EVALUATING POLLEN MALFORMATIONS AS INDICATORS FOR PAST ENVIRONMENTAL STRESS

High frequencies of fossilized pollen malformations from woody seed plants are thought to indicate environmental stress during the end-Permian crisis. However, abnormality production rates are not well understood in modern unstressed trees. It is also unclear whether some tree lineages may be more prone to producing malformations than others. To answer these questions, malformation frequencies were compared between pollen yields of fifteen conifer genera sampled from living collections across the continental United States. An update regarding results of this study and its implications for the fossil record will be provided.