The impact of the environment and sediments on the state of preservation of fossil bones

Studies on fossil bone microbial communities are scarce, and even fewer studies were performed in cave deposits. Muierilor and Ur?ilor of Chi?cau caves are some of Romania's most important paleontological and archaeological deposits. For our research, sediments and fossil bones were sampled, and whole community 16S rRNA gene-based metabarcoding analyses were performed. The identified microbiome indicated the presence of bacteria in fossil bone samples and bacteria previously identified in bone-impacted sediments in cave sediments. Both findings point to an equilibrium microbiome, common for both air-exposed fossil bones and substrates. These findings are important to understand fossil bones' deposition and preservation in different cave conditions and assess the taphonomical context for further excavations and/or sampling to select the best samples for various paleontological analyses.