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Perlman RF, Beehner JC, Koenig A, Lu A. Consumption of underground storage organs is associated with improved energetic status in a graminivorous primate. J Hum Evol 2024; 192:103545. [PMID: 38843698 DOI: 10.1016/j.jhevol.2024.103545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 04/07/2024] [Accepted: 04/14/2024] [Indexed: 06/23/2024]
Abstract
Early hominin species likely had access to open, grassy habitats where periodic reliance on underground storage organs (USOs) is hypothesized to have played a crucial dietary role. As the only living graminivorous primate today, geladas (Theropithecus gelada) provide a unique perspective for understanding the energetic consequences of seasonal consumption of USOs. Geladas rely heavily on above-ground grasses throughout the year, but when grass is seasonally less available, they feed more on USOs. To assess whether USOs fit the definition of fallback foods (i.e., foods that are difficult to access, less preferred, or both), we examined how foraging effort (measured via time spent feeding and moving) and energetic status (measured via urinary C-peptide) fluctuated during seasonal dietary changes in a population of wild geladas in the Simien Mountains National Park, Ethiopia. If, indeed, USOs are fallback foods, we predicted an increase in foraging effort and a decline in energetic status during the dry season, when geladas rely more heavily on USOs. We collected behavioral and physiological data from 13 adult gelada males across a 13-month period. As expected, we found that male geladas spent more time moving during drier months. However, counter to the hypothesis that USOs are fallback foods in geladas, urinary C-peptide concentrations were significantly higher during the dry season. We suggest that USOs may represent an energy-rich food item for geladas, but it remains unclear why USOs are not consumed year-round. Future work is needed to better understand seasonal variation in the availability, nutrient content, and digestibility of USOs. However, results indicate that exploiting USOs seasonally could have been a valuable dietary strategy for the evolutionary success of early hominins.
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Affiliation(s)
- Rachel F Perlman
- Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, Stony Brook, NY 11794-4364, USA; Program for Research Initiatives in Science & Math, John Jay College of Criminal Justice, City University of New York, New York, NY 10019, USA.
| | - Jacinta C Beehner
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109-1043, USA; Department of Anthropology, University of Michigan, Ann Arbor, MI 48109-1107, USA
| | - Andreas Koenig
- Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, Stony Brook, NY 11794-4364, USA; Department of Anthropology, Stony Brook University, Stony Brook, NY 11794-4364, USA
| | - Amy Lu
- Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, Stony Brook, NY 11794-4364, USA; Department of Anthropology, Stony Brook University, Stony Brook, NY 11794-4364, USA.
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2
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Botha MS, Cowling RM, De Vynck JC, Esler KJ, Potts AJ. The response of geophytes to continuous human foraging on the Cape south coast, South Africa and its implications for early hunter-gatherer mobility patterns. PeerJ 2022; 10:e13066. [PMID: 35529488 PMCID: PMC9074880 DOI: 10.7717/peerj.13066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 02/14/2022] [Indexed: 01/11/2023] Open
Abstract
Current ecological understanding of plants with underground storage organs (USOs) suggests they have, in general, low rates of recruitment and thus as a resource it should be rapidly exhausted, which likely had implications for hunter-gatherer mobility patterns. We focus on the resilience (defined here as the ability of species to persist after being harvested) of USOs to human foraging. Human foragers harvested all visible USO material from 19 plots spread across six Cape south coast (South Africa) vegetation types for three consecutive years (2015-2017) during the period of peak USO apparency (September-October). We expected the plots to be depleted after the first year of harvesting since the entire storage organ of the USO is removed during foraging, i.e. immediate and substantial declines from the first to the second harvest. However, over 50% of the total weight harvested in 2015 was harvested in 2016 and 2017; only after two consecutive years of harvesting, was there evidence of significantly lower yield (p = 0.034) than the first (2015) harvest. Novel emergence of new species and new individuals in year two and three buffered the decline of harvested USOs. We use our findings to make predictions on hunter-gatherer mobility patterns in this region compared to the Hadza in East Africa and the Alyawara in North Australia.
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Affiliation(s)
- M. Susan Botha
- Botany Department, African Centre for Coastal Palaeoscience, Gqeberha, Eastern Cape, South Africa
| | - Richard M. Cowling
- Botany Department, African Centre for Coastal Palaeoscience, Gqeberha, Eastern Cape, South Africa
| | - Jan C. De Vynck
- Botany Department, African Centre for Coastal Palaeoscience, Gqeberha, Eastern Cape, South Africa
| | - Karen J. Esler
- Stellenbosch University, Conservation Ecology & Entomology, Stellenbosch, Western Cape, South Africa
| | - Alastair J. Potts
- Botany Department, Nelson Mandela University, Gqeberha, Eastern Cape, South Africa
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3
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The cost of cooking for foragers. J Hum Evol 2021; 162:103091. [PMID: 34801770 DOI: 10.1016/j.jhevol.2021.103091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 11/23/2022]
Abstract
Cooked food provides more calories to a consumer than raw food. When our human ancestors adopted cooking, the result was an increase in the caloric value of the diet. Generating the heat to cook, however, requires fuel, and accessing fuel was and remains a common problem for humanity. Cooking also frequently requires monitoring, special technology and other investments. These cooking costs should vary greatly across multiple contexts. Here I explain how to quantify this cooking trade-off as the ratio of the energetic benefits of cooking to the increased cost in handling time and examine the implications for foragers, including the first of our ancestors to cook. Ethnographic and experimental return rates and nutritional analysis about important prey items exploited by ethnohistoric Numic foragers in the North American Great Basin provide a demonstration of how the costs of cooking impact different types of prey. Foragers should make choices about which prey to capture based on expectations about the costs involved to cook them. The results indicate that the caloric benefit achieved by cooking meat is quickly lost as the cost of cooking increases, whereas many plant foods are beneficially cooked across a range of cooking costs. These findings affirm the importance of plant foods, especially geophytes, among foragers, and are highly suggestive of their importance at the onset of cooking in the human lineage.
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4
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Fannin LD, Singels E, Esler KJ, Dominy NJ. Grit and consequence. Evol Anthropol 2021; 30:375-384. [PMID: 34652829 DOI: 10.1002/evan.21927] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 05/03/2021] [Accepted: 09/29/2021] [Indexed: 11/11/2022]
Abstract
Grit is implicated in several biological phenomena-it wears teeth, it fractures teeth, it drives tooth evolution, it elicits complex manual manipulations-any one of which could be described as a central topic in evolutionary anthropology. But what is grit? We hardly know because we tend to privilege the consequences of grit (it is abrasive) over its formal features, all but ignoring crucial variables such as mineral composition, material properties, and particle geometry (size, angularity), not to mention natural variation in the habitats of primates and their food surfaces. Few topics have animated so much debate and invited such cool indifference at the same time. Our goal here is to shine a light on grit, to put a philosophical lens on the nature of our discourse, and to call attention to large empirical voids that should be filled and folded into our understanding of primate natural history and evolution.
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Affiliation(s)
- Luke D Fannin
- Department of Anthropology, Dartmouth College, Hanover, New Hampshire, USA.,Graduate Program in Ecology, Evolution, Environment, and Society, Dartmouth College, Hanover, New Hampshire, USA
| | - Elzanne Singels
- Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa
| | - Karen J Esler
- Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa
| | - Nathaniel J Dominy
- Department of Anthropology, Dartmouth College, Hanover, New Hampshire, USA.,Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, USA
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5
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Gravel-Miguel C, Murray JK, Schoville BJ, Wren CD, Marean CW. Exploring variability in lithic armature discard in the archaeological record. J Hum Evol 2021; 155:102981. [PMID: 33848696 DOI: 10.1016/j.jhevol.2021.102981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 02/23/2021] [Accepted: 02/23/2021] [Indexed: 11/28/2022]
Abstract
The invention of projectile technology had important ramifications for hominin evolution. However, the number of stone points that could have been used as projectiles fluctuates in archaeological assemblages, making it difficult to define when projectile technology was first widely adopted and how its usage changed over time. Here we use an agent-based model to simulate a hunter-gatherer foraging system where armatures are dropped according to their usage. We explore the impact of interactions between human behaviors and the environmental constraints of a data-informed landscape on the distribution and number of lithic armatures found in archaeological assemblages. We ran 2400 simulations modeling different population sizes, rates of hunting with projectiles, and tool curation levels. For each simulation, we recorded the location of dropped armatures and calculated the number and percentage of used armatures that were discarded at habitation camps vs. lost during hunting. We used linear regression to identify the demographic, behavioral, and environmental factor(s) that best explained changes in these numbers and percentages. The model results show that in a well-controlled environment, most armatures used as projectile weapons are lost or discarded at hunting sites; only ∼4.5% of used armatures (or ∼2 armatures per year of simulation) are discarded in habitation camps where they would likely be excavated. These findings suggest that even rare hafted armatures found in the Early and Middle Stone Age could indicate a well-established use of such tools. Our model shows that interactions between reoccupation of archaeological sites, population size, rate of hunting with projectile weapons, and tool curation levels strongly influence the count of lithic armatures found in archaeological assemblages. Therefore, we argue that fluctuations in the counts of armatures documented at archaeological sites should be evaluated within their demographic and environmental contexts to better understand if they reflect spatiotemporal changes in hunting behavior.
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Affiliation(s)
- Claudine Gravel-Miguel
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA; Département d'anthropologie, Université de Montréal, Montréal, QC, Canada.
| | - John K Murray
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA
| | - Benjamin J Schoville
- School of Social Science, Faculty of Humanities and Social Sciences, The University of Queensland, St Lucia, Australia
| | - Colin D Wren
- Department of Anthropology, University of Colorado, Colorado Springs, CO, USA
| | - Curtis W Marean
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA; African Centre for Coastal Palaeoscience, Nelson Mandela University, Eastern Cape, South Africa
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6
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Wadley L, Backwell L, d'Errico F, Sievers C. Cooked starchy rhizomes in Africa 170 thousand years ago. Science 2020; 367:87-91. [PMID: 31896717 DOI: 10.1126/science.aaz5926] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 11/05/2019] [Indexed: 01/20/2023]
Abstract
Plant carbohydrates were undoubtedly consumed in antiquity, yet starchy geophytes were seldom preserved archaeologically. We report evidence for geophyte exploitation by early humans from at least 170,000 years ago. Charred rhizomes from Border Cave, South Africa, were identified to the genus Hypoxis L. by comparing the morphology and anatomy of ancient and modern rhizomes. Hypoxis angustifolia Lam., the likely taxon, proliferates in relatively well-watered areas of sub-Saharan Africa and in Yemen, Arabia. In those areas and possibly farther north during moist periods, Hypoxis rhizomes would have provided reliable and familiar carbohydrate sources for mobile groups.
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Affiliation(s)
- Lyn Wadley
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa.
| | - Lucinda Backwell
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa.,Instituto Superior de Estudios Sociales, ISES-CONICET, Tucumán, Argentina
| | - Francesco d'Errico
- Centre National de la Recherche Scientifique, UMR 5199-PACEA, Université de Bordeaux, Bâtiment B2, Allée Geoffroy Saint Hilaire, CS 50023, 33615 Pessac, France.,SFF Centre for Early Sapiens Behaviour (SapienCE), University of Bergen, Øysteinsgate 3, Postboks 7805, 5020 Bergen, Norway
| | - Christine Sievers
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, South Africa
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7
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Larbey C, Mentzer SM, Ligouis B, Wurz S, Jones MK. Cooked starchy food in hearths ca. 120 kya and 65 kya (MIS 5e and MIS 4) from Klasies River Cave, South Africa. J Hum Evol 2019; 131:210-227. [DOI: 10.1016/j.jhevol.2019.03.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/13/2019] [Accepted: 03/14/2019] [Indexed: 01/12/2023]
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8
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Loftus E, Lee-Thorp J, Leng M, Marean C, Sealy J. Seasonal scheduling of shellfish collection in the Middle and Later Stone Ages of southern Africa. J Hum Evol 2019; 128:1-16. [PMID: 30825979 DOI: 10.1016/j.jhevol.2018.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 12/06/2018] [Accepted: 12/14/2018] [Indexed: 10/27/2022]
Abstract
This study assesses the seasonal scheduling of shellfish harvesting among hunter-gatherer populations along the southernmost coast of South Africa, based on a large number of serial oxygen isotope analyses of marine mollusk shells from four archaeological sites. The south coast of South Africa boasts an exceptional record of coastal hunter-gatherer occupation spanning the Holocene, the last glacial cycle and beyond. The significance of coastal adaptations, in this region in particular, for later modern human evolution has been prominently debated. Shellfishing behaviors are an important focus for investigation given the dietary and scheduling implications and the abundant archaeological shell remains in numerous sites. Key to better understanding coastal foraging is whether it was limited to one particular season, or year-round. Yet, this has proven very difficult to establish by conventional archaeological methods. This study reconstructs seasonal harvesting patterns by calculating water temperatures from the final growth increment of shells. Results from two Later Stone Age sites, Nelson Bay Cave (together with the nearby Hoffman's Robberg Cave) and Byneskranskop 1, show a pronounced cool season signal, which is unexpected given previous ethnographic documentation of summer as the optimal season for shellfishing activities and inferences about hunter-gatherer scheduling and mobility in the late Holocene. Results from two Middle Stone Age sites, Klasies River and Pinnacle Point 5-6, show distinct seasonal patterns that likely reflect the seasonal availability of resources in the two locations. The Pinnacle Point 5-6 assemblage, which spans the MIS5-4 transition, records a marked shift in shellfishing seasonality at c. 71 ka that aligns with other indications of archaeological and environmental change at this time. We conclude that the scheduling and intensity of shellfishing in this region is affected by a suite of factors, including environmental and cultural drivers, rather than a single variable, such as population growth.
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Affiliation(s)
- Emma Loftus
- Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, 1-2 South Parks Road, OX1 3TG, UK; Merton College, University of Oxford, Merton Street, OX1 4JD, UK.
| | - Julia Lee-Thorp
- Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, 1-2 South Parks Road, OX1 3TG, UK
| | - Melanie Leng
- NERC Isotope Geoscience Laboratory Facilities, British Geological Survey, Keyworth, Nottingham NG12 5GG, UK; Centre for Environmental Geochemistry, School of Geography, University of Nottingham, Nottingham NG7 2RD, UK
| | - Curtis Marean
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, PO Box 874101, Tempe, AZ, 85287-4101, USA; African Centre for Coastal Palaeoscience, Nelson Mandela University, PO Box 77000, Port Elizabeth, 6031, South Africa
| | - Judith Sealy
- Department of Archaeology, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
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9
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Esteban I, Marean CW, Fisher EC, Karkanas P, Cabanes D, Albert RM. Phytoliths as an indicator of early modern humans plant gathering strategies, fire fuel and site occupation intensity during the Middle Stone Age at Pinnacle Point 5-6 (south coast, South Africa). PLoS One 2018; 13:e0198558. [PMID: 29864147 PMCID: PMC5986156 DOI: 10.1371/journal.pone.0198558] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/21/2018] [Indexed: 01/27/2023] Open
Abstract
The study of plant remains in archaeological sites, along with a better understanding of the use of plants by prehistoric populations, can help us shed light on changes in survival strategies of hunter-gatherers and consequent impacts on modern human cognition, social organization, and technology. The archaeological locality of Pinnacle Point (Mossel Bay, South Africa) includes a series of coastal caves, rock-shelters, and open-air sites with human occupations spanning the Acheulian through Middle Stone Age (MSA) and Later Stone Age (LSA). These sites have provided some of the earliest evidence for complex human behaviour and technology during the MSA. We used phytoliths-amorphous silica particles that are deposited in cells of plants-as a proxy for the reconstruction of past human plant foraging strategies on the south coast of South Africa during the Middle and Late Pleistocene, emphasizing the use and control of fire as well as other possible plant uses. We analysed sediment samples from the different occupation periods at the rock shelter Pinnacle Point 5-6 North (PP5-6N). We also present an overview of the taphonomic processes affecting phytolith preservation in this site that will be critical to conduct a more reliable interpretation of the original plant use in the rock shelter. Our study reports the first evidence of the intentional gathering and introduction into living areas of plants from the Restionaceae family by MSA hunter-gatherers inhabiting the south coast of South Africa. We suggest that humans inhabiting Pinnacle Point during short-term occupation events during Marine Isotope Stage (MIS) 5 built fast fires using mainly grasses with some wood from trees and/or shrubs for specific purposes, perhaps for shellfish cooking. With the onset of MIS 4 we observed a change in the plant gathering strategies towards the intentional and intensive exploitation of dry wood to improve, we hypothesise, combustion for heating silcrete. This human behaviour is associated with changes in stone tool technology, site occupation intensity and climate change.
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Affiliation(s)
- Irene Esteban
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa
- African Centre for Coastal Palaeoscience, Nelson Mandela University, Port Elizabeth, South Africa
- ERAAUB. Dept. Història i Arqueologia, Universitat de Barcelona, Barcelona, Spain
| | - Curtis W. Marean
- African Centre for Coastal Palaeoscience, Nelson Mandela University, Port Elizabeth, South Africa
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, United States of America
| | - Erich C. Fisher
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- African Centre for Coastal Palaeoscience, Nelson Mandela University, Port Elizabeth, South Africa
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, United States of America
| | - Panagiotis Karkanas
- The Malcolm H. Wiener Laboratory for Archaeological Science, American School of Classical Studies, Athens, Greece
| | - Dan Cabanes
- Department of Anthropology, Rutgers, the State University of New Jersey, Biological Sciences Building, New Brunswick, New Jersey, United States of America
- Center for Human Evolutionary Studies. Rutgers, the State University of New Jersey, Biological Sciences Building, New Brunswick, New Jersey, United States of America
| | - Rosa M. Albert
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- African Centre for Coastal Palaeoscience, Nelson Mandela University, Port Elizabeth, South Africa
- ERAAUB. Dept. Història i Arqueologia, Universitat de Barcelona, Barcelona, Spain
- ICREA, Barcelona, Spain
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10
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Marean CW. The transition to foraging for dense and predictable resources and its impact on the evolution of modern humans. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150239. [PMID: 27298470 PMCID: PMC4920296 DOI: 10.1098/rstb.2015.0239] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2016] [Indexed: 11/12/2022] Open
Abstract
Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence-elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter-gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans.This article is part of the themed issue 'Major transitions in human evolution'.
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Affiliation(s)
- Curtis W Marean
- School of Human Evolution and Social Change, Institute of Human Origins, Arizona State University, PO Box 872402, Tempe, AZ 85287-2402, USA Centre for Coastal Palaeoscience, Nelson Mandela Metropolitan University, Port Elizabeth, Eastern Cape 6031, South Africa
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11
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De Vynck JC, Cowling RM, Potts AJ, Marean CW. Seasonal availability of edible underground and aboveground carbohydrate resources to human foragers on the Cape south coast, South Africa. PeerJ 2016; 4:e1679. [PMID: 26925319 PMCID: PMC4768670 DOI: 10.7717/peerj.1679] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 01/20/2016] [Indexed: 11/21/2022] Open
Abstract
The coastal environments of South Africa’s Cape Floristic Region (CFR) provide some of the earliest and most abundant evidence for the emergence of cognitively modern humans. In particular, the south coast of the CFR provided a uniquely diverse resource base for hunter-gatherers, which included marine shellfish, game, and carbohydrate-bearing plants, especially those with Underground Storage Organs (USOs). It has been hypothesized that these resources underpinned the continuity of human occupation in the region since the Middle Pleistocene. Very little research has been conducted on the foraging potential of carbohydrate resources in the CFR. This study focuses on the seasonal availability of plants with edible carbohydrates at six-weekly intervals over a two-year period in four vegetation types on South Africa’s Cape south coast. Different plant species were considered available to foragers if the edible carbohydrate was directly (i.e. above-ground edible portions) or indirectly (above-ground indications to below-ground edible portions) visible to an expert botanist familiar with this landscape. A total of 52 edible plant species were recorded across all vegetation types. Of these, 33 species were geophytes with edible USOs and 21 species had aboveground edible carbohydrates. Limestone Fynbos had the richest flora, followed by Strandveld, Renosterveld and lastly, Sand Fynbos. The availability of plant species differed across vegetation types and between survey years. The number of available USO species was highest for a six-month period from winter to early summer (Jul–Dec) across all vegetation types. Months of lowest species’ availability were in mid-summer to early autumn (Jan–Apr); the early winter (May–Jun) values were variable, being highest in Limestone Fynbos. However, even during the late summer carbohydrate “crunch,” 25 carbohydrate bearing species were visible across the four vegetation types. To establish a robust resource landscape will require additional spatial mapping of plant species abundances. Nonetheless, our results demonstrate that plant-based carbohydrate resources available to Stone Age foragers of the Cape south coast, especially USOs belonging to the Iridaceae family, are likely to have comprised a reliable and nutritious source of calories over most of the year.
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Affiliation(s)
- Jan C De Vynck
- Centre for Coastal Palaeosciences, Nelson Mandela Metropolitan University , Port Elizabeth, Eastern Cape , South Africa
| | - Richard M Cowling
- Centre for Coastal Palaeosciences, Nelson Mandela Metropolitan University , Port Elizabeth, Eastern Cape , South Africa
| | - Alastair J Potts
- Centre for Coastal Palaeosciences, Nelson Mandela Metropolitan University , Port Elizabeth, Eastern Cape , South Africa
| | - Curtis W Marean
- Centre for Coastal Palaeosciences, Nelson Mandela Metropolitan University, Port Elizabeth, Eastern Cape, South Africa; Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, United States
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