Papers by Robert Blumenschine
Paleobiology, 2009
Most functional interpretations of ziphodont dentition are based on limited morphometric, behavio... more Most functional interpretations of ziphodont dentition are based on limited morphometric, behavioral, and taphonomic studies, but few are based on controlled observations of a modern ziphodont consumer. The purpose of this study is to determine through controlled feeding observations if the behaviors indicative of a ziphodont consumer are reflected by tooth marks left on bone surfaces by Varanus komodoensis, the Komodo monitor. We document feeding behavior, expand upon dental function, and correlate these aspects with tooth mark production. We also discuss the significance and limits of applying these data to fossil assemblages.Goat carcasses were fed to 11 captive individuals. V. komodoensis modifies bone surfaces extensively. Individuals exhibit a “medial-caudal arc'7 when defleshing, followed by inertial swallowing. Bone crushing was not observed. The vast majority of tooth marks are scores, with pits being significantly less common. Tooth furrows and punctures are rare. “Edge marks” are produced on flat elements. Marks are elongate and narrow, with variable lengths and curvature. Over one-third of the marks occur within parallel clusters. Striations are evident on 5% of all marks.Both feeding behavior and tooth marks indicate that ziphodont crowns are ideal for defleshing by being drawn distally through a carcass. Crowns are poorly built for crushing, and within-bone nutrients are acquired through swallowing. Mark production is a by-product of the distal crown movement during the flesh removal process. Scores are the consequence of apical dragging. Edge marks and striated scores result respectively from distal and mesial carinae contact. Mark curvature is the consequence of arcing motions. Parallel clusters may result from repetitive defleshing strokes and/or from multiple crown contacts during a stroke.These observations can be used to draw functional, behavioral, and taphonomic interpretations from fossil assemblages. When they are provisionally applied to theropod tooth marks, similar crown function and defleshing behavior with little bone crushing is apparent. Differences occur concerning mark frequency and curvature, relating potentially to taphonomic biases and rostral motion, respectively.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Sep 1, 1981
Human Predators and Prey Mortality, 2019
Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 1991
The assumption that large mamm al hunting and scavenging are economically advantageous to hominid... more The assumption that large mamm al hunting and scavenging are economically advantageous to hominid foragers is examined in the light of data collected among the Hadza of northern Tanzania. Hadza hunters disregard small prey in favour of larger forms (mean adult mass ≥ 40 kg). Here we report experimental data showing that hunters would reduce their mean rates if they included small animals in the array they target. Still, daily variance in large animal hunting returns is high, and the risk of failure correspondingly great, significantly greater than that associated with small game hunting and trapping. Sharing large kills reduces the risk of meatless days for big game hunters, and obviates the problem of storing large amounts of meat. It may be unavoidable if large carcasses cannot be defended economically against the demands of other consumers. If so, then large prey are common goods. A hunter may gain no consumption advantage from his own big game acquisition efforts. We use Hadza d...
Journal of Archaeological Science, 1993
African Journal of Ecology, Dec 1, 1986
SummaryUnit flesh weights are provided for a sample of wild Thomson's gazelle, Grant's ga... more SummaryUnit flesh weights are provided for a sample of wild Thomson's gazelle, Grant's gazelle, impala and wildebeest. The data permit accurate estimates of the quantity of flesh consumed by modern carnivores and are useful for interpreting skeletal part profiles of archaeological bone assemblages. Despite relative constancy in the percentage of whole carcass flesh (about 50%), there exist differences in the distribution of flesh between sexes (neck v. pelvic‐lumbar regions) and among taxa (forelimb v. hindlimb), but apparently not among age classes.RésuméOn a calculé des unités de poids de chair dans un échantillon composé de gazelles de Thomson et de Grant, d'impalas et de gnous sauvages. Ces données permettent l'estimation de viande consommée par les carnivores actuels et sont utiles pour interpréter les profils squelettiques des assemblages osseux archéologiques. En dépit d'une constance relative dans le pourcentage de chair de la carcasse (environ 50%), il existe entre les sexes des différences dans la répartition de la chair (cou par rapport aux régions pelvique et lombaire) et entre les espèces (membres antérieurs par rapport aux membres postérieurs), mais apparemment pas entre les classes d'âge.
Review of Palaeobotany and Palynology, 2018
Palaeolandscape studies are an essential tool for understanding adaptation and use of plant-and w... more Palaeolandscape studies are an essential tool for understanding adaptation and use of plant-and water-related affordances by hominins. A number of high-resolution palaeolandscape analyses have been carried out at Olduvai Gorge (northern Tanzania) over the last two decades but none have focused on the Tuff ID-IE stratigraphic interval (1.83-1.84 Ma). At locality HWK W this interval presents earthy facies, including siliceous earth, earthy claystone, sandy earth, and earthy sandstone facies varieties, which are rare for Bed I. These facies have been interpreted at other stratigraphic levels to represent densely vegetated wetlands. Additionally, the HWK W site has yielded quantities of fossil bone and tools eroding to the surface. Within the Tuff ID-IE interval, and during regression periods of the Palaeolake Olduvai, fluvial and wetland facies were deposited. During this period, the phytoliths and plant macrofossils show that the vegetation was dominated by palms, associated with a mix of C3 and C4 grasses as well as sedges. The variation in phytolith types within these facies implies a locally diverse palaeoenvironmental micro-mosaic, with stacked transgressive sequences, varying from vegetated fluvial channels to vegetated levées and then backswamp subenvironments. Diatoms are particularly rich at Trench T155 and are associated with sponge spicules, indicating the presence of freshwater palaeowetlands with clear water. The extensive diatom valve fragmentation and the differences among trenches suggest that the diatom depositional environment was a heterogeneous river-fed palaeowetland or a vegetated fluvial channel affected by periodic droughts. A diverse fauna was recovered, comprising autochthonous hippopotamus and crocodile elements as well as herbivores drawn to the freshwater resource. Oldowan lithic artefacts were also recovered and some bone was processed through percussion and cutting by early hominins, likely Homo habilis. Overall, the first landscape reconstruction undertaken at HWK W locality during the Tuff ID-IE interval shows a dynamic and richly vegetated area that would have provided hominins with fresh water, scavengeable carcasses, as well as with edible plant affordances (palm fruits, starch-rich rhizomes from sedges and Typha). The presence of palms suggests the area supported a diversity of trees, affording hominins refuge from predators.
Emerald Publishing Limited eBooks, Aug 11, 2022
Journal of taphonomy, 2003
We argue that the evolutionary significance of prehistoric hominid carnivory will be better appre... more We argue that the evolutionary significance of prehistoric hominid carnivory will be better appreciated if taphonomic tests for evaluating the initial encroachment on the larger carnivoran paleoguild by Oldowan hominids are developed and applied to zooarchaeological assemblages. We propose that the development of taphonomic tests should be guided by three premises: 1) taphonomic measures used to test scenarios of hominid carnivory should be free of interpretive equifinalities; where equifinalities are currently suspected, these must be identified and broken; 2) carnivorans are not a single, homogeneous, taphonomic agent; actualistic research is needed to differentiate the preservable feeding traces of individual carnivore taxa; 3) multiple carnivore species should be assumed to have been involved in creation and modification of bone assemblages; the recognition of the timing and nature of the access of each carnivore to prey carcasses should be sought. We offer some fundamental step...
Journal of Human Evolution, 2016
Labial striations on the anterior teeth have been documented in numerous European pre-Neandertal ... more Labial striations on the anterior teeth have been documented in numerous European pre-Neandertal and Neandertal fossils and serve as evidence for handedness. OH-65, dated at 1.8 mya, shows a concentration of oblique striations on, especially, the left I(1) and right I(1), I(2) and C(1), which signal that it was right-handed. From these patterns we contend that OH-65 was habitually using the right hand, over the left, in manipulating objects during some kind of oral processing. In living humans right-handedness is generally correlated with brain lateralization, although the strength of the association is questioned by some. We propose that as more specimens are found, right-handedness, as seen in living Homo, will most probably be typical of these early hominins.
Pour La Science, 1992
Rappel des theories concernant la pratique de la chasse et du charognage par les hominides. La ne... more Rappel des theories concernant la pratique de la chasse et du charognage par les hominides. La necrophagie et son role evolutif. Caractere favorable aux hominides de la lisiere des forets, salubrite de certaines carcasses, developpement de la sociabilite
Vertebrate Paleobiology and Paleoanthropology, 2009
Human Impacts on Ecosystem Dynamics
This is an open access article under the terms of the Creative Commons Attribution License, which... more This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Quaternary Research, 2002
Lateral variations in whole-rock and clay geochemistry of basal Bed II claystones in Olduvai Gorg... more Lateral variations in whole-rock and clay geochemistry of basal Bed II claystones in Olduvai Gorge, Tanzania, reflect water quality differences across the Eastern Lacustrine Plain ∼1.75 myr ago. Bulk Ba/Sr and (Na2O+K2O+MgO)/Al2O3range from 1.4 to 4.2 and from 0.7 to 1.4, respectively, and indicate leaching of lacustrine claystones beneath freshwater wetlands at times following lake retreat. Bulk MgO/Al2O3(0.3–1.0) and molar Mg/Al (0.5–3.9) ratios of <0.2-μm clays reflect alteration of Mg-rich lacustrine clays. These indicators point to freshest conditions near Locality 43 of Hay (1976; HWK-East; Leakey, 1971), moderate conditions to the east (Locality 40-MCK), and high salinity and alkalinity to the west (Localities 85-VEK, 45-FLK).Clay geochemistry and artifact abundances are well correlated (r=−0.67,p<0.005), suggesting a relationship between paleo-water quality and hominid paleoecology. This pattern is consistent with predictions of greatest artifact discard/loss around fr...
Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 1991
Hominid evolution is marked by very significant increase in relative brain size. Because relative... more Hominid evolution is marked by very significant increase in relative brain size. Because relative brain size has been linked to energetic requirements it is possible to look at the pattern of encephalization as a factor in the evolution of human foraging and dietary strategies. Major expansion of the brain is associated withHomorather than the Hominidae as a whole, and the energetic costs are likely to have forced a prolongation of growth rates and secondary altriciality. It is calculated here that modern human infants have energetic requirements approximately 9% greater than similar size apes due to their large brains. Consideration of energetic costs of brain allow the prediction of growth rates in hominid taxa and an examination of the implications for life-history strategy and foraging behaviour.
Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 1991
New evidence for the tissue types exploited by early hominids from carcasses possibly acquired th... more New evidence for the tissue types exploited by early hominids from carcasses possibly acquired through scavenging is derived from the larger mammal bone assemblages from FLK I, level 22 ( Zinjanthropus floor), and FLKN levels 1 and 2 from Bed I, Olduvai Gorge, Tanzania. Published skeletal part profiles from the two archaeological sites are evaluated using (i) modern observations on the sequence by which carnivores consume carcass parts in order to assess the timing of hominid access to carcasses, and (ii) measurements of flesh and marrow yields to assess the tissue types sought and acquired. These results suggest that the maximization of marrow (fat) yields, not flesh (protein) yields, was the criterion shaping decisions about carcass processing. Because of evidence for density-dependent destruction of some flesh-bearing parts by scavengers of the hominid-butchered assemblages, however, it is uncertain whether carcass parts were transported and acquired by hominids in a largely defl...
Journal of Human Evolution, 1986
The sequence in which nonhuman carnivores consumed the edible parts of 260 larger herbivore carca... more The sequence in which nonhuman carnivores consumed the edible parts of 260 larger herbivore carcasses in the Serengeti region of Tanzania proceeds from (1) hindquarter flesh, to (2) ribcage and forequarter flesh,(3) head flesh,(4) hindlimb marrow,(5) forelimb ...
Uploads
Papers by Robert Blumenschine