Mountains and species dynamics
For a long time, researchers have recognized a relationship between topography and species diversity. Regions with high topographic gradients tend to have more species, in part because these regions have more landscape diversity and more potential habitats for species to occupy. We know that this pattern persists across continents today and is found among many groups of animals including non-volant mammals (i.e., not bats). We do not, however, know the degree to which this pattern would have existed in now-extinct groups of mammals. This knowledge-gap, is partly driven by lower preservation potential of remains in regions of higher topographic relief and resulting lack of fossils from higher elevations. |
Fossils on mountains
My field-based research aims to fill in this gap in our knowledge and focuses on collecting fossils from high elevation sites in northwestern Wyoming. These sites are all from the Eocene (56-33 million years ago), a time characterized by much higher global temperatures. During the Eocene, WY was home to numerous animals that are adapted to much warmer and more moist temperatures - animals we would only find in the tropics today. This fauna includes primates, which today are threatened by habitat loss due to deforestation and climate change. Some species of mammals (e.g., some rodents) are able to shift their home ranges upwards in elevation along mountains in response to habitat loss demonstrating that higher elevations can and do play a role in allowing species to survive periods of climate change. My research on high elevation sites in the Eocene explores faunal dynamics around mountain ranges to see whether species in the past used mountains in a similar way as we see in some modern taxa.
My field-based research aims to fill in this gap in our knowledge and focuses on collecting fossils from high elevation sites in northwestern Wyoming. These sites are all from the Eocene (56-33 million years ago), a time characterized by much higher global temperatures. During the Eocene, WY was home to numerous animals that are adapted to much warmer and more moist temperatures - animals we would only find in the tropics today. This fauna includes primates, which today are threatened by habitat loss due to deforestation and climate change. Some species of mammals (e.g., some rodents) are able to shift their home ranges upwards in elevation along mountains in response to habitat loss demonstrating that higher elevations can and do play a role in allowing species to survive periods of climate change. My research on high elevation sites in the Eocene explores faunal dynamics around mountain ranges to see whether species in the past used mountains in a similar way as we see in some modern taxa.
Carter Mountain is one of the high elevation regions that I collect fossils in. This mountain is a 30 mile-long ridge just southwest of Yellowstone National Park and preserves a diverse fauna from about 48 million years ago. I have been working at these sites since 2016. (Photo by J. Groenke, 2017)
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Aycross Formation is one of the geological formations that preserves a range of environments from higher elevations to mid elevations to foothills. These sites are located in the southwestern corner of the Bighorn Basin. I have been working at these sites with my collaborators Chris Kirk and Ben Rodwell since 2018.
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Featured Publications
Euarchontans from Fantasia, an upland middle Eocene locality at the western margin of the Bighorn Basin
Lundeen and Kirk, 2023
https://doi.org/10.1016/j.jhevol.2022.103310
Lundeen and Kirk, 2023
https://doi.org/10.1016/j.jhevol.2022.103310