Ranjan Muthukrishnan of the Environmental Resilience Institute continues to work at the leading edge of research on species plasticity using high performance computer (HPC) simulations. His recent work, in collaboration with Lauren L. Sullivan, Allison K. Shaw, and James D. Forrester, takes a new look at how species are able to coexist in ecosystems without excluding each other, and how that can help ecosystems become more diverse. The group evaluated this question by expanding on a well-established ecological theory, the competition-colonization trade-off. This theory has long held that, within an ecosystem species could coexist with each other, if species that were good competitors, they were also slow to disperse to new habitats, while strong colonizers disperse with ease, but are outcompeted when good competitors show up in their habitat.
As Muthukrishnan notes, this trade-off relies on the notion that the traits that prompt these trade-offs are fixed; parent plants always produce offspring just like themselves, independent of the environment. He decided to see what would happen if they accounted for the high degree of trait plasticity exhibited by many plants, where they can make seeds of different sizes depending on the conditions where they grow. To do so, he created simulations on IU’s Big Red 2 and Big Red 3 supercomputers in order to evaluate the effect of trait plasticity on plant coexistence.