Hunter-gatherer energetics and human obesity

Western lifestyles differ markedly from those of our hunter-gatherer ancestors, and these differences in diet and activity level are often implicated in the global obesity pandemic. However, few physiological data for hunter-gatherer populations are available to test these models of obesity. In this study, we used the doubly-labeled water method to measure total daily energy expenditure (kCal/day) in Hadza hunter-gatherers to test whether foragers expend more energy each day than their Western counterparts. As expected, physical activity level, PAL, was greater among Hadza foragers than among Westerners. Nonetheless, average daily energy expenditure of traditional Hadza foragers was no different than that of Westerners after controlling for body size. The metabolic cost of walking (kcal kg(-1) m(-1)) and resting (kcal kg(-1) s(-1)) were also similar among Hadza and Western groups. The similarity in metabolic rates across a broad range of cultures challenges current models of obesity suggesting that Western lifestyles lead to decreased energy expenditure. We hypothesize that human daily energy expenditure may be an evolved physiological trait largely independent of cultural differences

The Origin of The Acheulean: The 1.7 Million-Year-Old Site of FLK West, Olduvai Gorge (Tanzania)

The appearance of the acheulean is one of the hallmarks of human evolution. It represents the emergence of a complex behavior, expressed in the recurrent manufacture of large-sized tools, with standardized forms, implying more advance forethought and planning by hominins than those required by the precedent Oldowan technology. The earliest known evidence of this technology dates back to c. 1.7 Ma. and is limited to two sites (Kokiselei [Kenya] and Konso [Ethiopia]), both of which lack functionally-associated fauna. The functionality of these earliest Acheulean assemblages remains unknown. Here we present the discovery of another early Acheulean site also dating to c. 1.7 Ma from Olduvai Gorge. This site provides evidence of the earliest steps in developing the Acheulean technology and is the oldest acheulean site in which stone tools occur spatially and functionally associated with the exploitation of fauna. Simple and elaborate large-cutting tools (LCT) and bifacial handaxes co-exist at FLK West, showing that complex cognition was present from the earliest stages of the acheulean. Here we provide a detailed technological study and evidence of the use of these tools on the butchery and consumption of fauna, probably by early Homo erectus sensu lato

Humboldt Lab Tanzania

In den Depots des Ethnologischen Museums Berlin befinden sich bis heute zahlreiche Objekte, die von der deutschen Kolonialmacht zwischen 1885 und 1918 in Tansania erbeutet wurden. In dem Projekt „Humboldt Lab Tanzania“ setzten sich tansanische und deutsche Wissenschaftler_innen, Kurator_innen und Künstler_innen kritisch mit einer Auswahl von Objekten auseinander.Until today there are numerous objects in the storage of the Ethnologisches Museum Berlin which have been appropriated by the colonial power of former German East Africa between 1885 and 1918. The project “Humboldt Lab Tanzania” joins Tanzanian and German researchers, curators, and artists who critically discuss chosen artefacts

Ancient DNA and deep population structure in sub-Saharan African foragers

Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa(1-4). Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations(3,5). Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80-20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch. DNA analysis of 6 individuals from eastern and south-central Africa spanning the past approximately 18,000 years, and of 28 previously published ancient individuals, provides genetic evidence supporting hypotheses of increasing regionalization at the end of the Pleistocene.info:eu-repo/semantics/publishedVersio

Sedimentary geology and human origins: A fresh look at Olduvai Gorge, Tanzania

ABSTRACT: Recent field work at Olduvai Gorge (Tanzania) using sedimentary geology, in particular high-resolution paleoenvironmental reconstruction and isotope geochemistry, has revealed that freshwater was in proximity to a number of the rich fossil sites in Beds I and II (, 2.0-1.0 Ma). This paper presents the first geological evidence for springs associated with archaeological sites in this semiarid rift basin. The springs appear to be limited to a small area within the basin and were likely connected to faults that acted as conduits for groundwater. Tufas associated with ten archaeological sites have stable-isotope signatures occurring in a cluster bounded by d 18 O ratios from 26% to +1%, and the d 13 C ratios from 25% to +2%. The d 18 O values cluster around 24%, that of precipitation in the region, indicating a meteoric source. The longevity of the spring record reflects a hydrologic system that apparently persisted for hundreds of thousands of years. Previous landscape reconstructions depicted the archaeological sites on the lake margin of paleo Lake Olduvai, as an alkaline playa. The discovery of springs at or near the archaeological sites provides fresh insights for interpreting hominin behavior during this key time in evolution with respect to procuring food, water, and materials for stone tools

Supplementary Figure from Chronotype variation drives night-time sentinel-like behaviour in hunter-gatherers

Epoch-by-epoch illustration of number of awake individuals during the nighttime perio

Methods Supplementary Table from Chronotype variation drives night-time sentinel-like behaviour in hunter-gatherers

Summary statistics for epoch-by-epoch (minute-by-minute) analysis of sleep-wake pattern

Phytoliths infer locally dense and heterogeneous paleovegetation at FLK North and surrounding localities during upper Bed I time, Olduvai Gorge, Tanzania

International audienceThe phytolith content of 10 samples collected immediately under Tuff IF (similar to 1.785 Ma) at FLK N and other surrounding localities (similar to 2 km(2)) provides a direct botanical evidence for woody vegetation in the eastern margin of Olduvai Gorge during uppermost Bed I time. Observation and counting of 143 phytolith types (5 to > 150 mu) reveal dense but heterogeneous woody cover (similar to 40-90%) of unidentified trees and/or shrubs and palms associated to the freshwater springs surrounding FLK N, and more open formation (presumably similar to 25-70% woody cover) in the southeast at localities VEK, HWK W and HWK E. The paleovegetation is best described as groundwater palm forest/woodland or bushland, which current analogue may be found near Lake Manyara in similar hydrogeological context (freshwater springs near saline/alkaline lake). Re-evaluating the published pollen data based on this analogy shows that 70% of the pollen signal at FLK N may be attributed to thicket-woodland, Acacia groundwater woodland, gallery and groundwater forests; while <30% is attributed to swamp herbage and grasslands. Micro-botanical, isotopic, and taphonomical studies of faunal remains converge on the same conclusion that the area surrounding FLK N, which attracted both carnivores and hominins in the early Pleistocene, was densely wooded during uppermost Bed I time

Paleoenvironmental and paleoecological reconstruction of a freshwater oasis in savannah grassland at FLK North, Olduvai Gorge, Tanzania

International audienceThe records of early hominins are commonly localized both temporally and spatially even in archaeologically rich basins like Olduvai Gorge, Tanzania, The FLK North site was discovered in 1960, but the reason for the exact location of this dense concentration of fossils and stone tools on a lake-margin flat has not been explained. We present new geological and geochemical information from six excavations in upper Bed which revealed up to 1.4-m-thick carbonate deposits, attesting to the presence of freshwater springs in the area surrounding FLK North. The delta O-18 signatures of the tufa are typical for meteoric water that has evolved during evaporation. Tuff IF that caps the sequence was deposited on uneven topography with the highest area a low-relief ridge between two faults at the archaeological site and lowest areas being sites of groundwater discharge. The model proposed here is that rainfall on adjacent highlands was transported to the basin where faults acted as conduits for water. Similar hydrogeological settings at modern lakes Manyara and Eyasi, currently support lush groundwater forest and woodland despite arid climate. FLK North may have been an "oasis" offering freshwater and shelter for consuming meat by both carnivores and hominins

A spring and wooded habitat at FLK Zinj and their relevance to origins of human behavior

International audienceThe 1959 discovery of the hominin fossil Zinjanthropus boisei brought the world's attention to the rich records at Olduvai Gorge, Tanzania. Subsequent excavations of archaeological level 22 (FLK Zinj) Bed I uncovered remains of Homo habilis and a high-density collection of fossils and Oldowan stone tools. The occurrence of this unusual collection of bones and tools at this specific location has been controversial for decades. We present paleoecological data that provide new insights into the origin of FLK Zinj. Our recent excavations 200 m north of the site uncovered a 0.5-m-thick tufa mound draped by Tuff IC, in the same stratigraphic horizon as level 22. Stable isotope analyses indicate that the carbonates were deposited by a freshwater spring. Phytolith analysis of the waxy clay under Tuff IC revealed abundant woody dicotyledon and palm phytoliths, indicating that the site was wooded to densely wooded. The time equivalency and close physical proximity of the two environments indicate the two are related. This study has provided the first documented evidence of springs in Bed land these data have important implications for the interpretation of hominin behavior in meat acquisition and the ongoing debate on scavenging versus hunting