Magnetofossils

When magnetotactic bacteria (MTB) die their magnetic particles can be preserved in sediments as magnetofossils. The magnetic properties of magnetofossils makes them easily identifiable in bulk sediments using magnetic measurements. Magnetofossils are exciting biomarkers for these reasons and because they can record life in sediments which biological remains are not always preserved. Although I study living MTB, a much larger part of my PhD involves magnetofossils from a global warming event 56 million years ago. I use a combination of scanning electron microscopy, transmission electron microscopy, and rock magnetic measurements to determine and characterize changes in MTB assemblages during this event. My work is made stronger by collaboration with experts in micromagnetic modeling, statistics, and benthic foraminfera. This work allows me to better understand changes in marine oxygen and nutrient supply during periods of rapid planetary change.


Publications

Wagner, C. L.., Lascu, I., Lippert, P. C., Egli, R., Livi, K. J. T., & Sears, H. B. Diversification of iron-biomineralizing organisms during the Paleocene-Eocene Thermal Maximum: Evidence from quantitative unmixing of magnetic signatures of conventional and giant magnetofossils. Paleoceanography and Paleoclimatology, 36, 1-25 e2021PA004225. https://doi.org/10.1029/2021PA004225.

Here’s a write-up that summarizes our findings: https://attheu.utah.edu/uncategorized/microscopic-fossils-record-ancient-climate-conditions/.

Wagner, C. L., R. Egli, I. Lascu, P.C. Lippert, K. Livi, H.Sears. In situ identification of   giant, needle-shaped magnetofossils in Paleocene-Eocene Thermal Maximum sediments. Proceedings for the National Academy of Sciences. doi.org/10.1073/pnas.2018169118.

If you are not keen on reading the paper, here are a couple write-ups that summarize our findings:

https://attheu.utah.edu/uncategorized/magnetofossils/
https://www.smithsonianmag.com/blogs/national-museum-of-natural-history/2021/02/01/new-way-study-magnetic-fossils-could-help-unearth-their-origins/


Presentations

Wagner, C.L., P.C. Lippert, I. Lascu, P. Parlanti, R. Polson. Searching for magnetic needles in marine haystacks: Promise and progress with in situ visualization of magnetofossils in marine sediment chips. 13th Annual FIB SEM Meeting, April 29th, 2021. Virtual Talk.

Wagner, C. L., I. Lascu, P.C. Lippert, R. Egli, K. Livi, H. Sears. Diversification of iron-biomineralizing organisms during the Paleocene-Eocene Thermal Maximum: Evidence from quantitative unmixing of magnetic signatures of conventional and giant magnetofossils. Global Change and Sustainability Center Symposium, March 2021. Virtual Poster. 

Wagner, C. L. Morphological variation of magnetofossils from the Paleocene-Eocene Thermal Maximum: Measurement and paleoenvironmental implications. PhD Thesis Defense, February 5th, 2021. Virtual Public Talk. Recording available upon request.

Wagner, C.L., R. Egli, I. Lascu, P.C. Lippert, K. Livi, H. Sears. Searching for magnetic needles in marine haystacks. 2021 Virtual MagIC Workshop and Meeting. Invited Virtual Talk. https://www.youtube.com/watch?v=I91V0N_mWW4

Wagner, C. L.., I. Lascu, P.C. Lippert, K. Livi, H. Sears, R. Egli. Magnetic unmixing of  conventional and giant coastal marine magnetofossils during the Paleocene-Eocene Thermal Maximum. American Geophysical Union Fall Meeting, December 2020. Virtual Talk.

Wagner, C. Magnetotactic Bacteria as Biomarkers. National Museum of Natural History Department of Mineral Sciences, August 2019. Talk.

Wagner, C., I. Lascu, and P.C. Lippert. Preliminary FORC-PCA on Paleocene-Eocene Thermal Maximum Sediments from Wilson Lake, New Jersey. Institute for Rock Magnetism Santa Fe, June 2019. Poster. 

Finley, H., C. Wagner, and P.C. Lippert. Magnetic Measurements of Environmental Change Across the Paleocene-Eocene Thermal Maximum at Bass River, New Jersey. University of Utah Geology and Geophysics Poster Session, April 2019. Poster.

Wagner, C., P. C. Lippert, P. Stassen, R. Speijer, E. Thomas. Magnetofossil, Magnetic Particle, and Microfossil Assemblages in a Subtropical Coastal Environment: Environmental Change Across the Paleocene-Eocene Thermal Maximum. University of Utah Geology and Geophysics Poster Session, April 2019. Poster.

Wagner, C., P. C. Lippert, P. Stassen, R. Speijer, E. Thomas. Magnetofossil, Magnetic Particle, and Microfossil Assemblages in a Subtropical Coastal Environment: Environmental Change Across the Paleocene-Eocene Thermal Maximum. Global Change and Sustainability Center Symposium, February 2019. Poster.

Wagner, C., P. C. Lippert, P. Stassen, R. Speijer, E. Thomas. Magnetofossil, Magnetic Particle, and Microfossil Assemblages in a Subtropical Coastal Environment: Environmental Change Across the Paleocene-Eocene Thermal Maximum. International Meeting on Magnetotactic Bacteria, September 2018. Poster.

Wagner, C. Magnetotactic Bacteria: Journey from the Modern into the Past. Utah Friends of Paleontology monthly meeting. Invited Talk.

Wagner, C. Magnetotactic Bacteria: Using Magnetoreception to Survive Microenvironmental Disasters.  Society for Advancement of Chicanos/Hispanics and Native Americans in Science meeting, October 2017. Invited Talk.          

Wagner, C. and P. Lippert. Environmental Change in a Neritic Setting Before, During, and After the Paleocene-Eocene Thermal Maximum: Insights from Magnetofossil and Microfossil Assemblages, Climatic and Biotic Events of the Paleogene conference, September 2017. Poster.

Wagner, C. and P. Lippert. Environmental Change in a Neritic Setting Before, During, and After the Paleocene-Eocene Thermal Maximum: Insights from Magnetofossils and Microfossil Assemblages, Institute of Geology and Geophysics (Beijing, China), July 2017. Invited talk.  

Wagner, C. and P. Lippert. Environmental Change in a Neritic Setting Before, During, and After the Paleocene-Eocene Thermal Maximum: Insights from Magnetofossils and Microfossil Assemblages, Peking University, (Beijing, China), July 2017. Invited talk.  

Wagner, C. and P. Lippert. Relating Magnetotactic Bacteria and Microfossil Assemblages in Coastal Environments to Environmental Change Before, During, and After an Abrupt Global Warming Event, Department of Geology and Geophysics Student Poster Session, May 2017. Poster.   

Wagner, C. and P. Lippert. Relating Magnetotactic Bacteria and Microfossil Assemblages in Coastal Environments to Environmental Change Before, During, and After an Abrupt Global Warming Event, Rocky Mountain GeoBiology Symposium, April 2017. Poster. 

Wagner, C. and P. Lippert. Relating Magnetotactic Bacteria and Microfossil Assemblages in Coastal Environments to Environmental Change Before, During, and After an Abrupt Global Warming Event, Global Change and Sustainability Center Symposium, February 2017. Poster. 

Lippert, P., V. Taylor, S. Bohaty, C. Wagner, C. Xuan, and P. Wilson. The demise of a diverse magnetofossil assemblage across the Eocene-Oligocene Transition in a Northwest Atlantic sediment drift, American Geophysical Union Fall Meeting, December 2016. Invited Talk.


Please feel free

to reach out!

Contact information:

Courtney Wagner, Ph.D.

Peter Buck Postdoctoral Fellow

Smithsonian Institution, NMNH

courtneywagner.geo@gmail.com

%d bloggers like this: