Clarifying the context, dating and age range of the Gondolin hominins and Paranthropus in South Africa

In a recent article, Grine et al. (2012) provided a thorough analysis of the GD A-2 Paranthropus robustus M2, one of the two hominin specimens recovered from the Gondolin palaeocave in the northeastern corner of the UNESCO Cradle of Humankind World Heritage Site (`Cradle?), South Africa (Menter et al., 1999). Although we appreciate the detailed approach of their research on the hominin specimen, we wish to clarify several incorrect citations of our work at the Gondolin site, including the probable origin of the hominin specimens and age of the deposits. Moreover, Grine et al. (2012) suggest that Paranthropus occurs in South Africa between 1.9 and 1.5 million years ago (Ma), an age range that does not reflect the ages produced by a number of dating studies on Paranthropus-bearing sites and continues to argue for the reliability of biochronology based on correlations with East Africa over existing chronometric ages that exist for the sites. With recent advances in a number of dating methods that are applicable to the South African caves and studies that show their accurate cross correlation ( Lacruz et al., 2002, Herries et al., 2010 and Herries et al., 2013), it is no longer necessary to rely on faunal estimations for the age of these deposits based on correlations with the other end of the African continent, and with little data existing in between. Moreover, recent geochronological studies on the South African caves have shown that many dates based on biochronological analysis with sites in East Africa are up to half a million years too old ( Herries et al., 2010 and Herries and Shaw, 2011). This discordance may relate to South Africa functioning as both a continuous population refuge and geographic origin for several Pleistocene and extant lineages (see summary in Lorenzen et al., 2012; also Pickford, 2004). This expanding dataset on the complex, dynamic biogeography of African mammals precludes the assumption that the South and East African sites, separated by 3000?4000 km, had homologous first/last appearance dates of species/lineages. It also highlights the importance of using the current chronometric dating framework of South African localities to establish revised, `local? biochronological data, particularly given the recycling in the literature of early biochronological dates that, themselves, were based in part on South African site dates that have been revised in recent years. Here we review the dated record of Paranthropus in South Africa (2.0?