Specimens of Australopithecus sediba from the site of Malapa, South Africa (dating from approximately 2 million years (Myr) ago) present a mix of primitive and derived traits that align the taxon with other Australopithecus species and with early Homo. Although much of the available cranial and postcranial material of Au. sediba has been described, its feeding ecology has not been investigated. Here we present results from the first extraction of plant phytoliths from dental calculus of an early hominin. We also consider stable carbon isotope and dental microwear texture data for Au. sediba in light of new palaeoenvironmental evidence. The two individuals examined consumed an almost exclusive C(3) diet that probably included harder foods, and both dicotyledons (for example, tree leaves, fruits, wood and bark) and monocotyledons (for example, grasses and sedges). Like Ardipithecus ramidus (approximately 4.4 Myr ago) and modern savanna chimpanzees, Au. sediba consumed C(3) foods in preference to widely available C(4) resources. The inferred consumption of C(3) monocotyledons, and wood or bark, increases the known variety of early hominin foods. The overall dietary pattern of these two individuals contrasts with available data for other hominins in the region and elsewhere.

Intra-tooth stable isotope analysis of dentine provides a more sensitive means to examine infant and childhood life history in the past than conventional cross-sectional analyses that rely on age-at-death. In addition, reconstructions of early diet and life history using an intra-tooth approach circumvent potential problems associated with mortality bias, which may operate strongly during infancy and childhood. We present new intra-tooth stable carbon and nitrogen isotope profiles in dentine collagen of early forming permanent teeth in a sample of adults from the Medieval Nubian site of Kulubnarti. We interpret the profiles in terms of weaning behavior and dietary history, and we compare profiles generated from first molars and canines to explore the degree to which these tooth types correspond. We then compare the profiles to the occurrence of linear enamel hypoplasia to assess the relationship between the timing of the weaning process and stress events. Finally, we compare the longitudinal profiles to cross-sectional stable isotope data obtained from rib collagen to investigate how life histories might differ between those that survived into adulthood and those that did not. Results suggest that canine and first molar profiles are in broad agreement, that hypoplastic stress events occurred during rather than before or after the weaning process in our sample, and that survivors appear to have weaned earlier than the average non-survivor. We suggest that this approach may be useful for addressing the effects of selective mortality on reconstructions of early life history and the relationship between early life history and morbidity.

Stable isotope analysis has become an important tool in ecology over the last 25 years. A wealth of ecological information is stored in animal tissues in the relative abundances of the stable isotopes of several elements, particularly carbon and nitrogen, because these isotopes navigate through ecological processes in predictable ways. Stable carbon and nitrogen isotopes have been measured in most primate taxonomic groups and have yielded information about dietary content, dietary variability, and habitat use. Stable isotopes have recently proven useful for addressing more fine-grained questions about niche dynamics and anthropogenic effects on feeding ecology. Here, we discuss stable carbon and nitrogen isotope systematics and critically review the published stable carbon and nitrogen isotope data for modern primates with a focus on the problems and prospects for future stable isotope applications in primatology.

Stable isotope analysis has long been used to study the dietary ecology of living and fossil primates, and there has been increasing interest in using stable isotopes to study primate habitat use and anthropogenic impacts on non-human primates. Here, we examine the stable carbon and nitrogen isotope compositions of chimpanzees (Pan troglodytes) from seven communities in Uganda across a continuum of habitat structure (closed to more open) and access to anthropogenic resources (no reliance to heavy reliance). In general, the hair δ(13) C, but not δ(15) N, values of these communities vary depending on forest structure and degree of anthropogenic influence. When integrated with previously published hair δ(13) C and δ(15) N values for Pan, it is apparent that modern "savanna" and "forest" Pan form discrete clusters in carbon and nitrogen isotope space, although there are exceptions probably relating to microhabitat specialization. The combined dataset also reveals that Pan δ(13) C values (but not δ(15) N values) are inversely related to rainfall (r(2)  = 0.62). We converted Pan hair δ(13) C values to enamel equivalents and made comparisons to the fossil hominoids Sivapithecus sp., Gigantopithecus blacki, Ardipithecus ramidus, and Australopithecus anamensis. The δ(13) C values of the fossil hominins Ar. ramidus and Au. anamensis do not cluster with the δ(13) C values of modern Pan in "forest" habitats, or with fossil hominoids that are believed to have inhabited forests. Am. J. Primatol. 78:1070-1085, 2016. © 2016 Wiley Periodicals, Inc.

Species’ partitioning of resources remains one of the most integral components for understanding community assembly. Analysis of stable carbon and nitrogen isotopes in animal tissues has the potential to help resolve patterns of partitioning because these proxies represent the individual’s diet and trophic niche, respectively. Using free-ranging rodents in a southern African savanna as a model community, we find that syntopic species within habitats occupy distinct isotope niches. Moreover, species with strongly overlapping isotope niches did not overlap in their spatial distribution patterns, suggesting an underlying effect of competitive exclusion. Niche conservatism appears to characterize the behaviour of most species in our sample - with little or no observed changes across habitats - with the exception of one species, Mastomys coucha. This species displayed a generalist distribution, being found in similar abundances across a variety of habitats. This spatial pattern was coupled with a generalist isotope niche that shifted across habitats, likely in response to changes in species composition over the same spatial gradient. The case for M. coucha supports contentions that past competition effects played a significant evolutionary role in shaping community structures of today, including the absence of strong interspecific niche overlaps within particular habitats. Our study highlights the value of stable isotope approaches to help resolve key questions in community ecology, and moreover introduces novel analytical approaches to quantifying isotope niche breadths and niche overlaps that are easily comparable with traditional metrices.

No abstract

ObjectivesLimited studies have focused on how European contact and colonialism impacted Native American oral microbiomes, specifically, the diversity of commensal or opportunistically pathogenic oral microbes, which may be associated with oral diseases. Here, we studied the oral microbiomes of pre‐contact Wichita Ancestors, in partnership with the Descendant community, The Wichita and Affiliated Tribes, Oklahoma, USA.Materials and MethodsSkeletal remains of 28 Wichita Ancestors from 20 archeological sites (dating approximately to 1250–1450 CE) were paleopathologically assessed for presence of dental calculus and oral disease. DNA was extracted from calculus, and partial uracil deglycosylase‐treated double‐stranded DNA libraries were shotgun‐sequenced using Illumina technology. DNA preservation was assessed, the microbial community was taxonomically profiled, and phylogenomic analyzes were conducted.ResultsPaleopathological analysis revealed signs of oral diseases such as caries and periodontitis. Calculus samples from 26 Ancestors yielded oral microbiomes with minimal extraneous contamination. Anaerolineaceae bacterium oral taxon 439 was found to be the most abundant bacterial species. Several Ancestors showed high abundance of bacteria typically associated with periodontitis such as Tannerella forsythia and Treponema denticola. Phylogenomic analyzes of Anaerolineaceae bacterium oral taxon 439 and T. forsythia revealed biogeographic structuring; strains present in the Wichita Ancestors clustered with strains from other pre‐contact Native Americans and were distinct from European and/or post‐contact American strains.DiscussionWe present the largest oral metagenome dataset from a pre‐contact Native American population and demonstrate the presence of distinct lineages of oral microbes specific to the pre‐contact Americas.

Carbon isotope analysis of fossil micromammal insectivores holds promise for resolving questions about past environments because these animals have restricted home ranges and are generalist feeders, thus their diets likely integrate ecological information about local habitats.In this study, we assessed the degree to which carbon isotope compositions of 35 three sympatric shrew species record spatial and temporal changes in habitat conditions 36 in a mosaic southern African savanna environment. Sampling sites were located within 2 37 km of one another, and microhabitat conditions ranged from very open (< 5% canopy 38 cover) to wooded (~60% canopy cover). We compared shrew hair  13 C values between microhabitat types, and across taxa, in order to test whether these data follow predictable patterns based on local vegetation.Shrew carbon isotope values varied with habitat in a predictable manner within our study area. While taxonomy also influenced  13 C values, this was largely due to 43 differences in habitat preferences of individual taxa and resultant variation in their relative abundance within each environment. Isotopic differences between habitat types were preserved within individual taxa where taxa occurred in multiple habitats. To complement this modern study, we performed isotopic analysis of the enamel of insecteating fossil micromammals from the hominin sites Gladysvale and Sterkfontein in the Cradle of Humankind, South Africa. This subset of fossil micromammals consumed primarily C 4 -derived carbon. 50