Differential representation of human skeletal remains in eroded and redeposited coastal deposits: A case study from the Marshall Islands

A historical cemetery on Majuro Atoll, Republic of the Marshall Islands, was partially washed away during an exceptional seasonal high tide. The osteological analysis of the human remains washed out by the tides showed that the anatomical representation of the bones found on the shoreline is distinctly skewed, caused by the erosion of the graves by wave action and the differential transport of bones by waves and currents. The two major factors involved in the observed differential preservation of skeletal elements appear to be (i) the overall weight of the bone and (ii) its ability to float. Light-weighted bones, such as the phalanges, or heavily spongiotic bones, such as vertebrae and patellae, float easily and — by wave and tidal action — can be carried out to sea, leaving the heavier bones, such as femora, tibiae, or non-floating bones, such as the crania and mandibles, behind.