What does the Zinsmeister Collection have to do with the extinction of the dinosaurs?

The fossils from Seymour Island represent animals that lived during both the Cretaceous and Paleogene period in the Earth's history. At the boundary between these two time periods, 65 million years ago, there was a catastrophic extinction event that resulted in the disappearance of 75% of the species on earth, including dinosaurs. The sediments on Seymour Island contain one of the best records of the time period before, during, and after this extinction. This makes the Zinsmeister Collection extremely useful for studying this period in time, including the mass extinction, and what caused it.

A concretion encasing some pieces of what is called "fish debris" - fragments of fish bones laid down at the end of the Cretaceous period.