Potential for and consequences of naturalized Bt products: Qualitative dynamics from indirect intransitivities

Advances in genetic modification technology and the production of human-altered genomes have led to an array of genetically modified organisms utilized to address numerous global issues. The human need-based development of these modified organisms often presents unprecedented phenotypes which will interact with the world's existing biodiversity in unknown ways. One such example is Bt transgene crops proliferating because of their application to food security issues due to their resistance to pest insects. While threats to long term viability of Bt crop use due to resistance evolution in pests have been extensively investigated, issues regarding the effects of Bt transgene crops on existing ecosystems and the biodiversity contained therein have seen less scrutiny. In particular, the long-term dynamics in the case of a naturalized Bt product has not received the attention it deserves. Here we note that the ecosystem structure emerging from a naturalized Bt crop is, qualitatively, an intransitive loop. Based on this structure we develop a simple ecosystem model showing that the intransitive nature of the system has potential to facilitate long term persistence of naturalized Bt transgenes by shifting community dynamics.