This article focuses on hunter-gatherer impact on interglacial vegetation in Europe, using a case study from the Early Holocene (9200–8700 BP). We present a novel agent-based model, hereafter... Show moreThis article focuses on hunter-gatherer impact on interglacial vegetation in Europe, using a case study from the Early Holocene (9200–8700 BP). We present a novel agent-based model, hereafter referred to as HUMLAND (HUMan impact on LANDscapes), specifically developed to define key factors in continental-level vegetation changes via assessment of differences between pollen-based reconstruction and dynamic global vegetation model output (climate-based vegetation cover). The identified significant difference between these two datasets can be partially explained by the difference in the models themselves, but also by the fact that climate is not the sole factor responsible for vegetation change. Sensitivity analysis of HUMLAND showed that the intensity of anthropogenic vegetation modification mainly depended on three factors: the number of groups present, their preferences for vegetation openness around campsites, and the size of an area impacted by humans. Overall, both climate and human activities had strong impacts on vegetation openness during the study period. Our modelling results support the hypothesis that European ecosystems were strongly shaped by human activities already in the Mesolithic. Show less
NIKULINA, A.; MacDonald, K.; Scherjon, F.; Pearce, E.A.; Davoli, M.; Svenning, J.-C.; ... ; Roebroeks, W. 2022
We review palaeoenvironmental proxies and combinations of these relevant for understanding hunter-gatherer niche construction activities in pre-agricultural Europe. Our approach consists of two... Show moreWe review palaeoenvironmental proxies and combinations of these relevant for understanding hunter-gatherer niche construction activities in pre-agricultural Europe. Our approach consists of two steps: (1) identify the possible range of hunter-gatherer impacts on landscapes based on ethnographic studies; (2) evaluate proxies possibly reflecting these impacts for both the Eemian (Last Interglacial, Middle Palaeolithic) and the Early–Middle Holocene (Mesolithic). We found these paleoenvironmental proxies were not able to unequivocally establish clear-cut differences between specific anthropogenic, climatic and megafaunal impacts for either time period in this area. We discuss case studies for both periods and show that published evidence for Mesolithic manipulation of landscapes is based on the interpretation of comparable data as available for the Last Interglacial. If one applies the ‘Mesolithic’ interpretation schemes to the Neanderthal record, three common niche construction activities can be hypothesised: vegetation burning, plant manipulation and impact on animal species presence and abundance. Our review suggests that as strong a case can be made for a Neanderthal impact on landscapes as for anthropogenic landscape changes during the Mesolithic, even though the Neanderthal evidence comes from only one high-resolution site complex. Further research should include attempts (e.g. by means of modelling studies) to establish whether hunter-gatherer impact on landscapes played out at a local level only versus at a larger scale during both time periods, while we also need to obtain comparative data on the population sizes of Last Interglacial and Holocene hunter-gatherers, as these are usually inferred to have differed significantly. Show less
Little is known about the antiquity, nature, and scale of Pleistocene hunter-gatherer impact on their ecosystems, despite the importance for studies of conservation and human evolution. Such impact... Show moreLittle is known about the antiquity, nature, and scale of Pleistocene hunter-gatherer impact on their ecosystems, despite the importance for studies of conservation and human evolution. Such impact is likely to be limited, mainly because of low population densities, and challenging to detect and interpret in terms of cause-effect dynamics. We present high-resolution paleoenvironmental and archaeological data from the Last Interglacial locality of Neumark-Nord (Germany). Among the factors that shaped vegetation structure and succession in this lake landscape, we identify a distinct ecological footprint of hominin activities, including fire use. We compare these data with evidence from archaeological and baseline sites from the same region. At Neumark-Nord, notably open vegetation coincides with a virtually continuous c. 2000-year-long hominin presence, and the comparative data strongly suggest that hominins were a contributing factor. With an age of c. 125,000 years, Neumark-Nord provides an early example of a hominin role in vegetation transformation. Show less
Vaesen, K.; Scherjon, F.; Hemerik, L.; Verpoorte, A. 2019
The replacement of Neanderthals by Anatomically Modern Humans has typically been attributed to environmental pressure or a superiority of modern humans with respect to competition for resources.... Show moreThe replacement of Neanderthals by Anatomically Modern Humans has typically been attributed to environmental pressure or a superiority of modern humans with respect to competition for resources. Here we present two independent models that suggest that no such heatedly debated factors might be needed to account for the demise of Neanderthals. Starting from the observation that Neanderthal populations already were small before the arrival of modern humans, the models implement three factors that conservation biology identifies as critical for a small population’s persistence, namely inbreeding, Allee effects and stochasticity. Our results indicate that the disappearance of Neanderthals might have resided in the smallness of their population(s) alone: even if they had been identical to modern humans in their cognitive, social and cultural traits, and even in the absence of inter-specific competition, Neanderthals faced a considerable risk of extinction. Furthermore, we suggest that if modern humans contributed to the demise of Neanderthals, that contribution might have had nothing to do with resource competition, but rather with how the incoming populations geographically restructured the resident populations, in a way that reinforced Allee effects, and the effects of inbreeding and stochasticity. Show less
This study presents an agent-based simulation model exploring the patterns of presence and absence of Late Pleistocene Neanderthals in western Europe. HomininSpace implements a parameterized... Show moreThis study presents an agent-based simulation model exploring the patterns of presence and absence of Late Pleistocene Neanderthals in western Europe. HomininSpace implements a parameterized generic demographic and social model of hominin dispersal while avoiding parameter value biases and explicitly modelled handicaps. Models are simulated through time within a high-resolution environment where reconstructed temperatures and precipitation levels influence the carrying capacity of the landscape. Model parameter values are assigned and varied automatically while optimizing the match with Neanderthal archaeology using a Genetic Algorithm (GA) inspired by the processes of natural selection. The system is able to traverse the huge parameter space that is created by the complete set of all possible parameter value combinations to find those values that will result in a simulation that matches well with archaeological data in the form of radiometrically obtained presence data. Show less
With the proliferation of online learning, the future of classroom teaching has been called into question. However, the unfaltering popularity of brick-and-mortar courses indicates that direct... Show moreWith the proliferation of online learning, the future of classroom teaching has been called into question. However, the unfaltering popularity of brick-and-mortar courses indicates that direct access to expert knowledge and face-to-face engagements remain key considerations for students. Here we showcase a combination of these two worlds in a Small Private Online Course (SPOC). Compared to Massive Open Online Courses (MOOCs), SPOCs are developed for smaller and more dedicated target groups and depend on close engagement between teachers and students. This format enables educational providers to involve internal and external students and teachers alike and to make ample use of online resources. This paper is based upon our experiences of running a SPOC on ‘Modelling and Simulation in Archaeology’ at Leiden University. We review the process of developing and running the course aimed at teaching archaeology students computer programming skills, while supporting their development as professional archaeologists and responsible academics. Show less
Evidence for fire use becomes increasingly sparse the further back in time one looks. This is especially true for Palaeolithic assemblages. Primary evidence of fire use in the form of hearth... Show moreEvidence for fire use becomes increasingly sparse the further back in time one looks. This is especially true for Palaeolithic assemblages. Primary evidence of fire use in the form of hearth features tends to give way to clusters or sparse scatters of more durable heated stone fragments. In the absence of intact fireplaces, these thermally altered lithic remains have been used as a proxy for discerning relative degrees of fire use between archaeological layers and deposits. While previous experimental studies have demonstrated the physical effects of heat on stony artefacts, the mechanisms influencing the proportion of fire proxy evidence within archaeological layers remain understudied. This fundamental study is the first to apply a computer-based model (fiReproxies) in an attempt to simulate and quantify the complex interplay of factors that ultimately determine when and in what proportions lithic artefacts are heated by (anthropogenic) fires. As an illustrative example, we apply our model to two hypothetical archaeological layers that reflect glacial and interglacial conditions during the late Middle Palaeolithic within a generic simulated cave site to demonstrate how different environmental, behavioural and depositional factors like site surface area, sedimentation rate, occupation frequency, and fire size and intensity can, independently or together, significantly influence the visibility of archaeological fire signals. Show less
Archaeological indications for off-site burning by late Pleistocene and early Holocene hunter-gatherers present intransigent interpretive problems; by contrast, burning practices by recent hunter... Show moreArchaeological indications for off-site burning by late Pleistocene and early Holocene hunter-gatherers present intransigent interpretive problems; by contrast, burning practices by recent hunter-gatherers are well documented. Here, we present a systematic global inventory of extant burning practices-including the reasons for burning and the environmental setting of firing activities-and also discuss their visibility in the archaeological record. This inventory is based on ethnographic and historical texts. In historical times, off-site fire was used for a wide range of purposes, irrespective of age and gender, with significant advantages for its producers. While the reasons given for burning can vary between individuals, in the longer term, many hunter-gatherer firing practices created more mosaic types of environments than would have occurred naturally. The historical visibility of hunter-gatherer burning activities contrasts with the relative invisibility of such practices in the contemporary archaeological record, highlighting the difficulty of analyzing past use of fire. On the basis of its ethnographic importance, we suggest that diverse off-site fire use is as old as the regular use of fire. New multiproxy data from well-sampled sequences, analyzed at a local scale, is needed to test this hypothesis. Show less
This internal report from the faculty of Archaeology of the University of Leiden provides an overview of excavations done between 2004 and 2012 at the coastal area referred to as Happisburgh I at... Show moreThis internal report from the faculty of Archaeology of the University of Leiden provides an overview of excavations done between 2004 and 2012 at the coastal area referred to as Happisburgh I at the east Anglian coast. Here several excavations have produced archaeological and biological material relevant to early hominin occupation on the British coastal area. Show less
