Climatic change and diet of the pre-Hispanic population of Gran Canaria (Canary Archipelago, Spain) during the Medieval Warm Period and Little Ice Age

摘要

The hard and soft tissue remains of a pre-Hispanic population of the Gran Canaria Island at six different archaeological localities were studied using C-14 dating and stable isotope compositions. Radiocarbon dating indicates island occupation ranging from the beginning of the 7th to the mid-14th century. We analyzed the oxygen isotope compositions of apatite phosphate bones of some pre-Hispanic individuals. The oxygen isotope compositions of meteoric water (delta O-18(w)) show a significant decrease from -2.1 +/- 1.5 to-4.4 +/- 1.2 parts per thousand (VSMOW) from the Medieval Warm Period (MWP) to the Little Ice Age (LIA). This is interpreted to reflect a decrease in air temperature by about 5 +/- 3 degrees C. Archaeological data along with delta C-13, delta N-15 and delta S-34 values of soft tissue indicate that the pre-Hispanic population from Gran Canaria relied on agriculture throughout the 7th to mid-14th century. However, a significant contribution of seafood to the diet of the pre-Hispanic population is observed at archaeological sites located close to the shore. These results suggest cultural resilience in the pre-Hispanic population of Gran Canaria, reflected in the relative constancy of their diet in light of climate change.