May 31, 2024

Public workspaceHafting tests on tanged blanks

Hafting tests on tanged blanks
  • Nassim Zejly1,
  • Bonnie Wright1,
  • Fanny Olivier1,
  • Narciso Domingos Sabao1
  • 1MNHN
Open access
Protocol CitationNassim Zejly, Bonnie Wright, Fanny Olivier, Narciso Domingos Sabao 2024. Hafting tests on tanged blanks. protocols.io https://dx.doi.org/10.17504/protocols.io.x54v92jmml3e/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License,  which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We used this protocol and it's working
Created: April 20, 2024
Last Modified: May 31, 2024
Protocol Integer ID: 98546
Keywords: archeology, experimentation, archeozoology, lithic, knapping, hafting, balistics, use-wear, MSA
Abstract
By the end of the Middle Pleistocene and the beginning of the Late Pleistocene (around 150,000 - 130,000 years ago), the Middle Stone Age in North Africa witnessed the emergence of tang technology. This innovation is characterized as a technical solution that facilitates hafting. Moreover, this technical behavior was consistently represented as point technology. This notion leads to the assumption that the tang was used for hafting in an axial orientation, with the tang being inserted into another material like wood or bone. However, what about the rest of the artifacts? What if the tang was not inserted but used for fixation instead?

In our experimental work, we explored alternative hafting methods where the tang was not inserted but used for fixation. These methods involved testing two hafting systems: the juxtaposition of the tanged artifacts onto wooden sticks, and the insertion of one edge adjacent to the tang. The choice of hafting systems was motivated by the thickness distribution of the produced convergent artifacts.

After hafting, we tested the functionality of these artifacts through three main activities: throwing the spear points, using the spears for penetration, and conducting butchering activities. The first two activities were tested on a simulation of animal carcasses using a mixture of gelatin and pig bones (two scapulae and two radius ulnae), while the butchering activities were conducted on fresh pig limbs.
Materials
- lithic raw material (ideally flint)
- wooden sticks
- knife
- animal resin
- gelatine
- vegetal fibre
- water
- hotplate
- cooking pot
- gloves
- animal bones (scapulae, radius ulnae)
- mould of big dimensions (46*31 cm)
- dinolite
1) Animal resin preparation : here is the followed recipe
1) Animal resin preparation : here is the followed recipe
Purify the water by boiling it, then let it cool down.
Put twice as much water than resin, then let it sit for 24 hours.
Mix
Overnight
The next morning, heat the mixture using a bain marie, without going over 60°.
IMG_5102.png
Animal resin and water heated at 60°


Temperature
2) Gelatine tests : 4 different test were made to find out which is best for the fake carcass
2) Gelatine tests : 4 different test were made to find out which is best for the fake carcass
1st test
450ml of water for 50g of gelatine : success.
IMG_5053.png
Two gelatine tests

IMG_5079.png
Packs of gelatine used in the experimentation

2nd test :
350ml of water for 50g of gelatine : success.
IMG_5081.png
Flake stuck inside the finished gelatine

3rd test :
400ml of water for 50g of gelatine : success.
4rth test :
450ml of distilled water for 50g of gelatine : success.
3) Gelatine preparation
3) Gelatine preparation
We opted for 5L of water for 730g of gelatine.
Mix
Bones disposal inside of the future block of gelatine.
IMG_3343.png
The bones are disposed in the mould

We wedged the sitting gelatine so that it covered the scapulae.
image3019.png
The wedge is circled in red


Let it sit for 24 hours, the temperature must stay rather cool, then remove from the mould.
IMG_3518.png
Remove the gelatine from the mould 1/2

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Remove the gelatine from the mould 2/2

Overnight
4) Knapping
4) Knapping

IMG_5030.png
Production of the blanks

IMG_3438.png
Example of predetermined blank

IMG_3432.png
Limestone hammers used for the creation of the tang by bifacial removals

Production of (convergent) blanks : 11 in total.
IMG_20240422_121233.png
Each of them were assigned to a specific use (2 were eliminated from this picture)







Pictures and basic structural drawings of the blanks.
IMG_20240422_110603.jpg
Every blank is registered and described in the database


5) Hafting
5) Hafting
Lateral hafting (8)
Material required :
- tanged blank
- standardised wooden stick
- animal resin
- vegetal fibre
Saw the wooden stick in order to split it widely enough to insert the tanged blank as desired.
IMG_20240422_115933.png
The wooden stick is sawed

Insert the tanged blank in the splitted stick by pressing the tang towards the bottom end of the stick and inserting one of the lateral parts of the blank inside the wood.
IMG_3445.png
Tanged blank inserted in the wood laterally

Maintain the position and cover the whole with animal resin (on top and inside of the wood + around the tool). Covering it by spinning above the pot full of animal resin might be easier.
Fix the point by using the vegetal fibre. Secure it by covering as much as you can, but let the active part of the spear show.

photo fixation.jpg
The spear is secured by vegetal fibre

Add an extra layer of animal resin on top of the vegetal fibre.
IMG_3453.png
Another layer of animal resin is added

Let the spear dry.
IMG_3525.png
Spear hafted laterally

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The spears are drying

Axial Axhafting (6)
Material required :
- tanged blank
- standardised wooden stick
- animal resin
- vegetal fibre
Saw the wooden stick in order to split it widely enough to insert the tanged blank as desired.
Reduce the thickness of the stick on the end part and put the tang of the blank on top of the stick. If you use this method, your hafting device must be solid.
Maintain the position and cover the whole with animal resin (on top and inside of the wood + around the tool). Covering it by spinning above the pot full of animal resin might be easier.
Fix the point by using the vegetal fibre. Secure it by covering as much as you can, but let the active part of the spear show.
Let the spear dry.
IMG_3566.png
Spear hafted axially (profile view)

IMG_3562.png
Spear hafted axially (crossed fixation)

Additional step for the hafting of knives.
Saw your wooden stick to the desired length before hafting the knife.
IMG_20240422_141453.jpg
Drying knife (shorter stick)

6) Spear use
6) Spear use
1d
Take a picture of everything (for the before / after use comparison).
Cutting : only one active part used on one raw material (pig limbs).

The cutting was done on pig’s trotters. There were two users, doing a skinning action.
We cut 7 times all around the leg and every 2 cm, then removed the strips of skin by cutting into the fat. We decided to carry out this action to observe at which level of the paw the marks on the bone are most visible.

Participant 1, who instead moved the knife back and forth, achieved a time of 28.15 minutes for the 7 rounds and 28.28 minutes for removing the strips of skin. Which makes a complete time of 56.43 minutes.

Participant 2, who cut with a rather sharp gesture, achieved a time of 19 minutes for the 7 rounds and 21.38 minutes to remove the strips of skin. Which makes a total time of 40.38 minutes.
Piercing : static activity : no run-up. The target is at the experimentator's feet.
Don't hesitate to register individual information (height, weight, hands dimensions...)
Every use was filmed and a picture of the spear was captured after every use.
Every impact was located on the gelatine and marked, especially of a bone was touched.
IMG_3732.png
Picture of the impact on the gelatine after every use


Capture d'écran 2024-05-28 105631.png
The user was knealing while piercing the target

Throwing : Settle with a fix distance for all of the users.
Don't hesitate to register individual information (height, weight, hands dimensions...)
Every use was filmed and a picture of the spear was captured after every use.
Every impact was located on the gelatine and marked, especially of a bone was touched.
image832.png
The macro-trace of the impact on the tool is circled in red

IMG_3662.png
Fix the same distance for every user for the throwing

IMG_3810.png
Impact on a bone inside of the gelatine

7) Unhafting
7) Unhafting
Cut the vegetal fibre with a knife and carefully extract every blank.
IMG_20240423_153038.jpg
Unhafting

Label every blank.
IMG_20240423_160243.jpg
Every blank is labelled

Extract the potential splinters stuck in the gelatine.
8) Washing
8) Washing
Lithics : 30 minutes in hot water, then dry with a paper towl.
IMG_20240423_163506.jpg
The tools are washed in hot water to remove the animal resin

Bones : extract from gelatine, then put in boiling water.
IMG_20240423_163307.jpg
The bones are boiled

IMG_20240423_174622.jpg
The impact traces are located on the extracted bones

IMG_20240423_152045.jpg
The bones and splinters are extracted from the gelatine

9) Analysis
9) Analysis
Bone analysis.
Take scaled pictures of the boiled bones.

WhatsApp Image 2024-05-28 at 18.28.58.jpeg
Scapula A after boiling process

Identify the traces on the bones and to which use they correspond to.
g2012.png
Scapula A with circled traces

Lithics analysis.
Check the documentation for every use and register how many takes the participants succeeded in, for each use, each hafting system.
image.png
Proportion of success by participant across rounds

image.png
Proportion of success for every tool orientation per participant ; "Hori" for axial fixation and "Verti" for the lateral insertion and fixation

image.png
Box plot representing the success ratio of Participant 1 ( Domingos) and participant 2 (Fanny )
Employ statistical tests by using the R package, to assess whether there were significant differences in success rates between orientations ("Hori" and "Verti"). Two common statistical tests, namely the two-sample t-test and the Wilcoxon rank-sum test, were used to compare success proportions for each participant individually and when their data were combined.

Capture d’écran 2024-05-29 à 2.06.21 PM.png
T-test for partIcipant 1


Capture d’écran 2024-05-29 à 2.05.48 PM.png
T-test for partIcipant 2


Capture d’écran 2024-05-29 à 2.05.24 PM.png
T-test for both partIcipant

Capture d’écran 2024-05-29 à 2.04.18 PM.png
Wilcoxon test for participant 1

Capture d’écran 2024-05-29 à 2.03.46 PM.png
Wilcoxon test for participant 2

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Wilcoxon test for both participant


Use a dinolite to observe the traces of impact on the different types of hafting / activities.
Describe the traces and locate them on every blank.
F2_dino.png
Impacts on a blank from a lateral hafting device

raccord D1 dino.png
Impacts on a blank from an axial hafting device (with a matching splinter)



Protocol references
1. McBrearty S. & Brooks .A. (2000) - The revolution that wasn’t a new interpretation of the origin of modern human behavior, Journal of human evolution 39, 5, p.453–563.
2. Clark, J. D. (1970) - The prehistory of Africa.
3. Clark, J.D. (1989) - The origin and spread of modern humans: a broad perspective on the African evidence. In: Mellars, P.A., Stringer, C. (Eds.)
4. Scerri, E. M. (2013) - On the spatial and technological organisation of hafting modifications in the North African Middle Stone Age. Journal of archaeological science, 40(12), 4234-4248.
5. Tomasso, S., & Rots, V. (2018) - What is the use of shaping a tang? Tool use and hafting of tanged tools in the Aterian of Northern Africa. Archaeological and Anthropological Sciences, 10, 1389-1417.
6. Borel A., Chacón M.G., Pleurdeau D., Mester Z. (2019) - Archéologie expérimentale : théorie et pratique. Manuel d’accompagnement., Agence Universitaire de la Francophonie et LabEx BCDiv.