Bioarchaeology sampling

Example of utilised molluska remains

At the Ille excavation, there was clear effort to gather bioarchaeological data. This was done on the Molluska remains found on site. There is an aim to understand both ecological and cultural patterns. At the levels below the dated layer of 10,000 years ago, the matrix at the East mouth excavation was totally subjected to flotation and afterwards wet sieved. The heavy fraction that remained after the wet sieving were sun-dried, sorted for biological remains and micro artefacts while at the field base. The light fraction from the flotation were brought back to the ASP laboratory for further sorting and analysis.

Soil Micromorphology

This method was consciously applied throughout the project as a key approach in the objective of understanding the transformations of the landscape in Palawan, and the role humans played in these transformations. It is also an important method for creating finer resolution of evidence for the understanding of the nature of human activity at the Ille site. Samples were taken sometimes using tin casings, which were hammered on features that showed up on the vertical profile, at the West mouth, East Mouth , Outlier, and the Rice Paddy excavations. In most cases however, the samples were carved off the excavation walls in chunks and carefully taken out, packed in layers of bubble-wrap and adhesive tape.

A similar procedure was applied at the Tabon cave site in 2002.

Guano collecting

Consistent with the overall Palawan Island Palaeohistoric project, Dr. Bird collected more samples of guano deposits in caves amongsts the valley's tower karsts. The potential remains high for using guano as proxy evidence for understanding vegetation change in the past. Thick deposits of guano were sampled every 10 cm from top to bottom– taking amounts per sample that were not more than half the content of a 20 cm x 10 cm plastic bag. The samples collected were divided into two sets – one left at the project base camp at Dewil, and the other set was brought to Dr. Bird's laboratory for analysis at St. Andrews University.

As part of the multidiciplinal nature of the research at Dewil, Professor Michael Bird continued on with his study of bird and bat guano deposits, which he started in southern Palawan and around Niah cave in Sarawak. His study intends to fashion a workable approach in utilising the C3 and C4 signatures extracted from guano deposits in a profile. It is expected that these signatures can be identified and used as proxy evidence for the changing nature of the vegetation, and an understanding of the climatic patterns in the area within the time depth of modern human occupation of Island Southeast Asia. he potential remains high for using guano as proxy evidence for understanding vegetation change in the past.

This is significant especially for questions concerning the nature of human-environment interaction in Palawan. For this season, Professor Bird collected samples from columns dug through the guano deposits, some extended to more than two metres. The guano deposits were sampled from the top at intervals of 3 cm. The samples were bagged, and later on were subdivided into two sets – one set was taken back to St. Andrews University for analysis, and the other set was stored on site at the base camp in the Danay family property at New Ibajay. There were also smaller samples of swiflet guano collected from Sinalakan and Tanag caves. These samples will undergo processing for comparative study with the bat guano. The analysis of the guano samples is taking place at the Department of Geography laboratories of St. Andrews University in Scotland.