the Rocky Mountains to northern British Columbia. Rare also in the Alps, from which it was first described; arctic Asiatic USSR. Crum (1963) suggested that, in its Rocky Mountain range, Encalypta longicolla may have survived the vicissitudes of the Pleistocene in situ, whereas Horton (1979) stated that its distribution in northwestern North America probably reflects limited dispersal of E. longicolla from Beringian refugia since the Wisconsin glaciation. Against the back- ground of recent geological evidence for the presence of ice-free areas in western New- foundland during the Wisconsin Glaciation (Grant 1977), it is also possible that E. longi- colla survived this period in Newfoundland. Financial support for this study was provided by the Natural Sciences and Engineering Research Council of Canada (Grant A-6683 to the second author). We thank Dr. Howard Crum for verifying our determination, Parks Canada for permission to collect in Gros Morne National Park, and Dr. W. S. G. Maass for comments on the manuscript. Crum, H. 1963. Encalypta brevicolla and E. longicolla in North America. Nat. Mus. Canad. Bull. 186: 36-44. Grant, D. R. 1977. Altitudinal weathering zones and glacial limits in western Newfoundland, with particular reference to Gros Morne National Park. Geol. Surv. Canad. Paper 77-1A: 455-463. Horton, D. G. 1979. Encalyptaceae Americanae Exciccatae: An annotated guide to Fasciculus I

Chromosomes of the siberian snow sheep, Ovis nivicola, and implications concerning the origin of amphiberingian wild sheep (subgenus Pachyceros)

The chromosomes of Ovis nivicola, described for the first time, exhibit 2 n = 52, the lowest diploid number to be reported for wild sheep and goats. The new chromosomal data, together with a review of the fossil history of the genus, lead us to conclude that the bighorned wild sheep (subgenus Pachyceros) evolved their distinctive characteristics while isolated in the ice-free Beringian refugium, and then migrated southward into western North America when the glacial barriers melted, as first suggested by Cowan (1940).

Upper Pleistocene Radiocarbon-Dated Artefacts from the Northern Yukon

The evidence presented here indicates that man lived in the eastern part of the Beringian refugium before the peak of the late Wisconsin glaciation (27). He had sharp, stone tools intended for working bone and means of breaking large mammoth bones. Probably he hunted mammoth and caribou, and prepared the skins of the caribou for use as clothing and perhaps shelter. It is possible that he migrated to southern North America, although evidence for the presence of man there prior to the peak of the Wisconsin glaciation is at present in dispute (28). We do not know whether his culture should be classified as Mousteroid or Aurignacoid in Müller-Beck's scheme (23), whose criteria are taken from stone implements of which we have none, although we infer their presence. Our data suggest that in Beringia, and therefore probably in Siberia and the Far East, the transition from Middle Paleolithic to Upper Paleolithic levels of technology occurred at a relatively early date. This raises the larger question: Did the transition from Middle to Upper Paleolithic occur simultaneously in many parts of the world, or did it begin in and spread from one area (23)?

Paleoecology of a Late Pleistocene Small Mammal Community from Interior Alaska

The material was recovered from exposures, mostly mine cuts through the silt, to reach auriferous gravels at five localities near Fairbanks. The age range of the silts is mainly early Illinoian - present. The vole Microtus gregalis predominates in the fossil assemblage, indicating a habitat above tree line with welldrained soils. M. gregalis, Citellus undulatus and Dicrostonyx torquatus are not now found in the area however, and their extinction is attributed to a rapid reduction of a preferred habitat at the end of the Wisconsin glaciation. Evidence from large mammalian fossils indicates that tree line was lowered at least 300 m during the Wisconsin phase and that most of the mammals were grazers. This supports the small mammalian indications that welldrained alpine meadow expanded almost down to the river flats in interior Alaska during the last two glaciations. The distribution changes and extinction of the small mammals are discussed in relation to the intercontinental communities and interchanges within the Beringian refugium in eastern Siberia and Alaska.