Bottleneck at Jaramillo for human migration to Iberia and the rest of Europe?

Abstract

In the contemporary paleoanthropological literature, there is a general consensus that the earliest peopling of Europe occurred before the Brunhes–Matuyama geomagnetic polarity reversal at 0.78 Ma, based on convincing magnetostratigraphic evidence from Spain (e.g., Carbonell et al., 1995 and Parés and Perez-Gonzalez, 1999), Italy (Muttoni et al., 2011), and northern Europe (e.g., Parfitt et al., 2005). However, there is intense debate about how much before 0.78 Ma the earliest peopling occurred. Proponents of a long chronology claim that Europe was inhabited well before 1 Ma. There are sites that imply peopling of Europe before the Jaramillo normal geomagnetic polarity subchron (1.07–0.99 Ma; time scale of Lourens et al., 2004), even though the Jaramillo is nowhere to be found in these sections. Proponents of a shorter chronology (Muttoni et al., 2010, Muttoni et al., 2013 and Muttoni et al., 2014) put emphasis on the presence (or absence) of the Jaramillo in key hominin sections, while calling attention to large uncertainties in some of the other dating methods (biostratigraphic, ESR, cosmogenic), to infer that the earliest peopling of Europe occurred in a narrow time window of reverse polarity prior to the Brunhes–Matuyama boundary (0.78 Ma) but after the Jaramillo subchron (0.99–1.07 Ma). The Jaramillo has therefore attained the status of a marker datum useful for separating the long (>1 Ma) from the short (<1 Ma) chronology of the earliest peopling of Europe