Understanding potential future impacts of climate warming on our planet is a major concern facing our society today.  Understanding the relationships of all organisms in the Tree of Life represents another primary objective of the scientific community.  There are multiple ways that the climate warming objective can be addressed, including development of models to forecast future outcomes, and examination of fossil localities that existed under past warm climates.  Deciphering the Tree of Life must include an understanding of evolutionary history derived from the fossil record.  Our study added information to both of these critical issues through an investigation of a 48 million year old fossil locality, known as Giraffe Pipe locality, which represented a freshwater lake that existed near the Arctic Circle under Greenhouse conditions.

We documented exquisitely preserved microfossils contained within 70 meters of rock remains at the Giraffe Pipe fossil locality, and used them to chronicle a high resolution history of the waterbody in order to evaluate the impact of the warm climate on lake development, biodiversity and biogeography in this freshwater Arctic setting.  One key finding was that the waterbody was thriving with aquatic organisms representing multiple lineages of the Tree of Life.  We further documented an array of organisms that today are restricted to warm subtropical or tropical regions, including ones representing algae, sponges, as well as remains of palm trees. These findings imply that warm water organisms would likely be able to migrate, grow, and most likely thrive under future warming scenarios.

The history of how the lake changed over thousands of years was further inferred from the fossil remains.  The suite of changes, including shifts in water depth, acidity, amount of organic matter and nutrient content, will serve as an important baseline for additional investigations of the core material involving other scientific disciplines.

In addition, much information was documented with respect to the evolutionary histories of the lineages of organisms found in the rock matrix, including descriptions of numerous new organisms.  We have learned that the morphologies of many organisms have remained stable over the last 48 million years, while others have significantly changed. Changes in the sizes of organisms have also been interpreted for many species, which can also be used to investigate potential shifts in community structure if similar changes occur in the future. Many of our findings represent the oldest known records for multiple groups of organisms, which can be used as age constraints linking evolutionary history to the geologic record.  To date, specimens from the Giraffe locality have been used to help interpret molecular data for organisms known as synurophytes, diatoms, sponges, and soon microbes that are at the base of the lineage that includes humans.

In addition to the P.I. and grant associates, the work supported seven undergraduate researchers and yielded 11 publications, seven conference presentations and an extensive online database. Lastly, material from this project was used to develop a presentation, Ancient Climates, which has and will continue to be given in public settings.

Last Modified: 12/31/2021
Modified by: Peter A Siver