Our findings indicate that the amount of shrinkage is driven by variation in leaf area, leaf thickness, evergreenness, and woodiness and can be reversed by rehydration. The amount of shrinkage may also be a useful trait related to ecologically and physiological differences in drought tolerance and plant life history.

Diverse and abundant Middle and Late Triassic elasmobranch ichthyoliths (microscopic shark teeth and scales) coexisting with conodonts, ammonoids, and bivalves were recovered from carbonates of the Pardonet, Baldonnel, Ludington, and Liard formations in the Peace River area of British Columbia. These faunas provide an excellent biostratigraphical framework for Triassic strata. Results from this study demonstrate that ichthyoliths can be used in basin analyses to date and correlate strata. The following summarizes the main achievements of this project. 1. Systematic description and illustration of Triassic elasmobranch ichthyoliths include seven species of teeth and nineteen new form genera and fifty-three new form species of scales. 2. Ichthyolith distributions consist of distinct faunal assemblages for the Ladinian, Upper Carnian, and Middle Norian. The Carnian/Norian boundary is marked by the disappearance of many Ladinian and Carnian elasmobranch species. In the Middle Norian, elasmobranch faunas reached a new peak of diversity and abundance. 3. A provisional ichthyolith zonation for the Middle and Upper Triassic is proposed for the Peace River area. The sequence of coeval conodonts and (or) ammonoids indicate that the Coniunctio aequirugosa ichthyolith Zone is Ladinian, the Synechodus multinodosus ichthyolith Zone is Upper Carnian, and the Synechodus incrementum ichthyolith Zone is Lower and Middle Norian. 4. New approaches to ichthyolith identification include recognizing diagnostic characteristics of scale and tooth bases, and using binomial, form, and utilitarian taxonomic systems. 5. Interpretations of histological and morphological features of elasmobranch teeth suggest that more derived neoselachian species than were originally known are present in the Triassic.

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