The earliest colonisation of oceanic islands by Homo sapiens occurred ~50 000–30 000 years ago in the Western Pacific, yet how this was achieved remains a matter of debate. With a focus on East Asia, the research presented here tests the hypothesis that bamboo rafts were used for these early maritime migrations. The authors review the evidence for Palaeolithic seafaring in East Asia as the context for an experimental archaeology project to build two bamboo watercraft. Sea trials demonstrate the unsuitability of bamboo, at least in East Asia, indicating that more sophisticated and durable vessels would have been required to traverse the Kuroshio Current.

Molecular dynamics simulations of compression deformation of $\left[ {11\bar 20} \right]$-textured 2-dimensional polycrystalline pure Mg, Mg–0.1 at.%Al, and Mg–1.0 at.%Al models were performed at 5 and 300 K. A $\left\{ {10\bar 11} \right\}$ twin nucleated before formation of a $\left\{ {10\bar 12} \right\}$ twin in the simulations at 5 K, while a $\left\{ {10\bar 11} \right\}$ twin nucleated after formation of a $\left\{ {10\bar 12} \right\}$ twin in the simulations at 300 K. The formation of a $\left\{ {10\bar 11} \right\}$ twin was the result of the glide of pyramidal 〈c + a〉 partial dislocations of ${1 \mathord{\left/ {\vphantom {1 6}} \right. \kern-\nulldelimiterspace} 6}\left\{ {10\bar 11} \right\}\left[ {\bar 2023} \right]$. $\left\{ {10\bar 11} \right\}$ twin formation was suppressed at the sites around the Al atoms because the strong Mg–Al bond suppresses atomic shuffling. However, formation was not suppressed at the sites away from the Al atoms because the effect of strong Mg–Al bond is short range. On the other hand, because $\left\{ {10\bar 12} \right\}$ twinning requires the simultaneous glide of zonal dislocations, Al inevitably suppressed $\left\{ {10\bar 12} \right\}$ twinning.