Paleoecology of Western Canada: vegetation dynamics and paleoclimate during the Quaternary and Eocene.

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My research program aims to reconstruct patterns of change in vegetation and ecosystem structure in Western Canada, and to use this information to assess how environmental factors, in particular, climate, are responsible for those changes. Within this framework, we are focusing on several research topics. The first area of study is the glacial and biological history of Haida Gwaii (the Queen Charlotte Islands), also known as the "Canadian Galapagos." The origin of the unique fauna and flora of the Haida Gwaii is controversial, and centres on glacial history and the likely existence of glacial refuges during the last and previous glaciation. Prior to the last glacial maximum (~20,000 years ago), there was an earlier, larger glaciation that is too old to study by radiocarbon dating methods. We will use new dating techniques and employ pollen and plant fossils on Graham Island to reconstruct plant communities and climatic conditions, and to understand the effects of climate change and disturbance on plant survival and local extinction. We will also examine pollen fossils from the sediment core of a late-glacial pond adjacent to the Kilgii Gwaay archaeological site in the South Moresby area of Haida Gwaii. Using the results, we will reconstruct the environment at this particular site, which is one of the oldest (9,500 years) human occupation sites in Haida Gwaii. Pollen analysis will also test whether a sudden cooling event (Younger Dryas) occurred here, and we will use the information to understand how very rapid global climate change affected plant, animal, and human communities. Finally, we will study the connections between rapid climatic warming and biodiversity 53-50 million years ago by using well-preserved fossil insects and plants from that period (the Early Eocene) in the Okanagan highlands of south-central BC. This period had the warmest climate since extinction of dinosaurs, and marks the beginning of ecosystems that resemble modern forests in North America, Asia, and Europe. These fossils can tell us how biodiversity changed in a past rapidly warming (and possibly future?) global climate.