9.6: Early Tool Use and Technology

The Early Stone Age (ESA) marks the beginning of recognizable technology made by our human ancestors. Stone-tool (or lithic) technology is defined by the fracturing of rocks and the manufacture of tools through a process called knapping. The Stone Age lasted for more than 3 million years and is broken up into chronological periods called the Early (ESA), Middle (MSA), and Later Stone Ages (LSA). Each period is further broken up into a different techno-complex, a term encompassing multiple assemblages (collections of artifacts) that share similar traits in terms of artifact production and morphology. The ESA spanned the largest technological time period of human innovation from over 3 million years ago to around 300,000 years ago and is associated almost entirely with hominin species prior to modern Homo sapiens. As the ESA advanced, stone tool makers (known as knappers) began to change the ways they detached flakes and eventually were able to shape artifacts into functional tools. These advances in technology go together with the developments in human evolution and cognition, dispersal of populations across the African continent and the world, and climatic changes.

In order to understand the ESA, it is important to consider that not all assemblages are exactly the same within each techno-complex: one can have multiple phases and traditions at different sites (Lombard et al. 2012). However, there is an overarching commonality between them. Within stone tool assemblages, both flakes or cores (the rocks from which flakes are removed) are used as tools. Large Cutting Tools (LCTs) are tools that are shaped to have functional edges. It is important to note that the information presented here is a small fraction of what is known about the ESA, and there are ongoing debates and discoveries within archaeology.

Currently, the oldest-known stone tools, which form the techno-complex the Lomekwian, date to 3.3 mya (Harmand et al. 2015; Toth 1985). They were found at a site called Lomekwi 3 in Kenya. This techno-complex is the most recently defined and pushed back the oldest-known date for lithic technology. There is only one known site thus far and, due to the age of the site, it is associated with species prior to Homo, such as Kenyanthropus platyops. Flakes were produced through indirect percussion, whereby the knappers held a rock and hit it against another rock resting on the ground. The pieces are very chunky and do not display the same fracture patterns seen in later techno-complexes. Lomekwian knappers likely aimed to get a sharp-edged piece on a flake, which would have been functional, although the specific function is currently unknown.

Stone tool use, however, is not only understood through the direct discovery of the tools. Cut marks on fossilized animal bones may illuminate the functionality of stone tools. In one controversial study in 2010, researchers argued that cut marks on a pair of animal bones from Dikika (Ethiopia), dated to 3.4 mya, were from stone tools. The discoverers suggested that they be more securely associated, temporally, with Au. afarensis. However, others have noted that these marks are consistent with teeth marks from crocodiles and other carnivores.

Figure 9.24: Some scholars believe that some genera explored in this chapter were capable of producing more complex stone tools (Oldowan). Credit: Olduwan Industry Chopper 2 by Emmyanne29 is under a CC0 1.0 License.

The Oldowan techno-complex is far more established in the scientific literature (Leakey 1971). It is called the Oldowan because it was originally discovered in Olduvai Gorge, Tanzania, but the oldest assemblage is from Gona in Ethiopia, dated to 2.6 mya (Semaw 2000). The techno-complex is defined as a core and flake industry. Like the Lomekwian, there was an aim to get sharp-edged flakes, but this was achieved through a different production method. Knappers were able to actively hold or manipulate the core being knapped, which they could directly hit using a hammerstone. This technique is known as free-hand percussion, and it demonstrates an understanding of fracture mechanics. It has long been argued that the Oldowan hominins were skillful in tool manufacture.

Because Oldowan knapping requires skill, earlier researchers have attributed these tools to members of our genus, Homo. However, some have argued that these tools are in more direct association with hominins in the genera described in this chapter (Figure 9.24).

Invisible Tool Manufacture and Use

The vast majority of our understanding of these early hominins comes from fossils and reconstructed paleoenvironments. It is only from 3 mya when we can start “looking into their minds” and lifestyles by analyzing their manufacture and use of stone tools. However, the vast majority of tool use in primates (and, one can argue, in humans) is not with durable materials like stone. All of our extant great ape relatives have been observed using sticks, leaves, and other materials for some secondary purpose (to wade across rivers, to “fish” for termites, or to absorb water for drinking). It is possible that the majority of early hominin tool use and manufacture may be invisible to us because of this preservation bias.

Chapter Summary

The fossil record of our earliest hominin relatives has allowed paleoanthropologists to unpack some of the mysteries of our evolution. We now know that traits associated with bipedalism evolved before other “human-like” traits, even though the first hominins were still very capable of arboreal locomotion. We also know that, for much of this time, hominin taxa were diverse in the way they looked and what they ate, and they were widely distributed across the African continent. And we know that the environments in which these hominins lived underwent many changes over this time during several warming and cooling phases.

Yet this knowledge has opened up many new mysteries. We still need to better differentiate some taxa. In addition, there are ongoing debates about why certain traits evolved and what they meant for the extinction of some of our relatives (like the robust australopiths). The capabilities of these early hominins with respect to tool use and manufacture is also still uncertain.

Hominin Species Summaries

Hominin	Sahelanthropus tchadensis
Dates	7 mya to 6 mya
Region(s)	Chad
Famous discoveries	The initial discovery, made in 2001.
Brain size	360 cc average
Dentition	Smaller than in extant great apes; larger and pointier than in humans. Canines worn at the tips.
Cranial features	A short cranial base and a foramen magnum (hole in which the spinal cord enters the cranium) that is more humanlike in positioning; has been argued to indicate upright walking.
Postcranial features	Currently little published postcranial material.
Culture	N/A
Other	The extent to which this hominin was bipedal is currently heavily debated. If so, it would indicate an arboreal bipedal ancestor of hominins, not a knuckle-walker like chimpanzees.

Hominin	Orrorin tugenensis
Dates	6 mya to 5.7 mya
Region(s)	Tugen Hills (Kenya)
Famous discoveries	Original discovery in 2000.
Brain size	N/A
Dentition	Smaller cheek teeth (molars and premolars) than even more recent hominins (i.e., derived), thick enamel, and reduced, but apelike, canines.
Cranial features	Not many found
Postcranial features	Fragmentary leg, arm, and finger bones have been found. Indicates bipedal locomotion.
Culture	Potential toolmaking capability based on hand morphology, but nothing found directly.
Other	This is the earliest species that clearly indicates adaptations for bipedal locomotion.

Hominin	Ardipithecus kadabba
Dates	5.2 mya to 5.8 mya
Region(s)	Middle Awash (Ethiopia)
Famous discoveries	Discovered by Yohannes Haile-Selassie in 1997.
Brain size	N/A
Dentition	Larger hind dentition than in modern chimpanzees. Thick enamel and larger canines than in later hominins.
Cranial features	N/A
Postcranial features	A large hallux (big toe) bone indicates a bipedal “push off.”
Culture	N/A
Other	Faunal evidence indicates a mixed grassland/woodland environment.

Hominin	Ardipithecus ramidus
Dates	4.4 mya
Region(s)	Middle Awash region and Gona (Ethiopia)
Famous discoveries	A partial female skeleton nicknamed “Ardi” (ARA-VP-6/500) (found in 1994).
Brain size	300 cc to 350 cc
Dentition	Little differences between the canines of males and females (small sexual dimorphism).
Cranial features	Midfacial projection, slightly prognathic. Cheekbones less flared and robust than in later hominins.
Postcranial features	Ardi demonstrates a mosaic of ancestral and derived characteristics in the postcrania. For instance, an opposable big toe similar to chimpanzees (i.e., more ancestral), which could have aided in climbing trees effectively. However, the pelvis and hip show that she could walk upright (i.e., it is derived), supporting her hominin status.
Culture	None directly associated
Other	Over 110 specimens from Aramis

Hominin	Australopithecus anamensis
Dates	4.2 mya to 3.8 mya
Region(s)	Turkana region (Kenya); Middle Awash (Ethiopia)
Famous discoveries	A 2019 find from Ethiopia, named MRD.
Brain size	370 cc
Dentition	Relatively large canines compared with more recent Australopithecines.
Cranial features	Projecting cheekbones and ancestral earholes.
Postcranial features	Lower limb bones (tibia and femur) indicate bipedality; arboreal features in upper limb bones (humerus) found.
Culture	N/A
Other	Almost 100 specimens, representing over 20 individuals, have been found to date.

Hominin	Australopithecus afarensis
Dates	3.9 mya to 2.9 mya
Region(s)	Afar Region, Omo, Maka, Fejej, and Belohdelie (Ethiopia); Laetoli (Tanzania); Koobi Fora (Kenya)
Famous discoveries	Lucy (discovery: 1974), Selam (Dikika Child, discovery: 2000), Laetoli Footprints (discovery: 1976).
Brain size	380 cc to 430 cc
Dentition	Reduced canines and molars relative to great apes but larger than in modern humans.
Cranial features	Prognathic face, facial features indicate relatively strong chewing musculature (compared with Homo) but less extreme than in Paranthropus.
Postcranial features	Clear evidence for bipedalism from lower limb postcranial bones. Laetoli Footprints indicate humanlike walking. Dikika Child bones indicate retained ancestral arboreal traits in the postcrania.
Culture	None directly, but close in age and proximity to controversial cut marks at Dikika and early tools in Lomekwi.
Other	Au. afarensis is one of the oldest and most well-known australopithecine species and consists of a large number of fossil remains.

Hominin	Australopithecus bahrelghazali
Dates	3.6 mya
Region(s)	Chad
Famous discoveries	“Abel,” the holotype (discovery: 1995).
Brain size	N/A
Dentition	N/A
Cranial features	N/A
Postcranial features	N/A
Culture	N/A
Other	Arguably within range of variation of Au. afarensis.

Hominin	Australopithecus prometheus
Dates	3.7 mya (debated)
Region(s)	Sterkfontein (South Africa)
Famous discoveries	“Little Foot” (StW 573) (discovery: 1994)
Brain size	408 cc (Little Foot estimate)
Dentition	Heavy anterior dental wear patterns, relatively large anterior dentition and smaller hind dentition, similar to Au. afarensis.
Cranial features	Relatively larger brain size, robust zygomatic arch, and a flatter midface.
Postcranial features	The initial discovery of four ankle bones indicated bipedality.
Culture	N/A
Other	Highly debated new species designation.

Hominin	Australopithecus deyiremada
Dates	3.5 mya to 3.3 mya
Region(s)	Woranso-Mille (Afar region, Ethiopia)
Famous discoveries	First fossil mandible bones were discovered in 2011 in the Afar region of Ethiopia by Yohannes Haile-Selassie.
Brain size	N/A
Dentition	Smaller teeth with thicker enamel than seen in Au. afarensis, with a potentially hardier diet.
Cranial features	Larger mandible and more projecting cheekbones than in Au. afarensis.
Postcranial features	N/A
Culture	N/A
Other	Contested species designation; arguably a member of Au. afarensis.

Hominin	Kenyanthopus platyops
Dates	3.5 mya to 3.2 mya
Region(s)	Lake Turkana (Kenya)
Famous discoveries	KNM–WT 40000 (discovered 1999)
Brain size	Difficult to determine but appears within the range of Australopithecus afarensis.
Dentition	Small molars/dentition (Homo-like characteristic)
Cranial features	Flatter (i.e., orthognathic) face
Postcranial features	N/A
Culture	Some have associated the earliest tool finds from Lomekwi, Kenya, temporally (3.3 mya) and in close geographic proximity to this species/specimen.
Other	Taxonomic placing of this species is quite divided. The discoverers have argued that this species is ancestral to Homo, in particular to Homo ruldolfensis.

Hominin	Australopithecus africanus
Dates	3.3 mya to 2.1 mya
Region(s)	Sterkfontein, Taung, Makapansgat, Gladysvale (South Africa)
Famous discoveries	Taung Child (discovery in 1994), “Mrs. Ples” (discover in 1947), Little Foot (arguable; discovery in 1994).
Brain size	400 cc to 500 cc
Dentition	Smaller teeth (derived) relative to Au. afarensis. Small canines with no diastema.
Cranial features	A rounder skull compared with Au. afarensis in East Africa. A sloping face (ancestral).
Postcranial features	Similar postcranial evidence for bipedal locomotion (derived pelvis) with retained arboreal locomotion, e.g., curved phalanges (fingers), as seen in Au. afarensis.
Culture	None with direct evidence.
Other	A 2015 study noted that the trabecular bone morphology of the hand was consistent with forceful tool manufacture and use, suggesting potential early tool abilities.

Hominin	Australopithecus garhi
Dates	2.5 mya
Region(s)	Middle Awash (Ethiopia)
Famous discoveries	N/A
Brain size	450 cc
Dentition	Larger hind dentition than seen in other gracile Australopithecines.
Cranial features	N/A
Postcranial features	A femur of a fragmentary partial skeleton, argued to belong to Au. garhi, indicates this species may be longer-limbed than Au. afarensis, although still able to move arboreally.
Culture	Crude stone tools resembling Oldowan (described later) have been found in association with Au. garhi.
Other	This species is not well documented or understood and is based on only a few fossil specimens.

Hominin	Paranthropus aethiopicus
Dates	2.7 mya to 2.3 mya
Region(s)	West Turkana (Kenya); Laetoli (Tanzania); Omo River Basin (Ethiopia)
Famous discoveries	The “Black Skull” (KNM–WT 17000) (discovery 1985).
Brain Size	410 cc
Dentition	P. aethiopicus has the shared derived traits of large flat premolars and molars, although few teeth have been found.
Cranial features	Large flaring zygomatic arches for accommodating large chewing muscles (the temporalis muscle), a sagittal crest for increased muscle attachment of the chewing muscles to the skull, and a robust mandible and supraorbital torus (brow ridge).
Postcranial features	A proximal tibia indicates bipedality and similar size to Au. afarensis.
Culture	N/A
Other	The “Black Skull” is so called because of the mineral manganese that stained it black during fossilization.

Hominin	Paranthropus boisei
Dates	2.4 mya to 1.4 mya
Region(s)	Koobi Fora, West Turkana, and Chesowanja (Kenya); Malema-Chiwondo (Malawi), Olduvai Gorge and Peninj (Tanzania); and Omo River basin and Konso (Ethiopia)
Famous discoveries	“Zinj,” or sometimes “Nutcracker Man” (OH5), in 1959 by Mary Leakey. The Peninj mandible from Tanzania, found in 1964 by Kimoya Kimeu.
Brain size	500 cc to 550 cc
Dentition	Very large, flat posterior dentition (largest of all hominins currently known). Much smaller anterior dentition. Very thick dental enamel.
Cranial features	Indications of very large chewing muscles (e.g., flaring zygomatic arches and a large sagittal crest).
Postcranial features	Evidence for high variability and sexual dimorphism, with estimates of males at 1.37 meters tall and females at 1.24 meters.
Culture	Richard Leakey and Bernard Wood have both suggested that P. boisei could have made and used stone tools. Tools dated to 2.5 mya in Ethiopia have been argued to possibly belong to this species.
Other	Despite the cranial features of P. boisei indicating a tough diet of tubers, nuts, and seeds, isotopes indicate a diet high in C4 foods (e.g., grasses, such as sedges). This differs from what is seen in P. robustus.

Hominin	Australopithecus sediba
Dates	1.97 mya
Region(s)	Malapa Fossil Site (South Africa)
Famous discoveries	Karabo (MH1) (discovery in 2008)
Brain size	420 cc to 450 cc
Dentition	Small dentition with Australopithecine cusp-spacing.
Cranial features	Small brain size (Australopithecus-like) but gracile mandible (Homo-like).
Postcranial features	Scientists have interpreted this mixture of traits (such as a robust ankle but evidence for an arch in the foot) as a transitional phase between a body previously adapted to arborealism (tree climbing, particularly in evidence from the bones of the wrist) to one that adapted to bipedal ground walking.
Culture	None of direct association, but some have argued that a modern hand morphology (shorter fingers and a longer thumb) means that adaptations to tool manufacture and use may be present in this species.
Other	It was first discovered through a clavicle bone in 2008 by nine-year-old Matthew Berger, son of paleoanthropologist Lee Berger.

Hominin	Paranthropus robustus
Dates	2.3 mya to 1 mya
Region(s)	Kromdraai B, Swartkrans, Gondolin, Drimolen, and Coopers Cave (South Africa)
Famous discoveries	SK48 (original skull)
Brain size	410 cc to 530 cc
Dentition	Large posterior teeth with thick enamel, consistent with other Robust Australopithecines. Enamel hypoplasia is also common in this species, possibly because of instability in the development of large, thick enameled dentition.
Cranial features	P. robustus features are neither as “hyper-robust” as P. boisei or as ancestral in features as P. aethiopicus. They have been described as less derived, more general features that are shared with both East African species (e.g., the sagittal crest and zygomatic flaring).
Postcranial features	Reconstructions indicate sexual dimorphism.
Culture	N/A
Other	Several of these fossils are fragmentary in nature, distorted, and not well preserved, because they have been recovered from quarry breccia using explosives.