ASYMMETRICAL RESPONSES OF WOODRATS (NEOTOMA SP.) TO LATE QUATERNARY CLIMATE

Determining how species will respond to anthropogenic climate change is one driver of modern scientific inquiries. However, species have responded to climatic change in the past. A historical perspective can illuminate species responses to past and on-going climatic change. In response to climatic change, species can move, adapt, or become locally extirpated or globally extinct. The ability to adapt is often dismissed; anthropogenic global warming is thought to occur at too fast a rate. We use the fine-scale paleomidden record of the bushy-tailed woodrat, Neotoma cinerea, from across the western United States to quantify the ability to adapt to climatic shifts of woodrats over the last 25,000 years. Previously, it has been shown that over both space and time woodrat mean population body size changes in response to climate, suggesting they have the ability to adapt in situ. We use both a northern-hemisphere ice-core record (Greenland Ice Sheet Project 2) and multiple climate proxies to develop a series of local records (tree-rings, lake cores, etc.) to (1) assess whether the N. cinerea paleomidden record is biased towards a particular temperature regime, (2) whether the ability to adapt varied across latitudes, and (3) if the woodrat paleomidden record is more strongly correlated with local to regional fluctuations versus global events. We expect a tighter correlation with regional proxies. Thus far, we find that N. cinerea are robust to climate change – including changes as drastic as 4°C within a 100 year interval. We find that extirpations are limited, and are restricted to geographic range boundaries. The scientific community may be underestimating the ability of species to adapt over relatively short time scales.