A basis of bone

In a target article in Behavioral and Brain Sciences, Wendy Wilkins and Jenny Wakefield (1995a, 1995b, 1996) present ‘a scenario for the emergence of the neural preconditions for language in the hominid lineage’. This scenario has at its core a conclusion to which I will refer as ‘the Homo habilis conclusion’. Stated first in Section 1.2, it reads as follows:

The Homo habilis conclusion

Homo habilis was the first hominid to meet the neural preconditions for language (Wilkins and Wakefield 1995a: 161; see also Composite Inference 1 in Section 1.2).

Wilkins and Wakefield (1996: 795) arrive at this conclusion by constructing a chain of inferences which they describe in outline as follows: ‘[We] infer cognitive capacity from admittedly scant information about neuroanatomical structure that can be gleaned from the available (and often) imperfect endocasts.’ This statement of Wilkins and Wakefield's captures the essence of a window on the evolution of language that has been used in various fields that study human evolution. These include palaeoneurology (Zollikofer and Ponce de Leόn 2013: 24) and the multidisciplinary area referred to as ‘evolutionary linguistics’. In view of the starting point of this chain of inferences, I refer to this window as the ‘fossil-skull window’. Typologically, this window resembles the shell-bead window in two general ways. That is, the fossil-skull window is a correlate window from the viewpoint of the logical nature of the inferential steps; and it is a composite window from the viewpoint of structure.

There are several variants of the fossil-skull window. In this chapter I examine what may be referred to as the ‘classic variant’ of the fossil-skull window – the variant that provides for the chain of inferential steps set out in Section 1.2. My aim is first and foremost to further clarify the conceptual foundations of the Windows Approach. And, second, to assess the heuristic potential of this variant of the window. To this end, I will pay special attention to two of the issues that have been vigorously debated by Wilkins and Wakefield and their critics in BBS (vol. 18, 1995, and vol. 19, 1996) and elsewhere (Wilkins 2005, 2007, 2009, 2012).