Toolmakers

Question 1

What type of tool are the oldest we have discovered?

Where/ when are they from

Answer 1

Lomekwian

lithic artifacts found at Lomekwi (Kenya) dated to 3.3 Ma.

Question 2

Describe Lomekwian lithic artifacts

What can they be compared to

Answer 2

anvils, cores (about 3.4 kg) and flakes, made of basalt and phonolite, series of adjacent and superposed unidirectional flakes detached.

• Similar to the non-human primate hammer-on-anvil techniques when engage in nut cracking.

Harmand (2015) argued that these were closer to apes nut cracking tools

Question 3

Based upon chronology, which hominins could have made the Lomekwian artifacts ?

Which species specifically? When and where did they exist?

Answer 3

Taxonomical context based on the chronology: Australopithecus and Kenyanthropus.

A. deyiremeda in Ethiopia
(3.6-3.3 Ma)

A. afarensis in
Ethiopia, Kenya and Tanzania
(3.9-2.9 Ma)

K. platyops in Kenya(3.7-3.4 Ma)

(no Homo)

Question 4

Have any hominin remains been found near the site where Lomekwian tools were discovered?

Answer 4

Dental remains from Lomekwi (but not in association): 67 teeth, size overlaps with A. afarensis and A. deyiremeda, dated to 3.5-3.3 Ma

KNM-WT 8556
(Skinner et al., 2020)

Question 5

Why is there some controversy regarding Lomekwian tools as the oldest fossils?

Answer 5

 Some suggest Lomekwi tools are not created by hominins at all but in fact just rocks that were shaped by random surface occurrences

Question 6

If not Lomekwi, where are the oldest tools found?

Answer 6

Lithic artefacts at Gona (Ethiopia) dated to 2.6 Ma.

Question 7

Describe the oldest tools that have been found in Gona, Ethiopia?

Answer 7

Oldowan (2.8-1.7 Ma): chopping tools and flakes, made of quartz, quartzite or
basalt, chipped in two directions.

Question 8

Which hominins could have created the oldest tools at Gona

Answer 8

Taxonomical context based on the chronology: early Homo and Paranthropus.

P. aethiopicus in
Ethiopia (2.7-2.2 Ma)
early Homo at 2.8 Ma in Ethiopia
(Villmoare et al., 2015)

Question 9

What are the oldest cut marks found on bones?

Why is this important?

Answer 9

Cut-marks at Dikika (Ethiopia) dated to >3.4 Ma.

• Evidence of stone-tool-assisted consumption of meat: flesh removed from bones, percussion marks that prove access to marrow

Question 10

What were the specific marks found on 3.4Ma bones in Dikika

Who could’ve made these marks?

Answer 10

cut-marked rib
(McPherron et al., 2010)

percussion marks on a femur shaft
(McPherron et al., 2010)

Taxonomical context based on the chronology: Australopithecus and Kenyanthropus:
A. deyiremeda in Ethiopia
(3.6-3.3 Ma)
A. afarensis in
Ethiopia, Kenya and Tanzania
(3.9-2.9 Ma)
K. platyops in Kenya
(3.7-3.4 Ma)

Question 11

Other than Dikika, what are the oldest cut marks on bones?

Answer 11

Cut-marks at Gona (Ethiopia) dated to 2.5 Ma.
• Evidence of stone-tool-assisted consumption of meat: carcasses eviscerated,
upper and intermediate limb bones of ungulates defleshed.
• Behaviour: primary access to the carcasses?

suggested to show no other carnivore had access to the meat before hominins (Domínguez-Rodrigo et al., 2005)

Question 12

Who was at Gona who could have caused the cut marks on the bones 2.5mya

Answer 12

P. aethiopicus in
Ethiopia (2.7-2.2 Ma)

early Homo at 2.8 Ma in Ethiopia
(Villmoare et al., 2015)

Question 13

How can we assess which areas of the brain are needed to make simple Oldowan tools?

Who did this?

Answer 13

recording brain activity using functional near-infrared spectroscopy as modern human participants learned to make Oldowan and Acheulian stone tools in either a verbal or nonverbal training context.

Putt, 2017

Question 14

What cortical brain areas did Putt (2017) discover were necessary to make Oldowan tools?

Why is this unsurprising?

Answer 14

Unique cortical areas recruited during the Oldowan task include the hand representation portions of the primary sensorimotor cortex in both hemispheres. This suggests the involvement of a lateral premotor system, which is dependent on external visual input to recognize and assign significance to external objects.

This is unsurprising, as the only goal of the Oldowan task is to visually identify ideal platforms and remove flakes until the core is exhausted.

Question 15

Can Oldowan tools be made without verbal teaching?

Answer 15

Yes
but only in the nonverbal group that the left MFG, is activated

recruitment of this network in the nonverbal condition only, suggests that learning to produce simple flakes with-out language requires increased attention to visuo-spatial demands

Question 16

What brain areas are active when the Oldowan tools are being produced using verbal communication

Answer 16

elicits activity in the left dorsal PrG, an area that also is activated when pas-sively reading action words related to the arm

Question 17

Considering the brain areas that are activated when Oldowan are made without verbal communication, what can we infer about the hominins who made them?

Answer 17

Oldowan tool manufacture relies on the coordination of visual attention and motor control to successfully remove simple flakes.

homologous cognitive network is probs active in chimpanzees when they crack nuts with stone tools, or even in capuchin monkeys when they strike two stones together, which can sometimes lead to unintentional flakes similar to those made by early hominins.

results of this experiment point to cognitive abilities that were more ape-like than human-like among hominin toolmakers prior to 1.8 Ma

Question 18

Which brain areas are involved in making Auchelian tools?

What is interesting about the involvement of some of these areas?

Answer 18

Middle and superior temporal cortex (visual, auditory and sensorimotor information), precentral gyrus (visual working memory), and supplementary motor areas: importance of auditory capacities in toolmaking?

Overlap with language circuits: tool making and language shares neural substrates? (Stout et al., 2008)

Question 19

What is the possible role of the auditory brain centre in Auchelian tool making?

What implications could this have had on evolutioin

Answer 19

Acheulian knapping requires the knapper to discriminate between knapping sounds and to assign meaning to those sounds based on how they relate to the hierarchy of goals involved in making a handaxe

Thus, the knapping of Acheulian tools may have played a role in fine-tuning this function in the superior tempo-ral gyrus, perhaps facilitating the evolution of neural connections involved in speech perception

Question 20

What can we infer about the evolution of hominin auditory processing from toolmaking?

Between which taxa was there a noticable shift

Answer 20

the Acheulian techno-complex coincides in timing with the evolution of a derived middle ear anatomy in Homo that was more attuned to human speech frequencies.

Together, fossil and neuroarchaeological evidence now show that a major shift in hominin auditory processing occurred after Homo diverged from Australopithecus and Paranthropus and before the appearance of H. heidelbergensis

Question 21

The adoption of the Acheulian toolkit by early Homo also coin-cides in time with a more unpredictable environment, an increase in brain and body size, and a more diverse diet that relied upon tool-assisted hunting and foraging of large game animals and tough, fibrous plant products. Why is this timing important

Answer 21

As reliable food items became scarcer in this unpredictable environment, individuals who were capable of holding multiple modes of information in mind to guide and coordinate their motor behaviours probably experienced higher RS due to their enhanced ability to produce complex tools.

this allowed these individuals and their offspring greater access to a diverse set of food resources

Question 22

Based off endocasrs, which taxa are more likely to have made the tools at Lomekwi and Gona?

Answer 22

Paranthropus and early Homo - Australopithecus has very primitive frontal lobe

• Homo: Reorganisation may not have happened until erectus
• Paranthropus: One fossil is derived but unclear in other fossils

Question 23

What are the 2 hypotheses of the emergence of human-like hand traits?

Why is it hard to make confident assumptions about hominin hand morphology?

Answer 23

→ before 2-3 Ma: hand use because of bipedalism (at about 6 Ma),
→ at 2-3 Ma: intensive manipulative behaviours tool use and/or nonlithic tool making

Hand fossils are rarely preserved in full - they are often composite and they could be Paranthropus or Homo or a mixture etc

Question 24

How do the 2 different hypotheses for the emergence of modern hands differ in their implied evolutionary scenarios?

Answer 24

→ with bipedalism, no need for long and curved phalanges for climbing trees, so then became shorter (neutral/positive selection) except the thumb,
→ by product of reducing the length of toes for bipedalism (exaptation)

Question 25

What is exaptation

Answer 25

Exaptation (co-option): trait that plays a different role than the one initially played and selected (adaptation) or that was initially nonfunctional (Gould and Vrba, 1982).

Question 26

What are the important aspects of human hand morphology?

Answer 26

robust thumb (muscle attachments),

robust fifth digit with a unique joint to rotate it towards the thumb

Question 27

What are the 3 manipulative abilities in extant humans?

Answer 27

precision handling (rotate and manipulate objects),

forceful precision gripping,

power squeeze gripping of cylindrical objects.

Question 28

Describe the hands of the earliest hominins

Answer 28

Ardipithecus: hand proportions more Old World monkey-like.

Orrorin: thumb human-like (precision grip abilities), more derived than
Australopithecus

Question 29

Describe the manipulative abilities of A. africanus/Prometheus (4)

Answer 29

robust human-like thumb,
curved phalanges,
humanlike trabecular bone pattern,
possibly forceful opposition of the thumb and fingers

Question 30

Describe the manipulative abilities of afarensis (2)

Answer 30

capability of throwing and pounding, possibly precision grip thumb/index

Question 31

Describe the manipulative abilities of sediba

Answer 31

long thumb, pad-to-pad opposition of the thumb and fingers (greater control and manipulation of small objects), clear combination of arboreal locomotion and tool manipulation

Question 32

Which aspect of sediba’s hand morphology is an arboreal trait

Answer 32

long thumb

Question 33

What is the likelihood of afarensis making tools based off hand biomechanics?

Answer 33

musculoskeletal simulation of the fifth digit based on the A. afarensis hand morphology.

Low mobility of the joint, restrict ability to orient the ray towards the handheld object: limited possibility for sufficient grip force to make Lomekwian (large) stone tools

Question 34

What is the biomechanics of Paranthropus’ hand

Answer 34

Derived specific pattern: robusticity pattern on distal phalanges, convergence with quadrupedal monkeys due to similar manual feeding techniques?

If we use mean of measuremetns of distal phalanxes it falls in the range of non human primates

Question 35

Discuss what can be inferred from the fossils about the manual manipulative ability of early Homo hands

Answer 35

OH 86 (Tanzania) dated to 1.84 Ma: proximal phalanx from the fifth ray
different from OH 7 modern human-like proportions. 

• KNM-KP 51260 (Kenya) dated to 1.42 Ma: metacarpal, human-like morphology.
• Contemporaneity with the Acheulian technology (emergence at 1.75 Ma).

Question 36

Describe the biomechanics and thumb of early Homo

Answer 36

Biomechanics: muscle modelling, estimation of the muscle force-generating capacity of the thumb.

• Modern human morphology of the thumb emerged about 2 Ma (thus not in Australopithecus): increased thumb opposition efficiency.

Question 37

What is interesting about the Manipulative abilities in Homo floresiensis?

Why is this important for how we study tool making?

Answer 37

Human-like precision grip (phalanges) but similarities with Australopithecus
(wrist).
Association with Oldowan tool artefacts.

• Is bone morphology a reliable proxy?

(Tocheri et al., 2007; Larson et al., 2009)

Question 38

What do the wrist bones of floresiensis contribute to the debate over the taxon’s validity

Answer 38

Tocheri (2007) found its wrist morphology is closer to that of apes and older hominins compared to Neanderthals and humans (Hopkin, 2007)

This suggests LB1 (floresiensis) is descended from a hominin ancestor that migrated out of Africa before the evolution of the shared, derived wrist morphology that is characteristic of modern humans, Neandertals,and their last common ancestor.

Suggests floresiensis is its own taxon and not a microencephalic H. sapiens (especially as Tocheri (2007) compared wrist to pituitary dwarf and giant, neither of which had similar changes in wrist morphology due to their condition)

Question 39

Is a modern derived human wrist morphology necessary for tool making?

Answer 39

he association of LB1 (H. floresiensis) with direct evidence of stone flaking technology comparable to that found at Oldowan or other Lower Paleolithic sites throughout the Old World provides additional support for the hypothesis that the earliest hominins to use and make stone tools retained primitive hominin wrist morphology

Question 40

What neural connections allow finger dexterity

evidence?

Answer 40

cortico-motoneuronal connections (direct, monosynaptic connections with motoneurons, bypassing the spinal interneurons.)

• projections to motorneurons appear in species that make independent finger movements (in primates) but are not seen in species without.
• Lesions of the corticospinal tract in the medulla leave permanent deficits that are most extreme in finger movement and manipulation.
• n man the direct projections post-natally, appearing at about 9 months. At this age dexterity begins to develop.

Question 41

What are Clark’s (1968) technological modes

Answer 41

Mode 1: flakes - Oldowan

Mode 2: bifacial/ symmetrical tools - Acheulean

Mode 3; levallois (pre-prepared) - Mousterian

Mode 4: Blades - Aurignacian

Mode 5: hafted onto wood - Microlithic

Question 42

When did mode 1, 2, and 3 appear

Answer 42

Mode 1: ~2.6 mya with afarensis and africanus

Mode 2: 1.7mya with habilis and ergaster

Mode 3: 160kya-40kya; associated primarily with the Neanderthals in Europe, and to the earliest anatomically modern humans in North Africa and West Asia.

Question 43

Give the chronology of when different tool modes appeared

Answer 43

Early Stone Age/ Lower Palaeolithic:

Lomeckwian 3.3 Ma (E. Africa)

Mode 1 (Oldowan) 2.58mya E. Africa

Mode 2 (Acheulean) 1.8mya E. Africa

Middle Stone Age/ Middle Palaeolithic:

Mode 3 (Prepared cores, Levallois) 3-400 Ka E or N Africa

Upper Palaeolithic:

Mode 4 (blades, systematically
produced)
50 Ka Levant?

Late Stone Age/ Mesolithic/Post-glacial:

Mode 5 (ephemeral) 80 ka S. Africa

Mode 5 (persistent) 12 Ka Global