Evolution and humans: stone artifacts interpreted (Evolution)

by David Turell , Tuesday, November 07, 2017, 17:16 (2571 days ago) @ David Turell

It is not known if early hominin stone tools were culturally transmitted or not:

http://www.journals.uchicago.edu/doi/10.1086/693846

Abstract:

"We have learned much about tool use in nonhumans since the discovery of Oldowan stone tools. ... We pragmatically suggest resetting the null hypothesis for the processes underlying early stone tool production. The null hypothesis that we prefer is that early stone tools might have been so-called latent solutions rather than cultural material that derived from—and depended upon—modern human-like high-fidelity cultural transmission. This simple shift in perspective prioritizes the systematic investigation of more parsimonious potential explanations and forces us to demonstrate, rather than presume, that stone tools could not have existed without high-fidelity cultural transmission.

"The archaeological record clearly shows that, by at least 2.6 million years ago, one or more fossil hominin taxa were frequently making and using stone tools. A defining (and puzzling) feature of early stone tool assemblages is that patterns of production appear to have few identifiable or directional changes over hundreds of thousands of years.....In short, researchers interested in what the archaeological record can tell us about cognition commonly ascribe modern human cognitive skills, such as shared intentionality, conformity, overimitation, and teaching (skills that many have argued are key to the sophisticated way that modern humans, but not other living primates, transmit information socially), to Pliocene and Early Pleistocene hominins.

"It is not surprising that archaeologists see signs of modern human cognition in early stone tools given that the technology appears at once so impressive and so foreign. If hive making were culturally transmitted among bees (it is not), then one could excuse a hapless “modern bee-man” visitor to a museum of “prehistoric bee artifacts” for making a similar inference about the cognitive abilities of her Early Pleistocene ancestors from the impressively ordered and complex nature of her lineage’s presumed “culture material”. Despite the complexity of beehives, there is no evidence that the structure of these forms reflects anything more sophisticated than low-fidelity social learning.

***

"For us, however, a null hypothesis that this technology was passed from hominin brain to brain and from generation to generation via cultural transmission in a way reminiscent of, if not exactly like, that used by humans today is not clearly supported by the archaeological evidence. Here, we suggest resetting the null hypothesis for early stone tool production, ... before we reach a hypothesis that invokes modern high-fidelity social learning mechanisms (i.e., cultural transmission) in hominin species living more than a million years ago. The null hypothesis that we prefer is that early stone tools might have been so-called latent solutions rather than cultural material.

"Our concern is that current explanations that view even the earliest stone tools as necessarily cultural products likely overinterpret the underlying cognitive mechanisms. This view on the archaeological record comes in part from research on tool use by living great apes (i.e., the phylogenetically most appropriate comparison group), which faces similar difficulties. For instance, in light of available evidence, one can make the argument that high-fidelity cultural transmission is not necessarily responsible for many great ape tool “cultures”. Instead, population-wide behaviors currently described as cultural are largely the result of individual learning, loosely connected by low-fidelity social learning, such as stimulus enhancement.

***

"we propose that—at this time—a more appropriate null hypothesis is that the first stone tools were latent solutions resulting from individual learning augmented by low-fidelity social learning. The question that must then be asked is what data from Oldowan, Acheulean, or even Middle Stone Age/Middle Paleolithic stone tool assemblages falsify this hypothesis? In other words, when we set aside the presumption that the very presence of similar stone tools must mean cumulative culture, we can ask the question of fundamental interest to human origins—when did cumulative culture begin?

***

"The time seems right to reset the null hypothesis for early stone tools and cultural transmission. The picture emerging from both primate studies and Paleolithic archaeology is one in which simple stone tool technology might not require the cultural scaffolding or related cognitive hardware that modern human flintknappers employ.

***

"One might point to increased brain size as the obvious explanation for such a change in hominin technology, but the toolmaking abilities of the relatively small-brained Homo floresiensis (or the beehives of tiny-brained bees) show that the relationship between brain size and technological sophistication, including examples of cumulative culture in the case of hominins, is not as simple or direct as it was once widely thought to be.

***

" We count ourselves among those. 2016) who think the best practice, in this case, is to assume that early stone tools were not culturally transmitted until it is demonstrated otherwise."

Comment: It is interesting that these archeologists are not sure that brain size is an issue. Cultural transmission is a major issue.