Miss Elisabetta Canteri, David Nogués-Bravo, Niels Martin Schmidt, Hans Redlef Siegismund, Rasmus Heller, Mikkel Stelvig, Damien Fordham
The sizes, shapes and internal structures of the ranges of species are the result of demographic processes (e.g. population growth, dispersal, colonization and extinction) responding to spatiotemporal variation in abiotic and biotic processes. Until recently, researchers have tended to focus more predominantly on the correlates of the contemporary structure of geographic ranges, rather than looking to the past to unlock the mechanisms responsible for species’ range shifts. We are investigating the long-term processes responsible for the contemporary distribution of the muskox (Ovibos moschatus), which is a large herbivore living in the Arctic biome. The geographic range of muskox today is small compared to what it was in the late Pleistocene. Native populations are currently distributed only in Canada and Greenland and re-introduced populations are distributed in Russia and Alaska (US). The reasons for the historic range contraction are unclear, but include climate and land-use change, over-exploitation and their interactions. In this project we are putting the “dead to work”, using fossils and ancient DNA (in addition to contemporary DNA) to continuously reconstruct the range dynamics of muskox over the last 21,000 years. Process-based ecological models are integrated with high temporal resolution paleoclimate and land-use data, dynamic demographic simulations of Neolithic human abundance and inferences of prehistoric population change for muskox from fossils and DNA. Doing so is allowing us to develop a stronger understanding of the processes by which past global change is likely to have influenced the rate and extent of range contraction for muskox since the last glacial maximum. Specifically, we are addressing two primary questions: 1) Which processes (e.g. climate, human harvesting, land-use change or their interaction) caused the contraction and fragmentation of the geographic range of the muskox, and did these differ through time? 2) Is the present-day native range of the muskox located at the core or towards the periphery of its historical range? By understanding how the range of the muskox changed through time and which processes have been driving its distribution, we aim to better inform on the conservation of the species.
Bio to come