Palynology (Gr. palynos, dust) is the study of spores and pollen grains. Spores and pollen grains have a number of morphological and ultrastructural features. These palynological features have provided a wealth of characters that have been important in inferring phylogenetic relationships of plants. In addition, the features of spores and pollen grains can often be used to identify a particular plant taxon. For this reason, palynological studies are used extensively to examine the fossil record, a field called paleopalynology.

The identity, density, and frequency of pollen grains at a particular stratigraphic level can give information as to the plant species present at that time and place. Paleopalynological studies are thus used to determine plant community structure and to gauge, by extrapolation over time, shifts in climate.

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