Hannah J. O'Regan

Modern macaque dietary heterogeneity assessed using stable isotope analysis of hair and bone.

Dietary variability might have been a major factor in the dispersal and subsequent persistence of the genus Macaca in both tropical and temperate areas. Macaques are found from northern Africa to Japan, yet there have been few systematic attempts to compare diets between different modern populations. Here we have taken a direct approach and sampled museum-curated tissues (hair and bone) of Macaca mulatta (rhesus macaques) for carbon and nitrogen stable isotope dietary analyses. Samples from India, Vietnam, and Burma (Myanmar) were taken, representing both tropical and temperate populations. The delta(13)C values obtained from hair show that the temperate macaques, particularly those from Uttar Pradesh, have a delta(13)C signature that indicates at least some use of C(4) resources, while the tropical individuals have a C(3)-based diet. However, delta(13)C values from bone bioapatite indicate a C(3)-based diet for all specimens and they do not show the C(4) usage seen in the hair of some animals, possibly because bone represents a much longer turnover period than that of hair. The results of delta(15)N analyses grouped animals by geographic region of origin, which may be related to local soil nitrogen values. The greatest variation in delta(15)N values was seen in the specimens from Burma, which may be partly due to seasonality, as specimens were collected at different times of year. We also investigated the relationship between the hair, bone collagen, and bone bioapatite delta(13)C results, and found that they are highly correlated, and that one tissue can be used to extrapolate results for another. However, our results also suggest that hair may pick up discrete feeding traces (such as seasonal usage), which are lost when only bone collagen and bioapatite are examined. This has important implications for dietary reconstructions of archaeological and paleontological populations.

An ecological reassessment of the southern African carnivore guild: a case study from Member 4, Sterkfontein, South Africa

The southern African late Pliocene to early Pleistocene carnivore guild was much larger than that of the present day. Understanding how this guild may have functioned is important for the reconstruction of carnivore-hominin interactions and to assess the potential for hominin scavenging in southern Africa. In modern ecosystems, the coexistence of larger carnivore species is constrained by several factors, which include high levels of interspecific competition. Here, the composition of the fossil carnivore guild is examined using Sterkfontein Member 4 (Cradle of Humankind, South Africa) as a case study. Sterkfontein Member 4 contains 10 larger carnivore taxa (body mass >21.5 kg) and may also contain two Australopithecus species. Two possible causes of higher numbers of carnivore species in the South African fossil record are initially considered. First, that there is a bias introduced through comparing assemblages of differing sizes; second, carnivore biodiversity may have been artificially inflated due to previous taxonomic splitting of carnivore species, such as Crocuta. These possibilities are rejected and modern ecological data are used to construct a simple spatial model to determine how many carnivores could have co-existed. Although the resulting model indicates that the carnivore taxa present in Member 4 could have co-occurred, modern ecological studies indicate that it is highly unlikely that they would have co-existed simultaneously. Considering the complex depositional processes that operate in the southern African cave sites, it is proposed that the larger carnivore guild observed in the Sterkfontein Member 4 fossil assemblage is a palimpsest created by time-averaging. In light of this, we suggest that sites which have a large number of carnivore taxa should be examined for time-averaging, while those sites which have relatively few species may be a better reflection of carnivore communities.

The ‘mosaic habitat’ concept in human evolution: past and present

The habitats preferred by hominins and other species are an important theme in palaeoanthropology, and the ‘mosaic habitat’ (also referred to as habitat heterogeneity) has been a central concept in this regard for the last four decades. Here we explore the development of this concept – loosely defined as a range of different habitat types, such as woodlands, riverine forest and savannah within a limited spatial area – in studies of human evolution over the last 60 years or so. We outline the key developments that took place before and around the time when the term ‘mosaic’ came to wider palaeoanthropological attention. To achieve this, we used an analysis of the published literature, a study of illustrations of hominin evolution from 1925 onwards and an email survey of senior researchers in palaeoanthropology and related fields. We found that the term ‘mosaic’ starts to be applied in palaeoanthropological thinking during the 1970s due to the work of a number of researchers, including Karl Butzer and Glynn Isaac, with the earliest usage we have found of ‘mosaic’ in specific reference to hominin habitats being by Adriaan Kortlandt (1972). While we observe a steady increase in the numbers of publications reporting mosaic palaeohabitats, in keeping with the growing interest and specialisation in various methods of palaeoenvironmental reconstruction, we also note that there is a lack of critical studies that define this habitat, or examine the temporal and spatial scales associated with it. The general consensus within the field is that the concept now requires more detailed definition and study to evaluate its role in human evolution.

Multi-tissue analysis of oxygen isotopes in wild rhesus macaques (Macaca mulatta)

Oxygen isotopes in animal tissues are directly related to body water composition and thus the environment. Accurate measurement of animal tissue δ(18)O provides information about local climate, an animals geographical origin and subsequent movements, with wide applications in palaeobiology and forensic science. The genesis and evolution of tissue-based oxygen isotopes within species and within individuals are complex. We present the first data, for non-human primates, rhesus macaques (Macaca mulatta), on the relationship between oxygen isotope sources in bio-apatite (PO(4) and PCO(3)) and hair taken from six sample sites in Asia, ranging from western India to northern Vietnam. The range of values is similar within each tissue type, with good correlation between tissues (r = 0.791 to 0.908), allowing cross-tissue extrapolations. This is important when the availability of suitable tissues is limited. Biological interpretation of the small data set is difficult: macaque diets are eclectic, and the samples are from various locations. However, factors such as overall climate, precipitation quantity and source, and altitude are clearly influencing the results for each discrete geographical grouping. Future work could be aimed at assessing δ(18)O tissue associations for other species as the relationships appear to be species-specific.

Where are the Non-Human Bog Bodies?

Abstract We draw attention to the rarity of non-human bog bodies, reviewing the small number from Britain and Ireland of which we are aware. We use this absence to argue that there is more to becoming a bog body than merely dying on a bog (or falling into a bog pool). Given the potential importance of non-human bog bodies to the interpretation of the human remains we stress the importance of the publication of any examples.

Scrubbing Up: Multi-Scale Investigation of Woody Encroachment in a Southern African Savannah

Changes in the extent of woody vegetation represent a major conservation question in many savannah systems around the globe. To address the problem of the current lack of broad-scale cost-effective tools for land cover monitoring in complex savannah environments, we use a multi-scale approach to quantifying vegetation change in Kruger National Park (KNP), South Africa. We test whether medium spatial resolution satellite data (Landsat, existing back to the 1970s), which have pixel sizes larger than typical vegetation patches, can nevertheless capture the thematic detail required to detect woody encroachment in savannahs. We quantify vegetation change over a 13-year period in KNP, examine the changes that have occurred, assess the drivers of these changes, and compare appropriate remote sensing data sources for monitoring change. We generate land cover maps for three areas of southern KNP using very high resolution (VHR) and medium resolution satellite sensor imagery from February 2001 to 2014. Considerable land cover change has occurred, with large increases in shrubs replacing both trees and grassland. Examination of exclosure areas and potential environmental driver data suggests two mechanisms: elephant herbivory removing trees and at least one separate mechanism responsible for conversion of grassland to shrubs, theorised to be increasing atmospheric CO2. Thus, the combination of these mechanisms causes the novel two-directional shrub encroachment that we observe (tree loss and grassland conversion). Multi-scale comparison of classifications indicates that although spatial detail is lost when using medium resolution rather than VHR imagery for land cover classification (e.g., Landsat imagery cannot readily distinguish between tree and shrub classes, while VHR imagery can), the thematic detail contained within both VHR and medium resolution classifications is remarkably congruent. This suggests that medium resolution imagery contains sufficient thematic information for most broad-scale land cover monitoring requirements in heterogeneous savannahs, while having the benefits of being cost-free and providing a longer historical archive of data than VHR sources. We conclude that monitoring of broad-scale land cover change using remote sensing has considerable potential as a cost-effective tool for both better informing land management practitioners, and for monitoring the future landscape-scale impacts of management policies in savannahs.

The presence of the brown bear Ursus arctos in Holocene Britain: a review of the evidence

1. The brown bear, Ursus arctos, was Holocene Britain’s largest carnivoran and has appeared in recent rewilding discussions. 2. Despite widespread interest, we know very little about the species in Holocene Britain as few studies have been undertaken. This paper draws together information on the brown bear to examine the presence and extinction of bears through examination of the archaeological and palaeontological evidence. 3. Data were collected from published literature and museum catalogues. Information on the chronological date of the sites, number of specimens, and the body parts present were particularly sought. 4. A total of 86 sites were identified, 57 are well dated, 27 are of uncertain date but likely to be Holocene, and two have uncertain identifications. Very few specimens from non-archaeological sites (i.e. fens and caves) are well-dated, skewing the data towards anthropogenic sites such as settlements, castles, and graves. 5. Analysis of body part representation shows that the bear bones found in the Bronze Age, Iron Age and most of the early medieval period are from skins. All body parts are present during the Romano-British, medieval, and post-medieval period, indicating that live bears were present, and were probably imported for entertainment. 6. It seems the brown bear was rare throughout the Holocene, and based on current evidence two extinction scenarios can be put forward: extinction in the late Neolithic/early Bronze Age, or extinction in the early medieval period.

Felidae from Cooper's Cave, South Africa (Mammalia: Carnivora)

ABSTRACT The Coopers Cave System has produced a diverse fossil assemblage including the remains of Paranthropus robustus Broom, 1938, and early Homo Linnaeus, 1758. The majority of the faunal remains come from Coopers D, which dates to c. 1.5–1.4 Ma. Here we describe 158 craniodental and postcranial felid fossils from Coopers D, including Dinofelis cf. aronoki. These fossils indicate the presence of four large felid genera at Coopers D: Dinofelis Zdansky, 1924, Megantereon Croizet & Jobert, 1828, Panthera Oken, 1816 (two species) and Acinonyx Brookes, 1828, plus two smaller taxa: Caracal Gray, 1843 and Felis Linnaeus, 1758. This assemblage may mark the first appearance of the modern cheetah Acinonyx jubatus (Schreber, 1775) in Africa, as well the first occurrence of the East African species Dinofelis cf. aronoki in southern Africa. This taxon appears intermediate in features between Dinofelis barlowi (Broom, 1937) and Dinofelis piveteaui (Ewer, 1955). We compare the Coopers D felid assemblage with those from other sites in the Cradle of Humankind, Gauteng, and discuss several scenarios for the evolution of the genus Dinofelis in eastern and southern Africa.