  Mounting experimental and theoretical evidence suggests that coherent quantum
effects play a role in the efficient transfer of an excitation from a
chlorosome antenna to a reaction center in the Fenna-Matthews-Olson protein
complex. However, it is conceivable that a satisfying alternate interpretation
of the results is possible in terms of a classical theory. To address this
possibility, we consider a class of classical theories satisfying the minimal
postulates of macrorealism and frame Leggett-Garg-type tests that could rule
them out. Our numerical simulations indicate that even in the presence of
decoherence, several tests could exhibit the required violations of the
Leggett-Garg inequality. Remarkably, some violations persist even at room
temperature for our decoherence model.
