The need for disposable (sold or killed) workforce existed even among hunter-gatherers.
Read "Slaves, chiefs and labour on the northern Northwest Coast", Kenneth M. Ames, in World Archaeology Vol. 33(1): 1-17 The Archaeology of Slavery
Prehistory was probably far from this egalitarian world that we sometimes dream about : not only because of the individual or inherited differences in fitness, strength, intelligence, smartness ... but also because of transmissible inequalities in social status.
Most probably, as nowadays, every tedious work ( but also specialist's work : see page 2 ), would have been a slave's one ( and a commoner's one ). Hence each of my primitive technology experiment is also reminiscent of primitive slavery (and of low status activities of all times).
Are my slave ancestors talking through my acts ? :-)
Maybe not... As long as I practice very primitive technology, I follow the voice of those ancestors who lived before slavery appeared ... because slavery would appear with higher demands of labour, and that may be incompatible with very primitive technologies [ ex. see the comparison between fishing with a spear and fishing with a gill net on page 12]
on page 2
The evolution of complexity, especially of social inequality, has been a central research question in hunter-gatherer archaeology during the past twenty years. including on the Northwest Coast (see Ames (1994) for a review and citations, also Matson and Coupland(1995) and Ames and Maschner (1999». It is now clear that some form of permanent social ranking or stratification was present on the coast 3000 calendar years ago, if not earlier.on page 4
The crucial point here is that slaves were the only labour that Northwest Coast chiefs could reliably control (Ames 1995). [...]
Disposal of slaves through trade or killing could remove excess consumers. People with crucial skills could be acquired. Maquinna let Jewitt live because Jewitt was a blacksmith.
on page 5
Women and girls were preferred as slaves.on page 11
There may have been two or three major increases in labour demands after 1850 BC. [...]
It is not until after 1850 BC that there is strong evidence for intensive exploitation of a range of
resources, including salmon. It is around this time that there is evidence for increased
production, in both harvesting and processing, that would suggest higher labour demands. [...]
The woodworking tools and other evidence presented here clearly indicate an expanded industrial role of woodworking and carpentry. [...]
There is evidence for specialization in this period, including working in copper and possibly woodworking. There is no evidence for technological innovations that would significantly enhance labour efficiency.on page 11-12
It is difficult to quantify labour demands associated with these changes. However, we can indicate the labour costs associated with increased use of weirs, baskets and nets (mass capture techniques). Lindstrom (1996) develops useful data on the costs of various fishing techniques. To keep this brief, I shall compare the two extremes of fishing technology: spears and gill nets. She estimates a fish spear takes four hours to make. Under optimum conditions, a person can harvest ten fish per hour with a spear. In contrast, a gill net, depending on the gauge, takes between 205 and 2,220 hours to make, although nets may capture fish at a rate of a fish every two and a half minutes in optimum conditions. Additionally, a spear, once made, may require little maintenance, while a net requires continual maintenance. Other bulk harvesting techniques (weirs, basket traps) need less time to make, but are still costly, relative to a spear or hook and line. Expanded use of bulk harvesting techniques, then, imposed sharply increased labour costs at both ends of the productive chain, in making the equipment and in processing the increased catch.on page 12
Increased labour demands also occurred after AD 500 (the Late Pacific). A range of new heavy-duty tools appears in the artefact assemblages including piledrivers and two varieties of large adze blades. The densities of adze blades of all sizes double and those of mauls and percussion crease fivefold, indicating a significant increase in heavy woodworking. It is probably no coincidence that very large wooden houses appear in the record for the first time on the northern coast.on page 14
During the Early Modern period, northern Northwest Coast social organization was matrilineal, and it is possible that the shift in labret wear to only females (the historic pattern) marks the emergence of matrilineality (Cybulski 1993). Raiding and warfare tactics also change, leading to increased construction of fortifications (which require labour). Maschner (1992) argues this change was caused by the adoption of the bow and arrow as a weapon. In sum, this appears to be a period of considerable flux and violence.These circumstances combine to suggest that this is a very plausible time for slavery to develop. [...]
If slavery did not develop on the coast until the Late Pacific, then the permanent elite of the Middle Pacific may have evolved in the absence of control over non-kin labour. The relationship of that elite and the artisans who produced the copper, shell and amber objects is currently unknown, although certain portions of the elite appear to have controlled use and disposition of the objects themselves. If they did not control labour, what did they control, aside from some prestige goods? This question becomes even more pressing in light of the evidence for ranking of extended kin groups and of villages in Prince Rupert Harbour during the Middle Pacific. As interesting as this question is, there are presently no data with which to address it.