Plantas fósiles e inferencia paleoclimática: Aproximaciones metodológicas y algunos ejemplos para México

Paleobotany research has developed multiple analytical frameworks using plant macrofossils as a tool for paleoclimate inference. These frameworks can be broadly divided into two groups: the taxon independent approach (TIA) and the nearest living relative (NLR). The TIA studies climate-driven phenotypic variation in extant plants and extrapolates the relationship between climate and structure to make paleoclimatic inferences. The NLR, on the other hand, relies on the taxonomic identification of the species in fossil assemblages to assign them the climatic tolerances of their nearest living relatives. Both frameworks have proven to be useful but have intrinsic flaws due to the nature of the data used and the particular methods employed. Our target here is to highlight the significance of these frameworks, but also to point out that they do not always provide unequivocal paleoenvironmental data, which is the result of differences in both scale (geographic, temporal and taxonomic) and taphonomical processes. Here we illustrate some of the advantages and flaws of both frameworks using three examples of paleoclimate inference for some Mexican localities. In this paper we briefly review as well some of the relevant research relating leaf and wood structure to environmental variation that has served as the foundation for the field.