An assessment of the Arabic RH5 Neolithic fishing community’s mortuary practices by examining human rib cross-sections for bioerosion patterns

•Diagenesis has been observed among rib elements.•Some of the ribs were burnt others were not.•Differential bioerosion appears to be related to the duration of open-air decomposition prior to burial.•A method has been developed to estimate time of open-air decomposition The purpose of this research is to offer a micro-anatomical skeletal means for understanding the funeral practices of the Neolithic fishing community of Ra’s al Hamra 5, which is located on the Arabian Peninsula. The archaeological site is located on the Oman gulf of the Arabian Sea coast near the suburb of Qurum; located near the Omani capital Muscat. Archaeological evidence dates the graveyard between 3800 BCE. and 3300 BCE. The burials focused on in this research come from Area 43, a part of the site that held partially burnt and commingled human remains. The study was conducted on 24 histological samples taken from ribs. The traces of bioerosion found on the non-burnt and burnt samples are analyzed. The percentage of bioerosion for each samplehas been documented (area of involvement; Ct.BAD/Ct.Ar.). Less than 5% of the rib cross-sections lack diagenetic alteration. Of the remaining samples, 52.2% show less than 49% diagenetic alteration of the cortical cross-sectional area, while 47.8% of the samples show greater than 50% or more of diagenetic change to the bone matrix. The variability in bioerosion indicates that different lengths of surface decomposition time were involved during funeral practices.This suggests that there may have been a degree of cultural variation employed as these Neolithic people buried their dead. Our results suggest that some of the remains were buried shortly after death. Other remains were exposed to open-air decomposition prior to both burning and burial.