Patterns of brachyuran diversity (Decapoda) through time in an archaeological site, “Sambaqui da Tarioba”, Rio das Ostras, southeast Atlantic, Brazil

Abstract

Within the available record of biodiversity from the Holocene are the archaeological sites known as shell mounds (or “sambaquis” in Portuguese). Found in almost all coastal areas around the world, shell mounds show a high abundance of biological remains such as molluscan seashells, bones of fish and mammals, skeletons of sea urchins, and crustacean carapaces (Stein, 1992; Gaspar, 2000; Villagran & Giannini, 2014). However, these archaeological sites are not recognized as good representatives of past biological diversity, because they are artificial accumulations made by prehistoric human populations (Stein, 1992; DeBlasis et al., 2007; Scheel-Ybert et al., 2009; Villagran & Giannin, 2014), representing only a fraction of the total local biodiversity. Despite the fact that shell mounds are artificial dumps or monuments, the biological remains there represent a sample of the existing fauna at the times of their construction (Fursich, 1995; Scheel-Ybert et al., 2006; Lindbladh et al., 2007; Froyd & Willis, 2008; Villagran & Giannin, 2014). Thus, some recent studies have used shell mounds to describe the composition of the fauna of the Holocene, especially that of molluscs and fishes (Souza et al., 2010; Souza et al., 2012; Mendes et al., 2014; Beauclair et al., 2016; Souza et al., 2016).