Marine sponges become entrained into glacial ice at the glacial-marine sediment interface and eventually become exposed on the upper surface of the glacier through processes of ablation. The transit time from glacial base to glacial surface is estimated to be in the order of 500-5000 years. Exposed 'fossil' sponge material at Bratina Island, McMurdo Ice Shelf, was collected and dating was attempted although extremely difficult. The samples could include signals from microbial endosymbionts and may be used for comparative analyses with homologous extant organisms. Microbial molecular evolution evidence was planned to be investigated and species diversity was analysed.