Fossils tell us a lot about the environment during the time they were deposited. Fossils can indicate something as important as the weather. This is because organisms live under specific conditions. An index fossil must be distinctive, abundant, and short-lived.
Matthew was suffering an anxiety attack, this is proven with his feelings of being "overwhelmed.. feelings of intense apprehension". He was experiencing shortness of breath due to how he was feeling.
Glaciers are massive bodies of ice that move across the surface of the Earth like rivers. As glaciers move they change the surface of the Earth by wearing away loose rocks and soil and depositing them somewhere else.