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Reconstructing the dynamics of ancient human populations from radiocarbon dates: 10 000 years of population growth in Australia
Proceedings of the Royal Society B
Abstract
Cited By (since 1996):7, Export Date: 26 November 2013, Source: Scopus
... (iv) human use of refugia, particularly during the Last Glacial Maximum (LGM) and (v) demography and sea-level change during the most recent transgression (Table 1, 3.3.1 | Late Holocene population growth, expansion and increased cultural complexity (key papers: ; see also C. N. Johnson & Brook, 2011) The issue ...
... On the basis of continental-scale studies of radiocarbon age determinations, the Late Holocene in Australia has been viewed as a period of demographic expansion and growth, greater sedentism and increased social and technological complexity (C. N. Johnson & Brook, 2011;Williams et al., 2013). Such views have not gone unquestioned (Attenbrow, 2006;Davies & Holdaway, 2017;Morgan, 2015;Vaesen et al., 2016). ...
Statistical manipulation of large radiometric data sets (big data) is increasingly applied to those grand challenges in archaeology that relate to past human‐behavioural dynamics and includes frequency analysis of radiocarbon ages (summed probability distributions [SPDs]). Australian SPD studies use the radiocarbon database “AustArch” to examine regional‐ and continental‐scale demographic change. We review Australian studies, focussing on sampling bias and taphonomic bias, finding that (i) time‐averaged radiometric data cannot simply be correlated across regions, and (ii) sedimentology imposes genuine constraints upon what can be known. Internationally, flaws in SPD use occur in all main research phases, and most importantly, at the initial phase of defining research questions, logic and general approach. Major problems stem from not planning to obtain a sound understanding of the variability of past sedimentary environments, potential occupation sites and site formation processes. Thus, cultural inferences are too often made from archaeological data without due consideration of the natural processes that may explain the data. Highlighting exemplar studies, we present practical approaches to improve SPD use for exploring changes in demography, aimed at reducing uncertainties and reconnecting archaeological, chronological, geological and sedimentary data. Most important is to increase understanding of physical processes and their control on the archaeological record.
... En general la SCDPD ibérica presenta numerosos dientes de sierra, más de lo esperable si reflejara el po- blamiento: aunque hay autores que toman estas situa- ciones como resultado de factores poblacionales deri- vados de cambios climáticos o subsistenciales (Johnson y Brook, 2011;Robinson et al., 2013;Zahid et al., 2015), la realidad es que también actúan la oportunidad de los datos, la reconversión de la edad isotópica a calendári- ca y los cambios en las estrategias poblacionales. ...
... Si las SCDPD reflejaran la dinámica del poblamien- to teóricamente estaríamos en condiciones de calcular la tasa anual de crecimiento demográfico (Johnson y Brook, 2011;Riede, 2009;Shennan et al., 2013;Tallavaara et al., 2015;Collard et al., 2010;Downey et al., 2014;Hinz et al., 2012;Porčić et al., 2016) para compa- rarla con la esperada capacidad reproductiva de socie- dades no jerarquizadas. Sin embargo, un crecimiento de población no generará nuevos yacimientos hasta Fig. 5. SCDPD Regionales. ...
... Being comprised of artifacts and features combined Benjamin Davies and Simon J. Holdaway on a common surface, the primary mechanism by which archaeologists establish chronology, vertical stratigraphy, cannot be used as typically conceived (Harris 1979). The inability to order surface deposits within a stratigraphic sequence leads to concerns over biases in temporal relationships within and between surface deposits (e.g., Clarkson 2008, 493), concerns that are sometimes used to justify a preference for stratified deposits (e.g., Johnson and Brook 2011). This is mirrored in the management of surface archaeology in heritage sites, where emphasis is often placed on providing cultural interpretation as part of significance assessments. ...
... Increases in the density and diversity of lithic artifacts, for example, have been used to argue for greater degrees of sedentism and more intensive occupation, which is considered a response to onset of drier, less predictable ENSO conditions during this period (Smith 1986;Smith and Ross 2008). This is corroborated by continental-scale studies of radiocarbon determinations, which show greater frequencies during the mid to late Holocene Johnson and Brook 2011;Williams 2013). From this perspective, human habitation during the late Holocene is viewed in terms of greater investment in local resource extraction and greater degrees of social complexity as groups sought to manage resources for expanding population in an increasingly marginal environment (Williams et al. 2015). ...
The generative nature of the archaeological record stands in contrast with reconstructive goals of
the discipline. This is particularly evident in discussions of surface archaeology, which is often considered
deficient for reconstructing human behavior in the past when compared with subsurface deposits. We look
at a case study from Rutherfords Creek in arid southeastern Australia, where lithics and combustion
features appear in differing densities across the surface. These have been interpreted variably in terms
of settlement patterns; however, the relationships between accumulation, visibility, and preservation are
complex. This study addresses these relationships in terms of formation dynamics, drawing out patterns
from surface assemblages that bear on the mobility and resilience of the ancestral Aboriginal populations
that occupied Rutherfords Creek during the late Holocene. A different view of the record emerges, one that
foregrounds the notions of reversibility in the patterning to identify the kinds of questions the record might
be most fruitfully brought to bear on, with implications for both surface and subsurface archaeology.
... The proliferation of the technique probably began with Gamble and colleagues (2005), who first identified 'population events' across Europe through the LGM using a large radiocarbon dataset from Europe. This paved the way for a large number of other studies around the world, most notably works on population histories through the terminal Pleistocene and Holocene in Europe, North America, South America, and Japan (e.g., Barbarena, Mendez, & Eugina de Porras, 2016;Barbarena, Prates, & Eugenia de Porras, 2015;Buchannan, Collard, & Edinborough, 2008;Buchanan, Hamilton, Edinborough, O'Brien, & Collard, 2011;Collard, Buchanan, Hamilton, & O'Brien, 2010;Collard, Edinborough, Shennan, & Thomas, 2010;Crema, Habu, Kobayashi, & Madella, 2016;Downey, Randall Hass, & Shennan, 2016;Gayo, Latorre, & Santoro, 2015;Robinson, Zahid, Codding, Hass, & Kelly 2019;Shennan & Edinborough, 2007;Shennan et al., 2013) and revolutionary work to de velop a technique to correct radiocarbon data for taphonomic loss through time (e.g., Johnson & Brook, 2011;Surovell & Brantingham, 2007;Surovell, Byrd Finley, Smith, Brantingham, & Kelly, 2009;Timpson et al., 2014) and/or spatial bias (Crema, Bevan, & Shennan, 2017). Similar to other geochronological fields, in recent years, researchers are continuing to refine the technique with increasingly complex exploration of Bayesian modelling and kernel density estimates (see Crema & Shoda, 2021, for discussion and re view). ...
The use of radiocarbon data as a proxy for past human demography has become common in many parts of the world with increasingly sophisticated techniques developed in the last decade. Australian archaeologists have been at the forefront of this research. Using this technique, the authors show that at a continent scale Aboriginal population remained low—in the tens of thousands—throughout the Pleistocene, followed by a stepwise growth in the last 10,000 years, and culminating at ~1.15 million in the Late Holocene. The Last Glacial Maximum resulted in significant disruption to populations, with recent evidence suggesting a prolonged recovery from the event, hindered by sea-level change through the terminal Pleistocene. This chapter hypothesises that increasing population during the Early Holocene, along with environmental packing from a reducing landmass, established the conditions contributing to the complex societies observed later in the Holocene and up to the ethnographic period. While radiocarbon approaches to exploring demography have been subject to frequent criticism, virtually all are explicitly addressed in sophisticated applications of the approach, and the authors’ findings continue to be proven robust as more archaeological data becomes available. For instance, the authors’ demonstration that initial seeding population at ~50,000 years ago was ~1000–3000 people and likely involved a deliberate act of exploration has been validated by a plethora of recent studies. The authors suggest a number of temporal and spatial areas that should form the focus of further archaeological research to fill in current knowledge gaps.
... However, modelling has indicated that the contribution of the dingo to the loss of the devil on mainland Australia may have been relatively small (Prowse et al. 2014). Alternatively, the archaeological record suggests that from about 5000 BP the human population on mainland Australia went through a period of 'intensification', consisting of occupation of more habitat types, technological change, more sedentary behaviour and population growth (Lourandos 1997, Johnson and Wroe 2003, Johnson and Brook 2011. Intensification might have caused increased competition with and hunting of devils by people (Johnson and Wroe 2003). ...
The possible role of climate change in late Quaternary animal extinctions is hotly debated, yet few studies have investigated its direct effects on animal physiology to assess whether past climate changes might have had significant impacts on now‐extinct species. Here we test whether climate change could have imposed physiological stress on the Tasmanian devil Sarcophilus harrisii during the mid‐Holocene, when the species went extinct on mainland Australia. Physiological values for the devil were quantified using mechanistic niche models of energy and water requirements for thermoregulation, and soil‐moisture‐based indices of plant stress from drought to indirectly represent food and water availability. The spatial pervasiveness, extremity and frequency of physiological stresses were compared between a period of known climatic and presumed demographic stability (8000–6010 BP) and the extinction period (5000–3010 BP). We found no evidence of widespread negative effects of climate on physiological parameters for the devil on the mainland during its extinction window. This leaves cultural and demographic changes in the human population or competition from the dingo Canis dingo as the main contending hypotheses to explain mainland loss of the devil in the mid‐Holocene.
The late 1960s and the 1970s saw palaeodemography emerge as a new field, with preliminary methods, applications and issues developed and noted by a number of archaeologists, biological anthropologists, and demographers. Palaeodemography is the study of the dynamics of past populations, typically those that lack historical census data. This chapter explores how demographic theory and methods have been integrated into palaeodemography within the context of archaeology. It discusses the manner in which theory has influenced palaeodemography, including the amalgamation of theoretical concepts into palaeodemographic methods and the interpretive framework in which analyses are contextualized. The chapter discusses at length the development of methods in palaeodemography and how these have evolved over time and responded to criticisms from within and outside the field. Palaeodemographic methods were originally derived from demographic approaches but have evolved to meet the requirements and challenges of working with bioarchaeological data.
Large anthropogenic ¹⁴ C datasets are widely used to generate summed probability distributions (SPDs) as a proxy for past human population levels. However, SPDs are a poor proxy when datasets are small, bearing little relationship to true population dynamics. Instead, more robust inferences can be achieved by directly modelling the population and assessing the model likelihood given the data. We introduce the R package ADMUR which uses a continuous piecewise linear (CPL) model of population change, calculates the model likelihood given a ¹⁴ C dataset, estimates credible intervals using Markov chain Monte Carlo, applies a goodness-of-fit test, and uses the Schwarz Criterion to compare CPL models. We demonstrate the efficacy of this method using toy data, showing that spurious dynamics are avoided when sample sizes are small, and true population dynamics are recovered as sample sizes increase. Finally, we use an improved ¹⁴ C dataset for the South American Arid Diagonal to compare CPL modelling to current simulation methods, and identify three Holocene phases when population trajectory estimates changed from rapid initial growth of 4.15% per generation to a decline of 0.05% per generation between 10 821 and 7055 yr BP, then gently grew at 0.58% per generation until 2500 yr BP.
This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’.
Hunter–gatherer population growth rate estimates extracted from archaeological proxies and ethnographic data show remarkable differences, as archaeological estimates are orders of magnitude smaller than ethnographic and historical estimates. This could imply that prehistoric hunter–gatherers were demographically different from recent hunter–gatherers. However, we show that the resolution of archaeological human population proxies is not sufficiently high to detect actual population dynamics and growth rates that can be observed in the historical and ethnographic data. We argue that archaeological and ethnographic population growth rates measure different things; therefore, they are not directly comparable. While ethnographic growth rate estimates of hunter–gatherer populations are directly linked to underlying demographic parameters, archaeological estimates track changes in the long-term mean population size, which reflects changes in the environmental productivity that provide the ultimate constraint for forager population growth. We further argue that because of this constraining effect, hunter–gatherer populations cannot exhibit long-term growth independently of increasing environmental productivity.
This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’.
For decades, researchers have employed sets of radiocarbon dates to reconstruct trends in ancient human populations. The overarching assumption in this analysis is that the frequency of dates is proportional to the magnitude of past human activity. Thus, the distribution of summed or otherwise summarized dates is used to extrapolate population density and mobility patterns. There are, however, a number of underlying assumptions associated with this analysis that workers address to varying degrees and which, if false and not critically accounted for, will introduce bias, misrepresent the magnitude of activity, and ultimately prove misleading in archaeological interpretations. In this regard, research has so far mainly focused on correcting for the effects of time-dependent degradation of archaeological sites and constituent materials, calibration irregularities, and the efficacy of the statistical methods used. Assumptions directly related to sample processing in radiocarbon dating, however, are less discussed in ‘14C-dates-as-data’ analyses. It is, for example, assumed that all carbonaceous materials will yield sufficient, endogenous carbon for radiocarbon measurement. Yet sample failure in radiocarbon dating is common and contingent on, largely, deterministic factors such as post-depositional environment. Sets of radiocarbon dates analyzed, therefore, represent successful measurements independent of reliability. In this work, we discuss the biases introduced by challenges in radiocarbon processing and their impact on 14C-dates-as-data studies.
The wetter tropical zones of northern Australia are linked by their monsoonal climates. Their archaeology shows its own distinctive pattern as well, and rock-art is an important source of evidence and insight. This study focusses on a part of Queensland, setting this local sequence alongside Arnhem Land (reported by the paper of Taçon & Brockwell) and in the northern pattern as a whole.
This book is an introduction to the archaeology of Australia from prehistoric times to the eighteenth century AD. It is the only up-to-date textbook on the subject and is designed for undergraduate courses, based on the author's considerable experience of teaching at the Australian National University. Lucidly written, it shows the diversity and colourfulness of the history of humanity in the southern continent. The Archaeology of Ancient Australia demonstrates with an array of illustrations and clear descriptions of key archaeological evidence from Australia a thorough evaluation of Australian prehistory. Readers are shown how this human past can be reconstructed from archaeological evidence, supplemented by information from genetics, environmental sciences, anthropology, and history. The result is a challenging view about how varied human life in the ancient past has been.
This paper illustrates the potential of rock art for understanding the past. It uses the visual specificity of rock paintings in the Kimberley, N.W. Australia, to monitor the development of spear and spearthrower technology over time. For instance, only simple, hand-thrown spears are depicted in the earliest Kimberley rock painting styles, with spearthrowers and composite spears first appearing during the late Bradshaw and Clothes Peg Figure Periods, respectively. The rock painting sequence also depicts changes in spearthrower morphology and size, the appearance of stone spear points, and post-European use of metal spear heads. We conclude that rock art can provide evidence at a level of resolution normally absent from archaeology.
Australia, a dry island continent in mid latitude, spans from tropical to cold temperate regions; long isolation has given it its own flora and fauna. Environmental changes in the late Quaternary have had their own and special courses in the continent and its several regions. The role of fires set by people is an important issue in the changing "natural' landscape. -Author
