Evolutionary Implications of Non-human Primate Diets

Extant non-human primates are our closest living relatives and knowledge of their diets serves as a focus for hypotheses about past diets. We now know that the diets of extant primates vary from almost total folivory to considerable faunivory. Subsistence strategies of extant primates and stable isotope ratio data constrain dietary scenarios for fossil primates, including hominins. Among extant primates, significant faunivory occurs only in species of <1 kg body weight. Among those >1 kg body weight, smaller primates feed on fruit or fruit with insects, and larger ones on fruit and foliage, including leaves, pith, stems, flowers, and bark. Fossil hominins fall into the size range for fruit and foliage-eating.

Shell Middens and Seashores

Studies on Middle and Late Pleistocene hominin dietary adaptations have argued that aquatic foods played a key role during this evolutionary process. This chapter presents a summary account on the use and significance of marine resources, particularly shellfish, for early modern humans in southern Africa during oxygen isotope stages (OIS) 6–4. The methods used to identify, quantify, and compare archaeomalacological assemblages in South Africa and beyond, their drawbacks, as well as palaeoenvironmental, taphonomical and foraging considerations necessary to evaluate these data are discussed. The significance of diet broadening in the context of emerging modern humans about 160 ka and their exit out of Africa ~80–60 ka is reflected upon in the light of coastal adaptations by other early hominins groups elsewhere, such as Neanderthals in the Mediterranean Basin. The implications of longer residential permanence and higher population densities generally possible near productive shorelines are also examined.

Diet, Nutrition, and Disease across the Lifespan

Diet and nutrition need to be adequate to sustain human growth, sexual maturation, reproduction, and the physical labour needed to obtain food and support the successful maturation of offspring to reproductive age. This chapter examines human diet and nutrition as they relate to infectious disease experience, and how nutrition and infection influence the human life course, which is organized according to life history stages. Human life history theory organizes growth and reproduction into largely exclusive processes: available energy goes first into the former, and then, after puberty, into the latter. Human life history is extremely plastic, with child growth, onset of sexual maturity, fecundity and longevity all being sensitive to nutrition. Such plasticity has been fundamental to human ecological success and it is important to understand it to be able to interpret evidence for biological quality of life among past populations.

An Isotopic Anthropology of Ancient Maya Diets

The ancient Maya are known to have relied heavily on maize horticulture. In spite of the fact that maize was responsible for both the ideological and physical survival of the Maya, there was significant variability in the degree to which it was consumed. In this chapter, direct evidence of food consumption provided by the stable isotope composition of carbon and nitrogen is reviewed in terms of variability that existed across time, space, and social variables. Relationships between diet and significant temporal developments such as agricultural intensification, the collapse of Classic Maya society, and the Spanish conquest are examined, along with the use of diet to reconstruct political economies, gender, and status differentiation.

Dietary Shifts at the Mesolithic–Neolithic Transition in Europe

The nature of the transition to agriculture has been widely debated, particularly in the context of north-western Europe, where stable carbon and nitrogen isotope data have been argued to indicate a rapid, sharp shift in diet. However, other lines of evidence sometimes suggest a less complete break. This chapter provides a broad overview of this debate, drawing on the large amount of isotope data now available that permits wider regional considerations of trends in coastal and inland contexts across Europe. A clear pattern emerges, with significant differences between Mesolithic and Neolithic isotopic composition, and, by inference, diets. There are a number of notable exceptions—at the individual, site, and regional levels. Some of these can be explained simply through terminology (i.e. ‘Neolithic’ being defined regionally through technology rather than subsistence), while others appear to relate to specific local environmental conditions placing foraging and farming on a more equal footing.

Plants, People and Diet in the Neolithic of Western Eurasia

The establishment of farming is a defining feature of the Neolithic period in western Asia and Europe. Decades of archaeobotanical research have clarified the spectrum of crops that emerged, geographical and diachronic variation in the cultivation of particular species, and, more recently, aspects of arable land management. Most of the available evidence, however, is indirect as regards the actual role of crops in the human (and animal) diet. Taking western Eurasia as a particularly well-researched frame of reference, this chapter uses case studies to illustrate complementary inferences from plant processing, storage, and food preparation evidence, on the one hand, and direct dietary inferences incorporating preserved human remains, on the other. This integrated approach supports the rarely tested assumption that crops were dietary staples in Neolithic communities, and that the ‘politics’ of their production and storage shaped social life.

The Evolution of Lactose Tolerance in Dairying Populations

Among the biocultural innovations associated with the Neolithic, dairying and the evolution of lactose tolerance is the most studied. Expression of the enzyme lactase, which digests the milk sugar lactose, decreases after weaning in mammals, including most humans. However, some humans express lactase throughout adulthood—a trait known as lactase persistence (LP). Striking observations about LP evolution include: (i) a strong correlation between LP frequency and a history of herding and dairying; (ii) genetic patterns indicating LP-associated variants have increased in frequency through natural selection; (iii) two of these variants have been experimentally shown to affect lactase expression in adults; and (iv) archaeological and ancient DNA data indicate dairying pre-dated the rise of LP-associated variants. This chapter reviews the biology and archaeology of LP, examines some of the hypotheses formulated to explain its distribution, and outlines how simulation modelling has contributed to our understanding of its evolution.

How Meat Made us Human

This chapter examines the oldest known archaeological evidence from 2.6–1.5 million years ago (Ma) from several sites in East Africa, to improve understanding of the diet and related behavioural capabilities of early human ancestors (hominins) from that period. The archaeological evidence from the period consists of both small scatters and large, dense concentrations of flaked stone tools often found with fossil bones of large animals. The proportions of different skeletal elements, particularly once-meaty limb bones, and the abundance of stone-tool butchery damage on those bones, indicate that by 1.84 Ma at the FLK Zinj site at Olduvai Gorge, hominins had first access to prey carcasses. Moreover, mortality (age at death) profiles suggest active hunting by early Homo rather than secondary access to scavenged carcasses. Evidently, early Homo was repeatedly transporting meaty portions of large carcasses for delayed consumption and probable food sharing—behaviours characteristic of humans, not apes.

Tooth Enamel Biogeochemistry and Early Hominin Diets

Biogeochemical studies of hominin dietary ecology began decades ago, and, despite refinements, the basic tools being used and questions being asked have changed little since then. Carbon isotope analyses have had the most impact, with numerous studies showing that up to c.4 Ma, early hominins consumed primarily C3 vegetation, as do extant apes, but thereafter consumption of C4 foods became conspicuous if variable. Paranthropus boisei completely abandoned the ancestral C3 diet by at least 2 Ma to become a C4 consumer, a rarity among primates. These shifts were accompanied by changes in the australopith masticatory package. Applications using trace elements, particularly strontium and barium, as trophic level indicators have been less successful, partly because the distributions of trace elements in foodwebs are poorly understood. Similarly, while the oxygen isotope composition of tooth enamel unquestionably reflects ecology, the influences are complex and too poorly understood to allow unambiguous interpretation.

How ‘Best’ to Determine Trophic Levels in Archaeological Agricultural Communities

Stable isotope ratios of bone collagen have been used to determine trophic levels in diverse archaeological populations. The longest established and arguably most successful isotope system has been nitrogen, followed by carbon, and more recently hydrogen. These trophic level proxies rely on a predictable change in isotope ratio with each trophic level step; however, this requirement may not always be met, which can lead to difficulties in interpreting archaeological evidence. In agricultural communities, in particular, there are several possible complications to the interpretation of nitrogen and carbon isotopes. Recent approaches to overcome these limitations include better quantification and understanding of the influences on consumer isotope ratios; inclusion of evidence from plant remains; further investigation of apatite δ13C—collagen δ13C spacing in bones; measurement of carbon and nitrogen isotope ratios in individual amino acids, rather than collagen; and development of other stable isotope proxies for trophic level, such as hydrogen isotopes.