Bovid Teeth Research Articles

Combined uranium-series and electron spin resonance dating from the Pliocene fossil sites of Aves and Milo's palaeocaves, Bolt's Farm, Cradle of Humankind, South Africa.

Bolt's Farm is the name given to a series of non-hominin bearing fossil sites that have often been suggested to be some of the oldest Pliocene sites in the Cradle of Humankind, South Africa. This article reports the results of the first combined Uranium-Series and Electron Spin Resonance (US-ESR) dating of bovid teeth at Milo's Cave and Aves Cave at Bolt's Farm. Both tooth enamel fragments and tooth enamel powder ages were presented for comparison. US-ESR, EU and LU models are calculated. Overall, the powder ages are consistent with previous uranium-lead and palaeomagnetic age estimates for the Aves Cave deposit, which suggest an age between ~3.15 and 2.61 Ma and provide the first ages for Milo's Cave dates to between ~3.1 and 2.7 Ma. The final ages were not overly dependent on the models used (US-ESR, LU or EU), which all overlap within error. These ages are all consistent with the biochronological age estimate (<3.4->2.6 Ma) based on the occurrence of Stage I Metridiochoerus andrewsi. Preliminary palaeomagnetic analysis from Milo's Cave indicates a reversal takes place at the site with predominantly intermediate directions, suggesting the deposit may date to the period between ~3.03 and 3.11 Ma within error of the ESR ages. This further suggests that there are no definitive examples of palaeocave deposits at Bolt's Farm older than 3.2 Ma. This research indicates that US-ESR dating has the potential to date fossil sites in the Cradle of Humankind to over 3 Ma. However, bulk sample analysis for US-ESR dating is recommended for sites over 3 Ma.

African bovid tribe classification using transfer learning and computer vision.

Objective analytical identification methods are still a minority in the praxis of paleobiological sciences. Subjective interpretation of fossils and their modifications remains a nonreplicable expert endeavor. Identification of African bovids is a crucial element in the reconstruction of paleo-landscapes, ungulate paleoecology, and, eventually, hominin adaptation and ecosystemic reconstruction. Recent analytical efforts drawing on Fourier functional analysis and discrimination methods applied to occlusal surfaces of teeth have provided a highly accurate framework to correctly classify African bovid tribes and taxa. Artificial intelligence tools, like computer vision, have also shown their potential to be objectively more accurate in the identification of taphonomic agency than human experts. For this reason, here we implement some of the most successful computer vision methods, using transfer learning and ensemble analysis, to classify bidimensional images of African bovid teeth and show that 92% of the large testing set of images of African bovid tribes analyzed could be correctly classified. This brings an objective tool to paleoecological interpretation, where bovid identification and paleoecological interpretation can be more confidently carried out.

Reference database of teeth images from the Family Bovidae

Researchers typically rely on fossils from the Family Bovidae to generate African paleoenvironmental reconstructions due to their strict ecological tendencies. Bovids have dominated the southern African fauna for the past four million years and, therefore, dominate the fossil faunal assemblages, especially isolated teeth. Traditionally, researchers reference modern and fossil comparative collections to identify teeth. However, researchers are limited by the specific type and number of bovids at each institution. B.O.V.I.D. (Bovidae Occlusal Visual IDentification) is a repository of images of the occlusal surface of bovid teeth. The dataset currently includes extant bovids from 7 tribes and 20 species (~3900). B.O.V.I.D. contains two scaled images per specimen: a color and a black and white (binarized) image. The database is a useful reference for identifying bovid teeth. The large sample size also allows one to observe the natural variation that exists in each taxa. The binarized images can be used in statistical shape analyses, such as taxonomic classification. B.O.V.I.D. is a valuable supplement to other methods for taxonomically identifying bovid teeth.

Sequential analyses of bovid tooth enamel and dentine collagen (δ18O, δ13C, δ15N): new insights into animal husbandry between the Late Neolithic and the Early Bronze Age at Tana del Barletta (Ligurian Prealps)

Tana del Barletta is an upland cave used from the Late Neolithic to the Middle Bronze Age, located in the vicinity of the coast in Liguria (NW Italy). The excavation revealed the presence of a faunal assemblage dominated by caprine and cattle remains. In order to gain new data on late prehistoric farming strategies (e.g. seasonal mobility, coastal grazing, animal diet), intra-tooth series of stable oxygen and carbon isotopes have been obtained from cattle and sheep/goat tooth enamel, along with intra-tooth series of nitrogen and carbon isotopes from cattle dentine collagen. Due to the prevalence of maxillary teeth, a modern calf has also been analysed to assess intra-individual isotopic differences between the maxillary and mandibular dentition. Modern data on oxygen isotope values of meteoric water from different altitudes around the area of the site were used as a reference for interpretation. The results indicate that the water ingested by the herd was mostly characterised by particularly low δ18O values, highlighting the importance of the uplands for the late prehistoric farmers of the region. However, the input of water sourced from lower elevations, especially during the winter months, cannot be dismissed. In addition, the nitrogen isotopic composition of cattle collagen rules out the ingestion of salt-tolerant vegetation or seaweed, suggesting that grazing did not occur directly on the coastal plain.

Climate and ecology of the palaeo-Agulhas Plain from stable carbon and oxygen isotopes in bovid tooth enamel from Nelson Bay Cave, South Africa

We measured δ13Cenamel and δ18Oenamel in 213 archaeological bovid teeth from Nelson Bay Cave (NBC), spanning the last 22 ka. We also recorded dental mesowear (occlusal relief [high versus low] and cusp shape [sharp, round, or blunt]) of all maxillary first and second molars from NBC. We use these values to explore glacial/interglacial shifts in bovid palaeoecology and to reconstruct aspects of the climate and environment of the Palaeo-Agulhas Plain. Our results indicate that at the time of the Last Glacial Maximum (LGM), there was a significantly greater proportion of C3 (winter-rainfall) grasses, although some C4 (summer rainfall) varieties were present. This conclusion is strengthened by correction for lower pCO2 at the LGM, leading to reduced carbon isotope fractionation in C3 photosynthesis. Terminal Pleistocene and Holocene grazers show a stronger C4 signal. Our findings are consistent with an eastwards extension of winter rainfall at the LGM, as proposed by some previous researchers. Beyond the broad distinction between browsers and grazers, δ13C values reflect species-specific dietary preferences. δ18O is more positive in browsers than grazers, probably due to their deriving a significant proportion of their water intake from evaporatively enriched leaf water. δ18O values do not show significant changes through time. The location of Nelson Bay Cave on the present-day interface between temperate and tropical weather systems means that this area is sensitive to past shifts in the relative importance of these systems. These findings therefore contribute to the reconstruction of past Southern Hemisphere climate dynamics on a glacial/interglacial time scale.

An analysis of the effect of tooth wear on bovid identification

Previous research provides a method for reducing the subjectivity in taxonomic identification of species in the family Bovidae by quantifying the occlusal surface of molar teeth using elliptical Fourier analysis. In this current study, we specifically test what effect medium to late tooth wear has on the identification of bovids when using the form (size and shape) of the occlusal surface to classify specimens. To achieve this, the classification results of teeth with ≥85% of their occlusal surface (training data set) were compared with the results of teeth with &lt;85% of their occlusal surface (test data set) due to wear. In the training data set, all tribes classified correctly &gt;87% of the time with both Alcelaphini and Reduncini classifying correctly &gt;90% of the time. The worn teeth in the test data set classified correctly at lower rates, but all tribes still collectively had a good classification accuracy (&gt;60%) with classification of Alcelaphini and Tragelaphini at &gt;75% and Reduncini at &gt;65%. Hippotragini classified correctly 50% of the time and Neotragini 42%. The one worn Bovini tooth in the test data set was classified as that of a Hippotragini. The classification rates of teeth with medium to late wear were lower than the unworn teeth, but not so low as to suggest that this methodology for identifying bovid teeth is inappropriate for worn teeth, especially when supplementary to other methods.&#x0D; Significance:&#x0D; &#x0D; Worn teeth can be taxonomically identified by performing elliptical Fourier analysis on the occlusal surface of their teeth.&#x0D; While teeth with medium to late wear correctly classify at lower rates than relatively unworn ones, the methodology is a valuable supplement to other methods for taxonomically identifying bovid teeth. Worn teeth of the tribes Alcelaphini and Tragelaphini classify at the highest rates.&#x0D; &#x0D; Open data set: &#x0D; https://github.com/gjm112/TeethWear

Constraining time and ecology on the Zinj paleolandscape: Microwear and mesowear analyses of the archaeofaunal remains of FLK Zinj and DS (Bed I), compared to FLK North (Bed I) and BK (Bed II) at Olduvai Gorge (Tanzania)

Defining the time that any given archaeofaunal assemblage took to be accumulated is challenging. Understanding the time variable is crucial to interpret how early sites were formed and what these sites represent in terms of hominin behavior. Two complementary dental analysis techniques (microwear and mesowear) have been used to understand dietary niches of ungulates. Microwear has also specifically been used to detect the character of occupations at archaeological sites. Here, we apply these techniques to a selection of Olduvai sites. Microwear and mesowear analyses on bovid teeth from a set of anthropogenic sites (FLK Zinj, DS, BK) and a carnivore palimpsest (FLK North) yielded different results. Microwear data from the three anthropogenic sites are similar, reflecting short, seasonal occupations, in contrast with the carnivore assemblage, which suggests a more prolonged period of deposition. The similar microwear signal in the two pene-contemporaneous sites of FLK Zinj and DS is encouraging, but caution in its interpretation is applied because of limited tooth enamel preservation and the resulting small sample size. The results shown here must be considered as a baseline for future and more extensive studies. Both microwear and mesowear analyses show that the most common bovid taxa in the Bed I sites exhibit mixed feeding signals. This reinforces the caution about interpretations of dietary niches of extinct ungulates based on their modern counterparts and emphasizes that for some taxa, the adoption of a browsing or grazing diet is context (time and locus) specific.

A comparison of machine learning techniques for taxonomic classification of teeth from the Family Bovidae

This study explores the performance of machine learning algorithms on the classification of fossil teeth in the Family Bovidae. Isolated bovid teeth are typically the most common fossils found in southern Africa and they often constitute the basis for paleoenvironmental reconstructions. Taxonomic identification of fossil bovid teeth, however, is often imprecise and subjective. Using modern teeth with known taxons, machine learning algorithms can be trained to classify fossils. Previous work by Brophy et al. [Quantitative morphological analysis of bovid teeth and implications for paleoenvironmental reconstruction of plovers lake, Gauteng Province, South Africa, J. Archaeol. Sci. 41 (2014), pp. 376–388] uses elliptical Fourier analysis of the form (size and shape) of the outline of the occlusal surface of each tooth as features in a linear discriminant analysis (LDA) framework. This manuscript expands on that previous work by exploring how different machine learning approaches classify the teeth and testing which technique is best for classification. In addition to LDA, four other machine learning techniques were considered (neural networks, nuclear penalized multinomial regression,random forests, and support vector machines) with support vector machines and random forests performing the best in terms of log loss and classification rate.

Tsunami sedimentary deposits of Crete records climate during the ‘Minoan Warming Period’ (≈3350 yr BP)

Earthquakes or explosive eruptions generate tsunami, which are at the origin of thick and chaotic coastal sediments. These commonly fossiliferous deposits are formed instantaneously at the historical or geological timescale and therefore have the potential to provide snapshot records of past climates. In Crete, near the city of Palaikastro, crops out a 1- to 9-m-thick sedimentary layer deposited by a huge tsunami that has been previously estimated to be about 9 m high. The presence of volcanic ash, the geometry, the archeological and faunal contents of the sedimentary deposit along with radiocarbon dating converge for interpreting this tsunamite as coeval with the Minoan Santorini (Thera) eruption ≈3350 yr BP. During its drawback, the tsunami deposited rocky blocks and a muddy matrix containing mollusc shells dredged from the seabed as well as cattle skeletal remains and various artifacts belonging to the contemporaneous Minoan civilization. While the oxygen isotope compositions of terrestrial vertebrate bone remains most likely resulted from diagenetic alteration, those of a bovid tooth revealed that air temperatures during MM3 and LM1 periods were about 4°C higher than nowadays. Oxygen isotope measurements of marine mollusc shells also revealed that sea surface temperatures were higher by about 2°C. Those results compare with the 2.5°C temperature difference already estimated according to both δ2H and δ18O values of Greenland ice cores. Incremental sampling of marine gastropods and bovid teeth suggests that the seasonal amplitude was similar to that prevailing during the second half of the 20th century.

Examining the use of Amazon's Mechanical Turk for edge extraction of the occlusal surface of fossilized bovid teeth.

In order to reconstruct environments associated with Plio-Pleistocene hominins in southern Africa, researchers frequently rely upon the animals associated with the hominins, in particular, animals in the Family Bovidae. Bovids in southern Africa are typically identified by their teeth. However, identifying the taxon of a bovid tooth is challenging due to various biasing factors. Furthermore, inaccurate identification of fossil bovids can have significant consequences on the reconstructed paleoenvironment. Recent research on the classification of bovid fossil teeth has relied on using elliptical Fourier analysis to summarize the shape of the outline of the occlusal surface of the tooth and the resulting harmonic amplitudes. Currently, an expert in the field must manually place landmarks around the edges of each tooth which is slow and time consuming. This study tests whether it is possible to crowdsource this task, while maintaining the necessary level of quality needed to perform a statistical analysis on each tooth. Amazon Mechanical Turk workers place landmarks on the edge of the tooth which is compared to the performance of an expert in the field. The results suggest that crowdsourcing the digitization process is reliable and replicable. With the technical aspects of digitization managed, researchers can concentrate on analyzing and interpreting the data.

New ages for the Upper Palaeolithic site of Xibaimaying in the Nihewan Basin, northern China: implications for small-tool and microblade industries in north-east Asia during Marine Isotope Stages 2 and 3

It has been suggested that the ‘small-tool’ and microblade Upper Palaeolithic industries coexisted in the Nihewan Basin of northern China for about 8–14 000 years during Marine Isotope Stage (MIS) 2. This inference was based on uranium-series ages of around 15 and 18 ka for bovid teeth recovered from the ‘latest’ small-tool site of Xibaimaying – the youngest occurrence of such tools in the region – and optically stimulated luminescence (OSL) dating of the earliest typical microblade site (Youfang: ∼26–29 ka). In this study, we re-dated the Xibaimaying site using single-grain OSL methods and the resulting ages indicate that the cultural layer was deposited 46 ± 3 ka ago, during MIS 3 – more than 20 millennia earlier than previously thought and older also than the so-called earliest ‘primitive’ and typical microblade tools found at Zhiyu (∼31–39 ka cal BP) and Youfang. These new ages for human occupation of Xibaimaying remove support for the parallel development of the small-tool and microblade industries in the Nihewan Basin during the Upper Palaeolithic, but reliable age estimates from additional sites are needed to confidently infer the nature of the chronological relationship between these two Upper Palaeolithic industries and the associated toolmakers.

Sequential δ13C and δ18O analyses of early Holocene bovid tooth enamel: Resolving vertical transhumance in Neolithic domesticated sheep and goats

Vertical transhumance is an important animal husbandry strategy that provides livestock with consistent access to pasture throughout the year and contributed to the intensification of sheep and goat husbandry in the Near East over 10,000years ago. Sequential carbon (δ13C) and oxygen (δ18O) isotope analyses of teeth from domesticated sheep and goats dating to the early Neolithic (9200 to 8700calyrB.P.) from a region of strong local topographic relief in southern Jordan exhibit inverse cyclical isotopic variation characterized by the coincidence of high δ18O values with low δ13C values indicating ingestion of 13C-depleted plants during the summer season. This pattern is consistent with vertical transhumance of caprines moving from low-elevation C3/C4 Irano-Turanian pastures to higher-elevation Mediterranean C3 pastures during the summer, but other seasonally directed animal husbandry strategies involving amendment of livestock diets generate a similar isotopic outcome. Caprine δ18O values referenced against the oxygen isotope ratios of contemporaneous obligate drinking cattle and non-obligate drinking mountain gazelle, bovids with limited home ranges, help distinguish the influence of meteoric water, 18O-enriched leaf water, and movement on the oxygen isotopic composition of sheep and goat tooth enamel. This approach assists in independent validation of vertical transhumance hypothesized for inverse cyclical variation in sequential δ13C and δ18O values and, also, decouples seasonal foddering from mobility in the carbon isotopic dietary record. The isotopic data presented here reveal that complex sheep and goat husbandry systems involving vertical transhumance, stationary flock-keeping, and winter foddering were in place by the late tenth millennium cal y.r. B.P. east of the Jordan Valley.

Nelson Bay Cave: A palaeoenvironmental reconstruction of the last 22 ka using stable carbon and oxygen isotopes from bovid tooth enamel

Nelson Bay Cave: A palaeoenvironmental reconstruction of the last 22 ka using stable carbon and oxygen isotopes from bovid tooth enamel

Palaeoenvironmental reconstruction based on carbon and oxygen stable isotope analysis of bovid tooth enamel from Elands Bay Cave, South Africa

Palaeoenvironmental reconstruction based on carbon and oxygen stable isotope analysis of bovid tooth enamel from Elands Bay Cave, South Africa

A Middle Pleistocene intense monsoonal episode from the Kapthurin Formation, Kenya: Stable isotopic evidence from bovid teeth and pedogenic carbonates

Carbon and oxygen isotope values of bovid tooth enamel and pedogenic carbonates were used to reconstruct the paleoenvironments associated with Middle Pleistocene archeological and paleontological sites from the Kapthurin Formation, Kenya. Fossil teeth and pedogenic carbonates were collected from lacustrine and fluvial facies (K3 and K3’) of the Kapthurin Formation (~543–509ka). Twenty teeth from six bovid tribes and twenty four pedogenic carbonates were sequentially sampled for stable oxygen and carbon analysis. The primary aims of this work are to reconstruct the vegetative habitats of bovids and environmental landscapes from the Kapthurin Formation, assessing the presence of C3, C4, or mixed vegetation and foragers. We also assess general paleoclimate factors, such as overall aridity, seasonal shifts in water availability, and broad habitat reconstructions. Carbon isotope values suggest a wide range of foraging strategies were available to bovids, and are characterized by both C3 dominated and C4 dominated diets, with little evidence for mixed feeders, while pedogenic carbonates suggest the landscape combined a mix of C3 and C4 vegetation sources, structurally similar to wooded grasslands. Paleoclimatic conditions, based on the reconstructed mean annual water deficit from δ18Oenamel values suggest a hyper mesic environment, most comparable to the modern Ituri rainforest, indicating a much wetter climate than the modern Lake Baringo Basin. This environment coincides with an intensified Middle Pleistocene African monsoonal system at the onset of Marine Isotope Stage 13 (~533ka). The Middle Pleistocene Lake Baringo regional habitat appears to have been one dominated by woodland areas, perennially active streams, marsh and sumpland environments, and a surrounding grassland ecosystem. This lush basin would have provided hominins with a diverse and productive ecosystem. Perhaps not surprisingly, archeological sites are found in all habitats, including wet, forested, and grassland environments.

Assessing long-term habitability at an eastern Sahara oasis: ESR dating of molluscs and herbivore teeth at Dakhleh Oasis, Egypt

In the northeastern Sahara, electron spin resonance (ESR) dating of when animals lived documents their habitability in Dakhleh Oasis, Egypt. A Middle Pleistocene paleolake(s) covered >1700 km2. At eastern Locality Dak348, 10 m thick, remnant lacustrine marls yielded Pleistocene fauna, rare artefacts, and plant casts. No obvious unconformity exists within these deposits. From upper horizons, a hartebeest tooth ESR dated at 195 ± 11 ka, correlates with Marine Isotope Stage (MIS) 7, while molluscs from a stratigraphically higher horizon averaged 89 ± 10 ka, correlating with MIS 5a/b. At western Locality Dak006, upslope deflation has left a temporally mixed surficial lag. Numerous lagged tooth fragments, independently dated by ESR, correlate with MIS 5 through 17. Fragments from a slope sand unit correlate with MIS stages 3 through 6. One bovid tooth associated with Younger Middle Stone Age artefacts in the base of the sand dated at 84 ± 7 ka (MIS 5a/b). Molluscs from Romano-Byzantine backdirt at a breached artesian vent dated to 8–15 ± 1 ka, suggesting that ponds formed during MIS 1 and 2. Even without well defined sedimentary contexts, ESR frequency data indicate that the oasis was habitable for herbivores during at least twelve stages in the Mid-Late Quaternary, and, therefore, likely also for humans.

New Discovery of Late Pleistocene Vertebrate Fossils from the Thimi Formation, Bhaktapur, Nepal

The fluvio-deltaic deposit of the Thimi Formation constitutes the uppermost part of the sedimentary sequence in the Kathmandu Basin, and is consists of carbonaceous clay, diatomaceous clay, silty-clay, silt, fine to medium grained sand, and thin to medium lignite beds. A 25 m thick fresh surface exposure of this formation at Phaidhoka, Bhaktapur yielded significant number of vertebrate fossils. The vertebrate fossils recovered from a sand bed at 14 m from the bottom of the sequence consist of six teeth. The teeth were identified as Bovid teeth. Along with Bovid molars fragments of limb and pelvic bones were also found belonging to the same individual.Journal of Institute of Science and Technology, 2015, 20(2): 73-75

Terminal Pleistocene and Holocene dynamics of southern Africa's winter rainfall zone based on carbon and oxygen isotope analysis of bovid tooth enamel from Elands Bay Cave

Southern Africa's winter rainfall zone (WRZ) is sensitive to changes in the earth's atmospheric and oceanic systems. This region has the potential to provide valuable insight into both regional and global paleoenvironmental dynamics. δ13C values of herbivore tooth enamel apatite reflect the proportions of C3 and C4 plants consumed. Here we present δ13C and δ18O values for 86 samples of tooth enamel from grazing and browsing bovids from the terminal Pleistocene and Holocene layers of Elands Bay Cave. The assemblage is dominated by steenbok (Raphicerus campestris) and grysbok (Raphicerus melanotis), which are known to feed on browse if available. However, the assemblage also includes large grazers. This study aims to determine whether the grasses they were eating were purely C3 (indicating a winter rainfall regime) or included a C4 component (signaling at least some summer rainfall). Results show that terminal Pleistocene and early Holocene vegetation communities were overwhelmingly C3. Late Holocene animals show slightly more enriched δ13C values, indicating that C4 grasses and perhaps some CAM plants utilizing C4 photosynthesis became more common. We infer that late Pleistocene (including the LGM) to early Holocene rainfall was largely restricted to the winter months. In the late Holocene, the increased proportion of C4/CAM vegetation may be indicative of changes in the position of storm tracks associated with the westerlies. This finding is consistent with other proxy records from southernmost Africa that suggest extension of the growing season into warmer months and/or relatively warmer temperatures during the late Holocene. δ18O values from enamel carbonate reflect a complex combination of meteoric drinking water, diet and physiological processes, and vary quite widely within and between species. Browsers have more positive δ18O than grazers, because a significant proportion of their moisture intake is from leaves enriched in 18O as a result of evapotranspiration.

Quantitative morphological analysis of bovid teeth and implications for paleoenvironmental reconstruction of Plovers Lake, Gauteng Province, South Africa

Fossil bovids are widely recognized as valuable ecological indicators, useful for reconstructing paleoenvironments associated with the hominins of Africa. Taxonomic identification of bovid remains in the Plio-Pleistocene fossil deposits of South Africa is based predominantly on dental remains, usually isolated teeth. However, factors such as age and degree of occlusal attrition of teeth often render taxonomic identification difficult. In addition, teeth of closely related bovid taxa can be particularly difficult to diagnose at the species level. Given that closely related bovid species often have differing ecological requirements, imprecise identification of bovids recovered from fossil sites can have significant ramifications when reconstructing environments. This study tests a method for accurately identifying bovid teeth using Elliptical Fourier Function Analysis in order to standardize their identification. The occlusal surfaces of maxillary and mandibular molars of bovid teeth from twenty extant species were digitized and the quantified tooth forms (size and shape) were statistically compared to other closely related bovids. Results indicated that all upper and lower teeth classified correctly using discriminant function analysis ≥85% of the time, suggesting that occlusal surface form can reliably differentiate between closely related, morphologically similar bovids.This method was applied to a sample of fossil bovid teeth previously identified as “medium-sized alcelaphine” from Plovers Lake, Gauteng Province, South Africa. Precise taxonomic identification of these alcelaphines result in the earliest recorded presence of Alcelaphus buselaphus and Connochaetes gnou in Gauteng Province, as well as potentially the earliest documented co-occurrence of these taxa alongside Connochaetes taurinus and Damaliscus dorcas in South Africa. Revising the paleoenvironment reconstructed for Plovers Lake suggests that it was likely not much more densely wooded than the area today. This contradicts the paleoenvironment previously inferred for the site, suggesting that overreliance on rare and/or small-bodied taxa in the initial report on Plovers Lake overemphasized the extent of woodlands that were indicated.

Local ecological profile for Paranthropus robustus in South Africa using stable carbon isotopes from associated bovid teeth

The biomechanical characterization of lower limb long bones in the chrono-ecogeographically diverse species Homo erectus is a fundamental step for assessing evolutionary changes in locomotor mode and body shape that occurred within the genus Homo. However, the samples available for the Early and earlier Middle Pleistocene are small and widely scattered in time and space, thus limiting our understanding of the nature and polarity of morphological trends. Compared to the African fossil record, loading histories based on detailed biomechanical assessment of diaphyseal strength in Indonesian H. erectus lower limb long bones have not been assessed. By using a microtomographic record (μCT), we performed a quantitative analysis of the biomechanical properties and structural organization of Kresna 11, a late Early Pleistocene adult H. erectus femoral shaft from the Sangiran Dome, Central Java. Relative to the modern human condition, Kresna 11 shows the predominant mediolateral cortical thickening (hypertrophy) and the distal displacement of the minimum diaphyseal breadth characteristic of early Homo femora, associated nonetheless with relatively modest cortical thickness within the mid-proximal portion. Synthetic functional imaging of the shaft through the planar representation of its inner structure has revealed distal thickening of the medial cortex, a feature previously unreported in H. erectus. The increase in relative mediolateral bending strength observed in Kresna 11 supports the hypothesis that, rather than simply reflecting differences in patterns of locomotor loading, biomechanical properties of the femoral shaft in archaic Homo are strongly influenced by body shape, i.e., variations in pelvic breadth and femoral neck length.