University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Nebraska Anthropologist Anthropology, Department of 1995 PALEOECOLOGICAL IMPLICATIONS OF PLANT/ANIMAL GRAZING RELATIONS ON THE MAMMOTH STEPPE OF EASTERN BERINGIA Andre Antinori Follow this and additional works at: https://digitalcommons.unl.edu/nebanthro Part of the Anthropology Commons Antinori, Andre, "PALEOECOLOGICAL IMPLICATIONS OF PLANT/ANIMAL GRAZING RELATIONS ON THE MAMMOTH STEPPE OF EASTERN BERINGIA" (1995). Nebraska Anthropologist. 79. https://digitalcommons.unl.edu/nebanthro/79 This Article is brought to you for free and open access by the Anthropology, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Nebraska Anthropologist by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. PALEOECOLOGICAL IMPLICATIONS OF PLANT/ANIMAL GRAZING RELATIONS ON THE MAMMOTH STEPPE OF EASTERN BERINGIA Andre Antinori This paper reassesses the areal extent of Mammoth Steppe in Eastern Beringia and discusses some of the ways in which grazing and topography entered into the maintenance of the Mammoth Steppe. Large, generalist grazing mammals, by their grazing style, helped maintain the Mammoth Steppe by removing old-growth and by stimulating grass plants to reproduce vegetatively. These grazers also' promoted uniformity in growth-form and uniformity in plant biomass (phytomass) above and below the ground surface. During the late Pleistocene the58 large, generalist grazers were eliminated from interior Alaska by Paleolndian hunters and their predatory animal companions. The loss of these large, generalist grazers precipitated a change in the structure of the Mammoth Steppe grassland and this eventually led to the replacement of steppe grassland by herb tundra. were not human habitat there would be Broadcast little reason for geographers or anthropologists to study it. burning by humans and naturally­ This paper is an attempt to occurring fire are two reasons classically describe the full-glacial vegetation of given for the formation and maintenance interior Alaska/Yukon and to explain the of grasslands. Grazing is another. This role of grazing and topography in the paper explores grazing in a human maintenance of Mammoth Steppe. The habitat. Habitat, nature and natural understanding of grazing relationships resource are categories that are defined not only benefits anthropologists and by people rather than objects defined by geographers who focus their attention on their own intrinsic qualities. Without humans in grassland settings but is also human definition habitats are no more of value to the archaeologist who deals than systems among systems within a with hunting and pastoral peoples before universe of systems. Mammoth Steppe and after the advent of livestock raiSing. was human habitat in Siberia before the Hopefully this paper will put human action human occupation of eastern Beringia in perspective by casting people as a (Powers 1973). It remained human proximate rather than the ultimate cause habitat until its disappearance from the of environmental change and provide Beringian landscape. If Mammoth Steppe Andre Antlnorl, Geography, University of Nebraska-Lincoln 68588 The Nebraska Anthropologist Vol. 12, No.1, 1995-1996, pp. 75-88 75 Antinori TtE NEBRASKA ANlHROPOLOGIST another way of looking at human impact diversity of opinions have arisen about on grassland ecosystems. the nature of the Beringian landscape during the last full-glaciation (about Paleolndlans In Beringia 35,000 to 16,000 yrs BP). Consequently many of the Humans may have entered North scenarios, theories and models used to America as early as 50,000 years before describe and explain the past vegetation the present (yrs BP) as part of the of Beringia are highly speculative and do Siberian faunal assemblage that crossed not necessarily represent observable, the Bering Land Bridge (Fig. 1) during demonstrable facts nor even accepted that time (Kurten and Anderson 1980; opinions. Turner 1984). However this date is purely speculative. Actual dated material from Vegetation in Beringia Bluefish Caves in the Yukon place humans in eastern Beringia around Two major vegetation types (herb 24,800 yrs BP well within the time-frame tundra and grassland steppe) probably dealt with by this paper. At Bluefish existed in interior Alaska during the Caves Morlan concluded: period of the last glaciation. Boreal forest tree species were confined to isolated Human presence is inferred from a variety of flaked -refugia to the southwest (Hopkins 1972) stone tools, including burins, microblades, and a and east (Anderson 1985, 1988). The microcore, several kinds of bone tools, numerous butchering marks on bones, bone breakage general look of the summer landscape patterns, and selective representation of was green and treeless with shrubby anatomical parts (Morlan 1987:38) willows in situations favorable to their growth. A number of smaller The human artifacts were found in environments were found within the two association with thousands of well­ major vegetation types such as the sand preserved bones of local ice-age dunes and shallow fresh-water marshes, mammals. Prior to this time humans in ponds and bogs of the exposed Chukchi eastern Beringia may have chosen to use Sea shelf (Elias et aI. 1992). Familiar tools of expedience such as splintered Alaskan boreal forest tree species of animal bones. Tools of this type would today (spruce and fir) did not re-invade have left little or no artifactual record. interior Alaska and the Yukon until sometime during the most recent Paleoenvironmental Interpretation deglaciation (13,000 to 11,500 yrs BP) (Ritchie 1984). By its very nature fossil pollen data is usually biased toward woody species, exotic pollen influx and local taxa that either produce an overabundance of pollen or are locally abundant at the depositional site. As a result of this bias a 76 VOL. 12, NO.1, 1995-1996 PALEOLOGICAL IMPLICATIONS Figure 1. The BerIng Land Bridge showing western (Asiatic) and eastern (American) BerIngia Herb Tundra time eastern Hokkaido (today's northern island of Japan) and the exposed During the last full-glacial, the northwestern Pacific shelf was a refugium vegetation of northwestern Canada has for boreal forest and tundrattundra been reconstructed by Ritchie and parkland species. The climate there was Cwynar as sparse, discontinuous herb cold and wet (Heusser and Mortey 1985). tundra in uplands and continuous grass­ From 16,000 to 12,000 yrs BP herb sedge marshes with local willow thickets tundra gave way to willow tundra and in lowlands (Cwynar and Ritchie 1980; scattered dwarf birch. This vegetation Cwynar 1982; Ritchie 1984). The climate type dominated upland sites until about was cold and dry analogous to the 11,500 yrs BP. The modem analog modem-day mid-arctic climate of the climate for this vegetation are the northern portions of Banks and Victoria southern portions of Banks and Victoria Islands (July mean 2-6 degrees C) Islands where the July mean is 10-13 (Ritchie 1984). At approximately the same degrees C (Ritchie 1984). Dwarf birch, a 77 THE NEBRASKA ANlHROPOLOGIST familiar tundra shrub, spread across findings and her own field work, Anderson northcentral and northwestern Alaska later concluded that the vegetation of her during this period, However it was not fossil pollen sites was "perhaps more common in the region until 12,000 yrs BP similar" to mid-arctic tundra than to arctic or later (Anderson 1988). meadows (Anderson 1988:270). Both of Herb tundra (Fig. 2) occurred these interpretations are probably correct throughout eastern Beringia below the and her characterization of the herb zone mountain glaciers of the Brooks Range, as "a complex mosaic of tundra types with Alaska Range and Richardson Mountains no latitudinal or longitudinal pattern" and between these mountain ranges and seems reasonable (Anderson 1985:271). the grasslands of the Mammoth Steppe. According to Barnosky and associates Smaller Environments this vegetation was a drier tundra in northeastern Alaska and northwestern In the central Brooks Range, Canada and a wetter (more mesic) tundra Brubaker and associates found that both in northwestern Alaska (Barnosky et al. sparse, discontinuous herb tundra and 1987). The fossil pollen sites used to map meadow plant communities existed this vegetation type are Scattered simultaneously. She' proposed " ... that throughout interior Alaska and the Yukon both vegetation types existed under the (Barnosky et aI. 1987). same regional climate, depending on The predominant taxa of the herb local soil-drainage conditions" (Brubaker tundra zone were various species of et al. 1983:206), thus lending support to sedge, grass, sage (Artemisia) and willow the mosaic-crafters of Alaskan and (Salix). The genus and species of Yukonan paleoecology such as Young individual grasses and sedges cannot be (1982). resolved by fossil pollen analysis. The The role of soil (edaphic) and presence of sage in this vegetation belt microclimatic factors of the environment may be alternatively interpreted as dry, to the success or failure of plants is well rocky upland habitats, river banks, known to geographers and ecologists. meadowy terraces or even areas of Climatic regimes vary over several levels disturbance (Cwynar 1982; Anderson of spatial resolution and soil varies in 1988; Paus 1988). "In neither the upland both structure and texture within relatively nor lowland setting, however," says small