“Historical ecology and the record of human impact in the Galapagos Islands”
- To use pollen, micro-charcoal, sedimentation rates, peat humification and other environmental proxies to reconstruct environmental change in the Galapagos over the past ~3000 years.
- To use advanced chronometric techniques such as 210Pb and fine-resolution 14C analysis to provide a reliable chronology for archaeological and palaeoenvironmental records.
- To confirm the age of first human occupation of the islands, and investigate the relationship pre-European visitors had with the Galapagos environment. This information will contribute to the understanding of Pacific prehistoric migration.
The Galapagos Islands are famed for their historical significance, as well as their ecological importance. Scientists, tourists and residents have been attracted to the Islands since Darwin’s 1835 visit. There is now a permanent population of over 15000, with associated environmental degradation, which is of great concern to conservationists. Among the conservation threats the archipelago faces are introduced flora and fauna, illegal fishing and large scale exploitation of other marine resources, unplanned urban growth, habitat fragmentation and land clearing, waste disposal and harbour pollution.
This research will investigate the ecological impact of humans on the islands over time, by quantifying introduced plant species, burning practices, land degradation (analysis of changes to sedimentation rates), and possibly the impact of climate change on vegetation communities. An important aspect of the work will be providing a high resolution, accurate chronology for both the palaeoecological information gathered, and archaeological work to be undertaken by other researchers during the course of the project. ANSTO 14C AMS and Po/Ra dating facilities be used to establish this chronology.
The project as a whole is looking at human colonisation and environmental change on the Galapagos, with the aim of answering important questions about the nature of prehistoric human migration across the Pacific, interaction between Polynesian and American Indian groups, and the impact these early visitors may have had on the islands.
By combining evidence from palaeoecological and archaeological research, a substantial dataset will be created. This will be strong new evidence used by the team of investigators to help test the theories about Pacific colonization, including the effect of El Nino Southern Oscillation (ENSO) on Pacific migration. The location of the Galapagos Islands (equatorial, east Pacific) means that they are strongly affected by the ENSO phenomenon and are therefore ideally placed to provide a long term ENSO record. Comparisons with other Pacific archaeological and palaeoecological records can be made.
Previous archaeological investigations on the islands have discovered artefacts that stratigraphically underlie European archaeology, apparently from recognisable American Indian cultures. The archaeology team involved in the current research plans to re-survey and excavate sites in the localities of previously reported sites, and use modern geochemical and thermoluminescence analysis (both to be carried out at ANU) to establish the source and age of the artefacts.