New excavations at the FLKZinjanthropussite and its surrounding landscape and their behavioral implications

Abstract

International audienceRenewed excavations at FLK Zinj and its surrounding landscape have yielded valuable information regarding its paleoecological situation and the prehistoric behavioral function of the site. The density of materials at the main cluster of the site excavated by Leakey contrasts with the bone and lithic scatters surrounding the site. The location of FLK Zinj, situated a few hundred meters away from a freshwater spring, would have enabled hominins access to water, plants and game. The appeal of the spot for hominins (also explained by the presence of a wooded habitat) is confirmed by inferences of its redundant use prior and during the formation of the FLK Zinj paleosol, as witnessed by materials accumulated both under and on the waxy clay deposit that constitutes the FLK Zinj stratum. The single-cluster nature of the site indicates central-place behavior and evidence is provided that hominins occupied the site at a time of very low predation hazards in the area

Dietary options and behavior suggested by plant biomarker evidence in an early human habitat

“…1). Recent excavations (18)(19)(20)(21) Fig. 1D) exposed a traceable thin (5-50 cm), waxy green to olive-brown clay horizon developed by pedogenic alterations of playa lake margin alluvium (22).…”

“…To date, craniodental remains from at least three hominin individuals (18)(19)(20), including preadolescent early Homo and Paranthropus boisei, were recovered from FLK Zinj. Fossils and artifacts embedded in the paleosol horizon often protrude into an overlying airfall tuff (18,19), which suggests fossil remains were catastrophically buried in situ under volcanic ash. Rapid burial likely fostered the exceptional preservation of both macrofossils (10) (Fig.…”

“…0.05) occurs within 5 km of either forest or standing freshwater (35). Given a paucity of shaded refuge and potable water in the catchment, the concentration of hominin butchery debris (18)(19)(20)(21) exclusively within the forest microhabitat and adjacent to a freshwater wetland (Fig. 4) is notable.…”

The FLK Zinj paleolandscape: Reconstruction of a 1.84 Ma wooded habitat in the FLK Zinj-AMK-PTK-DS archaeological complex, Middle Bed I (Olduvai Gorge, Tanzania)

“…FLK Zinj is important for understanding early hominin behavior, the interpretation of which is still a matter of debate since Leakey (1971) suggested that the site was a "living floor". The abundance of skull and limb bones has been interpreted, so far, in two different ways (Domínguez-Rodrigo et al, 2007): a) hominins carried selected parts from fleshed carcasses to the site, and hence were most likely hunters (Bunn and Kroll, 1986;Domínguez-Rodrigo, 2002;Domínguez-Rodrigo and Pickering, 2003;Domínguez-Rodrigo, 1997;Oliver, 1994;Rose and Marshall, 1996); b) hominins transported selected skeletal parts from partially defleshed carcasses (Blumenschine, 1995;Capaldo, 1997), or completely defleshed carcasses, which implied the scavenging of brain and marrow-bearing long limb bones from prey found at felid kills (Blumenschine, 1995(Blumenschine, , 1991. The former interpretation is currently widely supported by taphonomic research (e.g.…”

“…Bovid ecomorphology later showed a significant proportion of intermediate and closed habitats (Bishop, 1994;Kappelman et al, 1997;Plummer and Bishop, 1994). Phytolith analyses of samples from FLK Zinj level 22 and contemporaneous paleosols in surrounding areas (~2 ha) reconstructed a densely wooded environment near a freshwater spring (Ashley et al, 2010a). δ 13 C values for sedimentary leaf lipids and total organic carbon also indicated recurrent ecosystem variations, where open C 4 grasslands abruptly transitioned to closed C 3 forests within several hundreds to thousands of years (Magill et al 2013a) in response to varying precipitation (Magill et al, 2013b).…”