Magnetic birefringence and dynamic light scattering measurements of orientational order parameter fluctuations at the isotropic-nematic phase transition of a bent-core liquid crystal reveal a pretransitional temperature dependence consistent with the standard Landau-deGennes mean field theory. However, the transition in the bent-core compound is more weakly first-order (T_NI-T^* ~0.4^oC), the leading Landau coefficient is ~30 times lower, the viscosity associated with nematic order fluctuations is ~10 times higher, and the density change is ~10 times lower than typically observed in calamitic (rod-shaped)liquid crystals. One consistent explanation for these anomalies is an optically isotropic phase composed of complexes of bent-core molecules. Also, we will present preliminary magnetic birefringence and density measurements at temperatures above the nematic-isotropic transistion which support the existence of such an optically isotropic clustered state.