ABSTRACT

Most plant species include somewhat isolated to completely isolated populations that are established with low numbers of founders introduced in different geometric patterns. Plants colonize remote habitats in a wide variety of ways: one-seeded fruits blown on the wind, a seed bank stimulated to grow by the opening of a canopy, a bat fl ying over a forest defecating single seeds, concentrated multi-seed deposition in feces, and the transport of multi-seeded fruits on animal coats are just a few examples of means of dispersal that bring about a broad range of numerical and spatial patterns by which species are introduced to unoccupied habitats. Populations that differ in founder number and spatial establishment pattern are likely to be on the increase as our ecosystems become more fragmented, and where climate change may be driving the migration of populations. However, we lack tools with which to analyse how number and patterning of colonizers interact with other varying founding characteristics (such as the genetic diversity of founders, population growth rates, and rates of seed production) to affect population growth and genetic diversity retention. As we consider these issues below, we refer to these types of interactions as “spationumeric founding effects.”