surface current flowing eastwards. This represents a significant barrier to human migration
without sturdy watercraft, though a few modern athletes have swum it in as little as six
hours. The most bullish bid for a possible crossing by an earlier hominin species (Arribas
and Palmqvist, 1999) claims a sea-level fall of 200 m during the Aullan event (1.8–1.6 Mya)
would result in the narrowing of this passage up to 6.5 km approximately, but even with a
greater sea level fall there is a significant cross current as barrier.