82 Paleontology/Paleobotany (Posters): Non-Marine

FOSSIL INSECT DAMAGE ON PALEOCENE LEAVES FROM WANNAGAN CREEK, ND

Paper number: 82-6
Program: Technical Sessions
Time: 1:30 PM – 5:30 PM

Authors

Abstract

The Science Museum of Minnesota operated a quarry at Wannagan Creek, ND from 1970-1996 which produced large amounts of vertebrate material from crocodilians, turtles, champsosaurs, birds and mammals. Also found there are fossil leaves that show obvious signs of insect damage and feeding habits and most notably, a one meter section of a log that contains borings probably attributed to insects. The Wannagan Creek site (Late Paleocene Bullion Creek Formation) has been interpreted as a brackish swamp environment, yet only 3 fossilized insects occur from this site. Of interest to the authors is why the fossil record of arthropods is so sparse at this locality when damage to the flora and the paleoecological record suggests abundant and active insects, especially when compared to Wannagan Creek's present day eqivalent.

In 2000, the Science Museum of Minnesota received a 3 year grant from Lucent Technologies to fund a project known as the Youth Science Center Field School, which in part, involves high school students in active field research in geology and paleontology. As part of a research project, students have collected extant leaves based on types of insect damage and compared them to the Wannagan Creek flora, resulting in identifying a significant number of fossilized leaves showing evidence of insect interaction. They then attempted to collect dead insects from one meter grid sections from numerous locations with varying degrees of success. Even though insects are so abundant, the opportunity for their fossilization are rare and modern surveys can help explain why this happens. Their results and conclusions can help us to understand the lack of fossilized arthropods at this and other localities as well as show us how to determine insect interactions of the past.