South Arabia’s prehistoric monument landscape shows social resilience to climate change

PLOS One | https://doi.org/10.1371/journal.pone.0323544 May 28, 2025 15 / 24 Social resilience emerges from coping, adaptive, and transformative capacities to “tolerate, absorb or adjust to environ- mental and social threats” [97, p.8]. These are capacities all linked at the community level through network densities that “generate and produce assets that advance shared objectives” [98, p.3]. We consider monuments as assets that facili- tated social belonging and were technically adjustable to sustain social cohesion for desert pastoralists who did not aban- don herding with environmental changes. Such changes included reduced graze, drying springs, changes in frequency and distributions of seeps, and in some eras, amelioration of rangeland. In contrast to people occupying the vegetated plateau and escarpment, populations in the arid zone relied on monu- ment construction and subsequent visits for social contacts that defined their socioeconomic and cultural networks. We attribute monuments’ distribution to their roles in communicating socio-cultural messages to people often absent. Mon- uments communicate a culturally specific, shared meaning from builders to contemporaries and facilitate exchange and social relationships [99]. Builders may also have intended to signal subsequent generations or to reify builders’ attach- ments to landscapes and places already established by prior generations. The placement of monuments could communicate environmental information like grazing or routes or could be reactive

to and built alongside an established route. Monument placement close to water and streambeds, where vegetation is highest, reflects that these are the places desert people frequent. These low-lying areas offer graze and browse, shade under trees, rockshelters, and travel routes of least effort. With consistently higher biomass in the escarpment through time, populations there were probably denser than in the arid interior. Dhofar’s mountain people could rely on direct contact to build social networks for resilient communities, rather Fig 7. Boxplots comparing total stone volumes across several monument groupings. Groupings include the five monument types, the two cate- gories of technological requirement, and whether or not one or more large stones (>0.75 m) were present. We also compare the latter for all monuments, within monument types, and the two categories of technological requirement. The letters show the results of Tukey HSD post hoc pairwise comparisons following ANOVA tests. Monument types with letters in common indicate no statistically significant differences, while different letters indicate statistically significant differences. https://doi.org/10.1371/journal.pone.0323544.g007