Temporal span of bone accumulations at Olduvai Gorge and implications for early hominid foraging behavior

Paleobiology ◽  
1986 ◽  
Vol 12 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Richard Potts
Keyword(s):  
Long Bone ◽  
Olduvai Gorge ◽  
Short Term ◽  
Early Hominid ◽  
Hunter Gatherers ◽  
Faunal Assemblages ◽  
Subaerial Exposure ◽  
Early Hominids ◽  
Animal Bones ◽  
Spotted Hyenas

Bones of mammals exhibit progressive stages of weathering during their time of subaerial exposure. Consequently, the study of bone weathering in fossil assemblages may help to assess the period represented by an accumulation of bones. Stages of bone decomposition due to subaerial weathering have been identified in assemblages of fossil macromammals from Olduvai Gorge, Tanzania. A modern bone assemblage collected by spotted hyenas is used to devise a method for recognizing attritional accumulations of bones from weathering characteristics. This method, which involves study of long bone diaphyses, is applied to Plio-Pleistocene faunal assemblages from Olduvai, 1.70–1.85 ma old. Previous work indicates that early hominids had an important role in the collection of fauna at five of the six sites studied. It is shown that animal bones were accumulated at each site over a period of probably 5–10 yr or more. The length of this period, along with other taphonomic evidence, suggests that the processes of bone aggregation at these sites differed from those at the short-term campsites of modern, tropical hunter-gatherers.

Wetland Diagenesis and Traces of Early Hominids, Olduvai Gorge, Tanzania

2002 ◽  
Vol 57 (2) ◽  
pp. 271-281 ◽  
Author(s):  
Daniel M. Deocampo ◽  
Robert J. Blumenschine ◽  
Gail M. Ashley
Keyword(s):  
Water Quality ◽  
Freshwater Wetlands ◽  
Olduvai Gorge ◽  
Early Hominid ◽  
Early Hominids ◽  
Early Stone Age ◽  
Land Use Models ◽  
Landscape Scales ◽  
First Time ◽  
Lateral Variations

AbstractLateral 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)/Al2O3 range 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 freshwater sources where scavanging opportunities were greatest for hominids. This quantifies a relationship between artifact density distribution and a paleoecological proxy over landscape scales for the first time in Early Stone Age archaeology. In contrast, fossil bone abundance is uncorrelated (r=0.14, p=0.6), reflecting more complex taphonomic processes. Quantitative tests of landscape-scale land-use models are important for understanding early hominid behavior and its evolution.

Hominid carnivory and foraging strategies, and the socio-economic function of early archaeological sites

1991 ◽  
Vol 334 (1270) ◽  
pp. 211-221 ◽  
Keyword(s):  
Predation Risk ◽  
Foraging Strategies ◽  
Archaeological Sites ◽  
Olduvai Gorge ◽  
Marrow Fat ◽  
Density Dependent ◽  
Early Hominids ◽  
Competing Hypotheses ◽  
New Evidence ◽  
Economic Function

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 defleshed condition. The results on tissue types acquired are combined with a discussion of predation risk, feeding competition and the equipment needs of carcass processing in an attempt to identify archaeological test implications of competing hypotheses for the socio-economic function of the earliest archaeological sites.

A Temporal Hierarchy of Paleoecologic Processes Within a Middle Devonian Epeiric Sea

1990 ◽  
Vol 5 ◽  
pp. 178-209 ◽  
Author(s):  
Carlton E. Brett ◽  
Keith B. Miller ◽  
Gordon C. Baird
Keyword(s):  
Temporal Change ◽  
Explanatory Models ◽  
Temporal Scale ◽  
Short Term ◽  
Faunal Assemblages ◽  
Faunal Change ◽  
Wide Range ◽  
Ecological Theories ◽  
Stratigraphic Record ◽  
Underlying Processes

Among the most intriguing and significant aspects of the marine stratigraphic record are patterns of temporal change in fossil assemblages and paleocommunities. Understanding the stratigraphic patterns and the correct temporal scale of such faunal change is crucial to interpreting the underlying processes involved. Inattention to the temporal scale at which paleontological data are collected, and at which faunal change is observed, often results in the use of entirely inappropriate explanatory models. In many cases modern ecological theories have been misapplied to the fossil record because problems of scale were not adequately considered. The term “community” itself has been applied to such a wide range of fossil accumulations that it has ceased to have any consistent paleoecologic meaning (see discussion in Järvinen et al.,1986). For this reason, we prefer to use the term “assemblage” for time-averaged accumulations of fossils, and restrict “community” to only those organisms which actually lived together in the same space and time (i.e., a biocoenosis). Therefore, faunal assemblages, even when untransported, are the preserved amalgamated record of many successive communities within which short-term (10 – 100 years) changes may or may not be resolvable. Recurrent, compositionally similar assemblages, believed to have occupied generally similar benthic environments, are then grouped into biofacies which can be seen to intergrade and migrate through time.

One Person's Food: How and Why Fish Avoidance May Affect the Settlement and Subsistence Patterns of Hunter-Gatherers

2001 ◽  
Vol 66 (1) ◽  
pp. 141-161 ◽  
Author(s):  
M. E. Malainey ◽  
R. Przybylski ◽  
B. L. Sherriff
Keyword(s):  
Foraging Strategies ◽  
Western Canada ◽  
Large Mammals ◽  
Archaeological Remains ◽  
Hunter Gatherers ◽  
Faunal Assemblages ◽  
Fat Malabsorption ◽  
Winter Grazing ◽  
Fish Avoidance ◽  
Newborn Animals

Foraging strategies of modern hunter-gatherers may not accurately model resource use of specialized big-game hunters. Historic accounts from the Northern Plains of North America indicate that utilization of spring-spawning fish when large mammals were fat-depleted was not universally beneficial. Three independent reports from Europeans and Americans show that a sudden switch from a prolonged diet of lean red meat to fish produces symptoms consistent with lipid (fat) malabsorption. It is hypothesized that plains-adapted hunter-gatherers formed their camps in grassland environments and hunted big game throughout the winter The effects of eating lean meat alone were avoided by utilizing fetal and newborn animals and through the use of stored carbohydrate-rich foods. Groups associated with wooded environments wintered along the margins of the winter grazing range. They followed a diverse strategy with opportunistic use of big game and were able to exploit spring-spawning fish. Archaeological remains from 18 sites from the plains, parkland, and forests of Western Canada were used to test these hypotheses. The faunal assemblages, tools, and identifications of lipid residues from pottery vessels were consistent with the proposed strategies.

Animal Bones from Caves to Cities: Reverse Utility Curves as Methodological Artifacts

1997 ◽  
Vol 62 (4) ◽  
pp. 698-711 ◽  
Author(s):  
Curtis W. Marean ◽  
Carol J. Frey
Keyword(s):  
Iron Age ◽  
Positive Relationship ◽  
Mechanistic Explanation ◽  
Long Bone ◽  
Element Abundance ◽  
Long Bones ◽  
Skeletal Element ◽  
Economic Decisions ◽  
Abundance Estimates ◽  
Animal Bones

Utility-based studies are attractive to zooarchaeologists because they afford the opportunity of investigating economic decisions relative to particular contexts. While a positive relationship between utility and skeletal element abundance is anticipated at residential sites, a reverse utility curve is most common. A popular mechanistic explanation argues that reverse utility curves result from density-mediated destruction of bone, suggesting that utility-based studies will rarely be successful as density-mediated destruction will overwhelm any skeletal element patterning created by differential transport. We show with archaeological and experimental/naturalistic taphonomic data that the mechanistic explanation is overstated. Fauna from Kobeh cave (a Mousterian site) and "Ain Dara (an Iron Age site) both show a reverse utility pattern when estimates of long bone abundance are based just on ends (the procedure followed at all sites that have shown a reverse utility pattern), and all bones are plotted together. When long bone abundance is estimated from the middle shaft portion, the reverse utility pattern collapses and a positive relationship arises. The ubiquity of the reverse utility curve derives in many cases from basing long bone abundance estimates on ends and scatter-plotting the abundance of long bones with non-long bones, thus restricting the analysis to the least dense most spongy bone portions. Long bone abundance estimates must include the middle shaft portion to attain accurate estimates of element abundance. Long bone abundance, when based on shaft portions, can be usefully compared to utility to investigate utility-based models of human behavior.

scholarly journals Analysis of short-term treatment with the phosphodiesterase type 5 inhibitor tadalafil on long bone development in young rats

2018 ◽  
Vol 315 (4) ◽  
pp. E446-E453 ◽  
Author(s):  
Luqiang Wang ◽  
Haoruo Jia ◽  
Robert J. Tower ◽  
Michael A. Levine ◽  
Ling Qin
Keyword(s):  
Growth Plate ◽  
Time Course ◽  
Bone Growth ◽  
Bone Structure ◽  
Primary Cultures ◽  
Long Bone ◽  
Short Term ◽  
Short Term Treatment ◽  
Bone Properties ◽  
Phosphodiesterase Type 5 Inhibitor

Cyclic GMP (cGMP) is an important intracellular regulator of endochondral bone growth and skeletal remodeling. Tadalafil, an inhibitor of the phosphodiesterase (PDE) type 5 (PDE5) that specifically hydrolyzes cGMP, is increasingly used to treat children with pulmonary arterial hypertension (PAH), but the effect of tadalafil on bone growth and strength has not been previously investigated. In this study, we first analyzed the expression of transcripts encoding PDEs in primary cultures of chondrocytes from newborn rat epiphyses. We detected robust expression of PDE5 as the major phosphodiesterase hydrolyzing cGMP. Time-course experiments showed that C-type natriuretic peptide increased intracellular levels of cGMP in primary chondrocytes with a peak at 2 min, and in the presence of tadalafil the peak level of intracellular cGMP was 37% greater ( P < 0.01) and the decline was significantly attenuated. Next, we treated 1-mo-old Sprague Dawley rats with vehicle or tadalafil for 3 wk. Although 10 mg·kg−1·day−1 tadalafil led to a significant 52% ( P < 0.01) increase in tissue levels of cGMP and a 9% reduction ( P < 0.01) in bodyweight gain, it did not alter long bone length, cortical or trabecular bone properties, and histological features. In conclusion, our results indicate that PDE5 is highly expressed in growth plate chondrocytes, and short-term tadalafil treatment of growing rats at doses comparable to those used in children with PAH has neither obvious beneficial effect on long bone growth nor any observable adverse effect on growth plate structure and trabecular and cortical bone structure.

scholarly journals Effect of short-term subaerial exposure on the cauliflower coral, Pocillopora damicornis, during a simulated extreme low-tide event

Coral Reefs ◽  
2017 ◽  
Vol 36 (2) ◽  
pp. 401-414 ◽  
Author(s):  
Ana Lucia Castrillón-Cifuentes ◽  
Diego F. Lozano-Cortés ◽  
Fernando A. Zapata
Keyword(s):  
Pocillopora Damicornis ◽  
Short Term ◽  
Subaerial Exposure

Intrasite Spatial Analysis of Bone: Subtracting the Effect of Secondary Carnivore Consumers

1994 ◽  
Vol 59 (4) ◽  
pp. 748-768 ◽  
Author(s):  
Curtis W. Marean ◽  
Leanne Bertino
Keyword(s):  
Spatial Analysis ◽  
Human Behavior ◽  
Experimental Studies ◽  
Archaeological Site ◽  
Original Position ◽  
Limb Bone ◽  
Limb Bones ◽  
Animal Bones ◽  
Spotted Hyenas ◽  
Bone Fragments

Animal bones discarded by people are commonly subject to disturbance by carnivores. These carnivores are present throughout the world and include wolves, coyotes, hyenas, and many others. This disturbance not only modifies and destroys bone, but also moves many of the bone fragments away from their original position of discard. Intrasite spatial analyses of bone that seek patterns meaningful to human behavior thus need to subtract the effect of carnivore disturbance. Experimental studies with spotted hyenas show that the position of a bone fragment on a limb bone, combined with bone surface modification, can be used to identify a class of bone fragments that are minimally affected by carnivores and are thus the best indicators of spatial patterning resulting from human behavior. Limb-bone ends are moved significant distances, as are shaft fragments as a general class. However, middle-shaft portions of limb bones that preserve percussion marks from hammerstone breakage retain nearly the precise spatial position as originally discarded by hominids. Thus, any spatial analysis of bone, when carnivores are implicated as contributors or consumers at an archaeological site, should focus on middle-shaft portions of limb bones with percussion marks.

Sign in / Sign up

Export Citation Format

Share Document