One complication of a study involving ancient flowers is the spatial separation of our species. Ideally, we would study natural populations of co-occurring red and white flowered relatives. However, the flower lineages that we study have persisted through millions of years of global change, including climate shift, continental drift, and habitat fragmentation, which have altered the original environments. Though the red and white flowered varieties of each genus most likely overlapped in habitat, at one time, they have since become isolated by change.
Spatial segregation of red and white flowered relatives makes it difficult to answer questions like, "Do stinky red flowers attract different pollinators than sweet-smelling white flowers?" because the environmental conditions of these two flowers are not comparable. One solution for this problem is to conduct a common garden experiment, where populations of each species are grown together in a shared garden space. This type of experiment resolves environmental disparities that might contribute to variance in results and observations. With a common garden, we can be confident that any differences in pollination or floral phenology are due to a divergence in floral strategy, rather than a product of environmental incongruities.
The Georgia Southern Botanical Gardens offer a unique opportunity to observe a common garden of living fossils! A white flowered relative of Carolina allspice, Sinocalycanthus chinensis, is an endangered species endemic to regions of China. Similarly, Illicium anisatum, the white flowered Japanese star anise, does not occur naturally outside of Japan and Taiwan. With the exception of botanical collections, these species cannot be found in the United States, making the GSBG a rare place to study the pollination strategies of these white flowers.
