Intensification of shellfish exploitation: evidence of species-specific deviation from traditional expectations

As modern humans grapple with the repercussions of their extensive environmental impacts, archaeologists are increasingly looking toward the past to understand the nature and extent of prehistoric human impact on the environment. Many researchers rely heavily on archaeological correlates of resource intensification as a proxy measures of resource depletion, a profound and often catastrophic human impact. However, the traditional conceptualization of the archaeological correlates of shellfish intensification disregards a large amount of species-specific variation. This paper presents archaeomalacological data from Santa Cruz Island, California. The shell midden deposits CA-SCRI-480 contain a high density of Tivela stultorum (Pismo clam). Statistical analysis of the shellfish assemblage reveals significant variation in both the size and quantity of Pismo clam that people collected through time. This paper investigates this unique patterning with due consideration of the natural ecology and life history of the species and illustrates species-specific deviation from the traditional archaeological correlates of shellfish intensification. Increased collaboration with ecologists and biologists can help refine models of intensification when necessary in order create more sophisticated understanding of prehistoric human–resource interactions.     

The Broad Spectrum Revolution at 40: Resource diversity,intensification, and an alternative to optimal foraging explanations

More than 40 years ago Kent Flannery coined the term Broad Spectrum Revolution (BSR) in reference to a broadening of the subsistence base of Late Pleistocene hunter–gatherers in the Near East that preceded and helped pave the way for the domestication and plants and animals and the emergence of agriculture. Set within a demographic density model that projected differential rates of population growth and emigration in different resource zones of the Near East, Flannery’s BSR quickly became a global construct linking resource diversification and intensification to imbalances between population and environmental carrying capacity. In recent years the BSR has proven especially attractive to researchers working within an optimal foraging theory (OFT) framework in which diversification and intensification of subsistence only occurs within the context of resource depression, caused by either demographic pressure or environmental deterioration. This OFT perspective, that situates human societies in a one-way adaptive framework as they are forced to adapt to declining availability of optimal resources, however, is increasingly being called into question. Numerous examples of diversification and intensification are being documented in contexts of resource abundance shaped, in part, by deliberate human efforts at ecosystem engineering intended to promote resource productivity. An alternative approach, framed within a newer paradigm from evolutionary biology, niche construction theory (NCT), provides a more powerful explanatory framework for the BSR wherever it occurred.     

The evolution of human culture during the later Pleistocene: Using fauna to test models on the emergence and nature of “modern” human behavior

It has often been argued that the success and spread of modern humans ∼50,000 years ago was due to a series of key behavioral shifts that conferred particular adaptive advantages. And yet, particularly during the African Middle Stone Age (MSA), some of these “modern” behaviors see only patchy expression across time and space. Recent models have proposed a link between the emergence of modern behaviors and environmental degradation and/or demographic stress. Under these models, modern behaviors represent a form of social/economic intensification in response to stress; if this were the case, signs of subsistence intensification should be more common during periods in which these behaviors are manifested than when they are not. In order to test these models, I analyzed faunal remains from Sibudu Cave (South Africa), focusing on the Howieson’s Poort (HP), a phase in which modern behaviors are evidenced, and the post-HP MSA, when classical signatures of such behavior have disappeared. Significant variability in hunting behavior was identified. While much of this variability appears to correspond with changes in the local environment, evidence for resource stress was more common during the HP. The implications of these results to our understanding of the evolution of human culture are discussed.     

ENSO influence on Holocene Aboriginal populations in Queensland, Australia

In the Pacific region, the onset of modern El Niño/Southern Oscillation (ENSO) activity at approximately 5000 years ago may have played a significant role in the development of cultures in the Pacific basin. Within Australia, similar trends in population and resource use have been identified but largely ascribed to cultural changes. To test human responses to changing ENSO activity through the Holocene we analysed a comprehensive suite of 710 radiocarbon ages from archaeological sites in ENSO-sensitive Queensland. We observe a dramatic and sustained increase in landscape activity at inland sites from 4860 ± 15 years ago, statistically indistinguishable from the timing of the onset of modern ENSO activity. Subsequent changes in long-term activity directly impacted on human populations indicating that once established, ENSO maintained a continuous influence on disparate cultures throughout the Pacific basin.     

Focused,intense and long-term: evidence for granular ark (Anadara granosa) exploitation from late Holocene shell mounds of Blue Mud Bay,northern Australia

Explanatory frameworks relating to the appearance of shell mounds and the exploitation of molluscs (particularly the sand/mudflat bivalve Anadara granosa) during the late Holocene have tended to emphasise stasis and continuity. Very few analyses have adequately investigated the intensity of human predation during the mound period and the potential effects on the particular prey species. To this end, the biological and ecological characteristics of A. granosa, the dominant molluscan species for much of the known period of occupation in the region, are considered in detail, in combination with assessing the potential for human impact through predation via the measurement of 9106 A. granosa valves from three shell mounds. In explaining long-term economic change in this region of northern Australia, the focus has been placed on the analysis of relative changes and trends through time in prehistoric resource exploitation.     

Local diversity in settlement,demography and subsistence across the southern Indian Neolithic-Iron Age transition: site growth and abandonment at Sanganakallu-Kupgal

The Southern Indian Neolithic-Iron Age transition demonstrates considerable regional variability in settlement location, density, and size. While researchers have shown that the region around the Tungabhadra and Krishna River basins displays significant subsistence and demographic continuity, and intensification, from the Neolithic into the Iron Age ca. 1200 cal. BC, archaeological and chronometric records in the Sanganakallu region point to hilltop village expansion during the Late Neolithic and ‘Megalithic’ transition period (ca. 1400–1200 cal. BC) prior to apparent abandonment ca. 1200 cal. BC, with little evidence for the introduction of iron technology into the region. We suggest that the difference in these settlement histories is a result of differential access to stable water resources during a period of weakening and fluctuating monsoon across a generally arid landscape. Here, we describe well-dated, integrated chronological, archaeobotanical, archaeozoological and archaeological survey datasets from the Sanganakallu-Kupgal site complex that together demonstrate an intensification of settlement, subsistence and craft production on local hilltops prior to almost complete abandonment ca. 1200 cal. BC. Although the southern Deccan region as a whole may have witnessed demographic increase, as well as subsistence and cultural continuity, at this time, this broader pattern of continuity and resilience is punctuated by local examples of abandonment and mobility driven by an increasing practical and political concern with water.     

Resource intensification in the Late Upper Paleolithic: a view from southern China

Resource intensification is often viewed as a precursor to sedentism and thereby to agriculture. Late Upper Paleolithic sites in China are also seen as important precursors to the beginnings of sedentism and agriculture, but few faunal assemblages have been studied in detail and therefore little is known of pre-Neolithic economies in the region. A large faunal sample from a key site for early pottery and possible rice collection sheds light on subsistence strategies at the end of the Paleolithic. We apply an array of taphonomic analyses to the mammal remains to investigate the extent to which carcasses were processed for within-bone nutrients, which we see as a possible indicator of resource intensification. Determining if this is a regional trend, and/or represents diachronic change in subsistence strategies, will depend on the availability of comparative data in the future.     

Subsistence economics,family size,and the emergence of social complexity in hunter–gatherer systems in eastern North America

A consideration of ethnographic data, computational model results, and archaeological data suggest that changes in family-level economics coincident with subsistence intensification contributed to the emergence of social complexity among prehistoric hunter–gatherers in eastern North America by creating the conditions for a “rich get richer” scenario. Ethnographic data are used to construct a general computational model representing key person- and family-level behaviors, constraints, and decisions affecting the size and composition of hunter–gatherer families. Results from model experiments suggest that lowering the age at which children make a significant contribution to subsistence (e.g., through the broadening of the diet to include the kinds of mass-harvested, “low quality” foods that were increasingly exploited during the Archaic and Woodland periods) relaxes constraints on family size and makes large, polygynous families economically viable. Positive feedbacks between the productive and reproductive potentials of larger families produce right-tailed distributions of family size and “wealth” when the productive age of children is low and polygyny is incentivized. Size data from over 800 prehistoric residential structures suggest right-tailed distributions of family size were present during the Late Archaic through Middle Woodland periods. These distributions would have provided variability in family-based status that permitted the emergence of hereditary social distinctions.     

Prehistoric behavioral depression of cormorant (Phalacrocorax spp.) on the northern California coast

Resource depression is often assumed to result from the over-exploitation of a prey species leading to declines in its population, and therefore availability, to human hunters. However, two other forms of resource depression are noted in the ecological literature: behavioral and micro-habitat depression. Data presented in this paper demonstrate resource depression of cormorants (Phalacrocorax spp.), a coastally breeding and semi-pelagic bird genus, at a coastal site in northern California. Citing modern cormorant behavior and a lack of evidence for intensive rookery exploitation, it is argued that the observed resource depression resulted from changes in cormorant behavior that decreased encounter rates for human hunters. Such behavioral depression is cited as a buffer to the extirpation of prey in mainland settings.     

Implications of a freshwater radiocarbon reservoir correction for the timing of late Holocene settlement of the Elk Hills,Kern County,California

Uncertainties regarding the magnitude of freshwater radiocarbon reservoir effects can introduce random errors into dates on archaeological freshwater carbonates. As a result, many archaeologists avoid dating freshwater shells unless no other datable materials are available. The chronology of prehistoric occupation of the former Naval Petroleum Reserve No. 1 (NPR-1) at Elk Hills, Kern County, has been established with 50 radiocarbon dates on freshwater mussels (Gonidea and Anodonta sp.). Characterization of any freshwater radiocarbon reservoir effect is crucial for the accurate interpretation of inferred settlement and subsistence changes on the Elk Hills. Paired charcoal and freshwater mussels sampled from closely associated contexts were dated to identify a freshwater reservoir effect. Paired Anodonta and Gonidea sp. shells were dated to investigate interspecific differences in fractionation. Results indicate that a 340 ± 20 ¹⁴C yr correction should be applied to conventional ¹⁴C dates on freshwater carbonates in the Buena Vista Basin before calendar calibration. Evidence of interspecific differences is inconclusive. Dates recalibrated with the reservoir correction indicate that widespread occupation of the Elk Hills is correlated with increasing precipitation towards the end of the Medieval Climatic Anomaly and during the Little Ice Age, suggesting that slough resource exploitation may have been driven by regional population pressure rather than drought-related declines in aquatic productivity.     

Late Holocene Changes in Shellfishing Behaviors From the Gulf of Carpentaria,Northern Australia

ABSTRACT

Dramatic changes in shellfishing behaviors occur across northern Australia during the late Holocene, marked most conspicuously by the cessation of large shell mound construction in some areas, and the reorganization of shellfishing behaviors towards more intensive production in the last 1,000 years. Excavations reveal rapid and widespread changes within coastal sites, an increasing diversification in overall subsistence resources, and patterns of increase in site establishment and use. Some of these changes have been argued to be associated with increasing climate variability and a trend towards increasing aridity during the late Holocene, thought to have transformed coastal ecosystems and mollusc availability. However, when these hypotheses are tested at the local level, more nuanced patterns of human-environment interaction emerge, which call into question interpretations based on broad-scale climate records. We suggest that disjunctions in the timing of the cessation of shell mound construction noted between the west and east Gulf of Carpentaria may be related, at least in part, to the timing and intensity of external cultural contacts with Macassan seafarers, associated with reorganization of mobility and production strategies, rather than as yet undemonstrated environmental changes impacting on shellfish availability.     

Investigating shellfish deposition and landscape history at the Natia Beach site,Fiji

The relationship between environmental variation and subsistence practices is a central point of discussion in much Oceanic archaeology. While human predation can significantly reduce prey populations, environmental variation also contributes to reductions in prey abundance, possibly leading to increased human competition and resource scarcity. At the Natia Beach site, Nacula Island, Fiji, geoarchaeological evidence suggests that coastal progradation began soon after initial occupation of the coastal plain. Additionally, at approximately 650 BP a marked increase in clay and silt deposition occurred. Changes in coastal geomorphology may be explained by landscape response to regional Mid-Holocene sea level fall combined with human induced soil erosion due to upland settlement. Smaller scale environmental changes associated with climate variability may have also played a role. Additionally, landscape change appears to have had a measurable impact on local nearshore mollusks that are sensitive to high levels of water turbidity. Minor evidence of human exploitation is observable in this shellfish assemblage, although changes in predation pressure may have allowed shellfish populations to recover. Increased ceramic diversity and fortified settlements also appear at approximately 650 BP on Nacula and other parts of Fiji. The suite of changes at Natia may be explained by processes of regional and local environmental changes, and human adaptation in terms of subsistence, spatial organization, and competition.     

Late Archaic wells on the Gila River Indian Community,Arizona

Eight prehistoric wells dug to a depth of ∼2 m below the modern ground surface were found in the alluvial sediments of McClellan Wash on Gila River Indian Community in southern Arizona. Charcoal from the sediments filling the wells yielded radiocarbon ages of ∼1000 B.C. The time in which wells were dug coincides with a period of general regional aridity and high ENSO activity in the American Southwest. Digging to access water may have occurred in response to period(s) of resource uncertainty, or as a logistical activity that engaged increasingly resource-tethered Late Archaic/Early Agricultural populations. These activities laid the foundation for agricultural practices that eventually became the dominant mode of subsistence in the low-lying areas of the Sonoran Desert.     

Strandloping as a Resource-Gathering Strategy in the Cape,South African Holocene Later Stone Age: The Verloren Vlei Record

ABSTRACT

Elands Bay and adjacent coastline near the mouth of the Verloren vlei on the South African Atlantic coast offered Later Stone Age foragers a variety of marine, estuarine, and terrestrial food resources. We suggest that strandloping (beachwalking or beachcombing) by latest Holocene foragers as a regular practice constituted an important component in their repertoire of subsistence activities. Washed-up mussels, seals, birds, whales, and other recently dead animals would have been available to such strandlopers. We distinguish strandloping as a subsistence practice from the procurement of living prey, including shellfish, mammals, birds, and other animals. The Holocene archaeological record of the Elands Bay area suggests changes through time in resource use, and these changes appear to be recognizable in patterns of shellfish gathering. During the latest part of the Holocene, between about 1,500 and 300 years ago, subsistence practices display a distinctive character that perhaps conforms more strongly than previously to what we conceive of as strandloping.     

Game Resources, Social Interaction, and the Ecological Footprint in Southwest New Mexico

Humans have modified their environments for millennia, but the role of these impacts on economic and social strategies among communities can be difficult to assess. This is due in part to the difficulty of quantifying impacts, which hinders our evaluations of the effects of different resource acquisition strategies and impairs attempts to understand competing demands on resources and their effects on the evolution of social relations. In this paper we employ footprint analysis, a tool used in ecology, to assess the impact of prehistoric subsistence farming communities on the environment, specifically faunal resources. We use footprint analysis to quantify the impact of various strategies of game acquisition by Classic Mimbres period (AD 1000-1130) farmers in the North American Southwest. Assessments are then employed in identifying changes in social relations among communities that may have contributed to settlement changes in the region.     

The social impact of pastoralism in the southwestern Cape

In this paper we suggest that the social and ecological impact of the appearance of domestic animals in the western Cape is visible in a number of different kinds of archaeological observations. Looking at the changes in site distributions through time, at the location of painted sites in relation to other occupied localities, at the kinds of subsistence evidence now accumulating, and at the literature on ritual and stress we see a relatively coherent response emerging. We suggest, as a working hypothesis, that the intrusion of pastoralists increased stress on residual hunter-gatheres and stimulated both ecological and social responses, two of the latter being an intensification of ritual and an increase in painting.     

The First Millennium <Emphasis Type="SmallCaps">bc</Emphasis> in the Highlands of Northern Ethiopia and South–Central Eritrea: A Reassessment of Cultural and Political Development

An overview is offered of the development of research—both archaeological and epigraphic—on the inhabitants of the northern Horn during the first millennium bc. Initially, reconstructions of this period placed considerable emphasis on links with southern Arabia and tended to group those into a single cultural category that was designated ‘Pre-Aksumite’. It is now argued that long-distance contacts were much less pervasive, being largely restricted to the élite, and that other aspects of life—including much material culture and subsistence economy—displayed strong local continuity from earlier times. Similarly, it is argued that interpretation of the epigraphic evidence as indicating a single ‘Pre-Aksumite’ state called D'MT is unjustified.     

Hunter-gatherer cultural dynamics: Long- and short-term trends in Australian prehistory

Recent evidence indicates that a wide range of environmental sectors of Greater Australia had been peopled between ca. 30,000 and ca. 40,000 B.P. Differences in regional Pleistocene patterns of settlement, subsistence, and demography are becoming increasingly evident—such as those between central arid Australia and sub-Antarctic Tasmania. It now remains to model and explain the extremely long-term Pleistocene cultural sequences (spanning tens of thousands of years), in contrast to the more short-term cultural sequences that characterize, for example, the mid-late Holocene period of mainland Australia. While explanations remain unresolved, the latter period indicates the widest range of regional sociocultural and demographic changes.     

Detecting the environmental impact of the Baltic Crusades on a late-medieval (13th–15th century) frontier landscape: palynological analysis from Malbork Castle and hinterland,Northern Poland

Palaeoecological analysis of peat deposits from a small bog, combined with pollen analysis of sediments infilling the moat of the nearby Teutonic Order castle at Malbork, have been used to examine the ecological impact of the Crusades on the late-medieval landscape of Northern Poland. Studies of the environmental impact of the Crusades have been almost exclusively informed by written sources; this study is the first of its type to directly investigate the environmental context of Crusading as a force of ecological transformation on the late-medieval Baltic landscape. The pollen evidence from Malbork Castle and its hinterland demonstrate that the 12th/13th–15th centuries coincide with a marked transformation in vegetation and land-use, characterized by clearance of broadleaved woodland and subsequent agricultural intensification, particularly during the 14th/15th centuries. These changes are ascribed to landscape transformations associated with the Teutonic Order’s control of the landscape from the mid-13th century. Human activity identified in the pollen record prior to this is argued to reflect the activities of Pomeranian settlers in the area. This paper also discusses the broader palaeoecological evidence for medieval landscape change across Northern Poland.     

The Taphonomy of Resource Intensification: Zooarchaeological Implications of Resource Scarcity Among Bofi and Aka Forest Foragers

Zooarchaeological analyses often rely on bone fragmentation, cut marks, and other taphonomic indicators to bolster interpretations of resource intensification that are based on observed changes in prey types and frequencies. While these taphonomic indicators are assumed to be good proxy measures of processing effort, this assumption is based on inadequate actualistic data and analysts often conflate one or more taphonomic indicators as manifestations of the same process. In this paper, we present zooarchaeological data from two villages occupied by Central African forest foragers with very different foraging efficiencies. These data provide the first case where known disparities in diet breadth and foraging efficiency are matched with prey assemblages and taphonomic attributes. Observational and quantitative data show differences between the villages in diet breadth and access to high-ranked prey, but specific taphonomic indicators such as cut mark distribution and intensity do not match predictions generated from models of resource intensification. We propose that linking different taphonomic processes to resource scarcity and intensification can provide powerful adjunctive information. However, because different processing outcomes may be associated with different kinds of resource intensification in response to different kinds of scarcity, we need to strengthen the validity of purported taphonomic indicators with more rigorous independent studies.