Klasies River Caves

Klasies River Cave is located on the border of the Tsitsikamma mountain range on the southeastern coast of Africa. The site sits within the Greater Cape Floristic region, characterized by the fynbos biome; however the Klasies River Cave environment is mixed woods and shrubby brushland and maintains a temperate climate. Klasies River main site is located on a sandstone cliff less than 1 kilometer from the Klasies River mouth and on the coast of the Indian Ocean. The district receives approximately 500–700 mm (20–28 in) of rainfall annually. The site consists of Caves 1 and 2, and the protected overhangs of Cave 1A and 1B, together known as Klasies River main site. However, Cave 2 was not accessible until later stages after there had been significant deposition and build-up of sediments, and Cave 1B has been under-documented; most finds therefore come from Caves 1 and1A. == Excavations ==

From 1967–1968 John Wymer and Ronald Singer conducted excavations that revealed evidence of Middle Stone Age (MSA)-associated human habitation beginning approximately 125,000 years ago. == Paleoenvironment ==

Paleoenvironment reconstruction uses multiple analytical foci to help determine a proximate estimate of the climate of a site during a given time frame. These reconstructions are aided through archaeological excavations and finds. Analysis of faunal remains can indicate what species existed across space and time. Likewise, archaeobotanical analysis provides insight into the plants that were in proximity to the site. These determinations are also aided by global climate estimates provided by deep sea cores. Plant and animal remains can also be indicative of certain climates as species have certain climatic ranges and preferred biomes. Changes in the location of the sea shore and in the grassy or wetland areas surrounding the cave have been determined using these methods. MSA I fauna indicate a mosaic environment that included closed, drier areas with micromammals including moles, and open grasslands that favored grazing ungulates. Current ethnobotanical research exploring the biodiversity of Klasies River and the Cape region found that many hunter-gatherer-pastoralists from the Khoi and San populations use the flora and fauna of the region that was also found in archaeobotanical and faunal assemblages. The study took an inventory of plants within 5 km of the modern Klasies site and discovered 268 species. Over 50% of these plants were medicinal and 43% were edible or had other uses as demonstrated from interviews with Khoi and San communities. While not all of these plant species may have existed during the Middle Stone Age, these findings still demonstrate the longevity of plant knowledge throughout the communities in the area. The study also noted that the use of certain plant types for survival during climate changes, and proposed that humans in the past could have subsisted in similar ways. == Findings ==

Material culture There is evidence for stone tool production at the site. Rounded quartzite cobbles appear to be the preferred material for stone tool production based on the recovery of raw materials at the site. Tools from MSA III are made from more non-local raw materials than MSA I or II, but less than Howiesons Poort; these tools from MSA III also have a similar core morphology to Howiesons Poort. The MSA IV lithics consist of more flake blades than observed in MSA III. Three denticulated bone tools Instead, the authors found starchy reside within the teeth of the rasp and suggest that the tool was used for plant processing rather than as an instrument or skin abrader, however this is not proven. Use-wear analysis found longitudinal striations consistent with longitudinal action (including arrow use); microstriations suggest that the bone point was also hafted within a reed, consistent with ethno-historic accounts of early hunter-gatherers from the region. Alternative interpretations that include use as a domestic tool for woodworking or as a javelin point are not consistent with microwear of the bone point leading the authors to conclude that the bone tool was used as an arrowhead. Researchers have also confirmed evidence of shell beads at Klasies River caves, which is corroborated by similar discoveries from other cave sites on the southern coast. Plants within a 12.5 kilometer foraging radius of the caves would have included 161 native species from a mix of geophytes / underground storage organs (USOs), leaves, and fruits, all of which would provide sufficient nutrients for the hominins at the site. By increasing the foraging radius to 35 kilometers away from the site, more nuts, seeds, and grains become available with a total of 281 available edible plant species; these resources were less abundant within the smaller radius and would give reason for an extended foraging journey to acquire varied and less perishable nutrients. A majority of the food plants within these radii can be eaten raw. The association of animal and plant remains with hearths provides evidence that hominins at the site used fire to cook. Bones with cut marks and percussion marks from hammer stones indicate that meat and bone marrow were consumed. Cooked foods provide quickly digestible energy and would have contributed to a higher quality diet which could lead to an evolutionary change in Homo sapiens. Samples taken from hearths within MSA I and Howiesons Poort levels identified parenchyma, heated bones and shellfish found together indicating the cooking of multiple food sources. The parenchyma samples came from underground storage organs, but preservation did not allow for determination of plant species. The abundance of plant species available year-round, as discussed in previous sections, would have provided many reliable energy sources for humans; cooking these starchy plants increases energy absorption. Site occupation patterns based on faunal, food source remains, and lithic evidence suggest that hominins were more mobile during the MSA I than in MSA II as indicated by use-wear analysis on stone tools and interpretation of shell middens. == Human remains ==

During the first excavation in 1967 by Singer and Wymer, a coarse sieve was used for screening causing the loss of smaller bones, shells, and other artifacts; because of this sample sized are biased because long bones (i.e. bone shafts) and small bones (i.e. finger bones) were not collected. However, the bones that were analyzed show anatomical differentiation within Homo sapiens throughout time. Inventory The human remains from KRM are mostly fragmentary adult skeletal elements. No human remains were recovered from the WS member (MIS IV). Only one deciduous tooth is attributable to Howiesons Poort levels (Upper Member). The Upper member (MSA III) contains two parietal fragments, 1 deciduous tooth, and one permanent premolar. Of the remains recovered, two mandibles display the idiopathic dental anomaly of hypercementosis; this condition has been discovered in Neanderthal and Homo erectus remains, but the individuals at Klasies remain the oldest case of hypercementosis in Sub-Saharan Africa (ca. 119 ka). This find is significant because it demonstrates continuity of the condition through the hominin lineage. Ancestral and derived traits vary with genetic drift, mutations, and other genetic factors that can steer evolution in many directions. For further discussion on human evolution, see human evolution, evolutionary genetics, and timeline of human evolution. Anatomically modern humans share traits with today's modern Homo sapiens. Remains from the Klasies site appear to have modern human morphology based on cranial traits. The specimens do not have retromolar spaces in the mandible and the supraorbital regions appear similar to other Homo sapiens specimens. engraved ochre and beads at Blombos Cave, bone tool culture at Sibudu Cave, and incised ostrich eggshells from Diepkloof rock shelter have all been interpreted as complex behaviors. The debate about the origin of modern human behavior originally began as an assumption that modern anatomy and modern behavior came as a package during the Upper Paleolithic, but the previously discussed evidence situates the debate in the Middle Stone Age as an early adaptation that accrued slowly over time. At Klasies River, the lithic techno-complexes are indicative of symbolic behavior as they change through the sequence from MSA I through MSA III. Each sequence displays a different social convention for construction of stone tools (a techno-complex) that isn't based on raw material availability. However, Howiesons Poort is the only recognized techno-complex at Klasies River Caves because it is recognized as a techno-complex across Southern Africa; further studies may recognize techno-complexes from other culture-stratigraphies as well. Conventionalized artifact manufacture that is passed through generations is argued as symbolic behavior by Sarah Wurz, the current primary investigator at the site. KRM's bone tools represent this symbolic behavior as they exhibit similar modifications and use-wear patterns that suggest they were used and created in the same way. Use of ochre is sometimes interpreted as symbolic behavior, however it also has practical purposes for paint or as an element of an adhesive. At KRM higher concentrations of red ochre are found in the MSA I and Howiesons Poort levels which may be evidence of ritual or symbolic use. Despite the evidence above, modern human behavioral models are still a contested issue. Arguments for origins of behavioral modernity rely on findings of hominin remains at prehistoric sites; this allows material culture and inferred behaviors to be correlated with the discovered remains. However, taphonomic processes produce a bias towards sites where there is good preservation, skewing results and potentially obscuring the origin of behavioral modernity. Other studies that assert behavioral modernity rely on variables like climate, resource availability, and labor, which also influence behavior. Arguments that state brain size, social demographics and other factors are the cause of behavioral modernity are undermined by these outside variables. Complex behaviors include language and symbolic objects, which are not easily found in the archaeological record; however exchange networks, alliances, and egalitarianism are also indicators of complex behavior. == Related sites ==

• Related Southern Africa Middle Stone Age sites: Border Cave, Blombas Cave, Sibudu Cave, Diepkloof Rock Shelter, Die Kelders, Boomplaas Cave • Sites with fossil Homo sapiens: Jebel Irhoud, Omo Kibish, Herto remains General: • List of fossil sites (with link directory) • List of hominin (hominid) fossils (with images) • List of archaeological periods • List of caves in South Africa ==References==