Using museum specimens to refine species distribution models: The Florida Plant Diversity Project

With an estimated one billion specimens hosted in 1,600 collections in the USA, natural history museums and herbaria contain immense data on species distributions and ecology. The iDigBio portal, which currently serves data for 60 million records (and a corresponding estimate of at least 150 million specimens) grants anyone access to these specimens through a simple search engine. The scope of research questions that this resource will enable is unprecedented! Mapping biodiversity at the landscape level, organism traits, endemism or evolutionary history all are essential for conservation, ecological, phylogenetic and evolutionary studies. Florida hosts several biodiversity hotspots and is home to over 4,100 species of plants. Using, amongst other sources of data, herbarium collections, we took advantage of the historical data linked with the specimens to improve on the current methods for species distribution models. We report here new methods that can be applied to modeling using herbarium specimen data. To shift from a niche model to a species distribution model, we geographically restricted the training area of the models according to the number and location of occurrences. This study emphasizes the importance of museum collections in our ability to understand and predict future changes in biodiversity at the landscape level.