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Green sulfur bacteria are life forms that use sun light as a main food source. They harvest the light by absorbing the sun's photons with their chlorosome system, an assembly of thousands of chlorophyll molecules. Absorption produces electronic excitation of the chlorophyll molecules, but the excitation is only short-lived (lifetime of about 1 nanosecond) and needs to be turned quickly enough into a more stable form of energy. The latter is achieved in a protein complex called the reaction center, but for this purpose the electronic excitation needs to travel from the chlorosome to the reaction center through a protein complex called the Fenna-Matthews-Olson (FMO) protein. FMO is a crucial bottleneck, acting as an energy faucet, through which the short-lived excitations need to flow in a fraction of a nanosecond. Electronic excitations are quantum phenomena highly sensitive to thermal noise. Biophysicists spend much effort to measure thermal effects on FMO electronic excitation flow. Now researchers have complemented measurements through calculations and have shown why FMO function is actually robust against thermal noise. Using a combination of classical and quantum mechanical calculations they quantified the thermal noise present in FMO (reported recently here and here), and determined that thermal noise greatly reduces quantum coherent excitation in the transport through FMO (reported here), but that does not seem to be detrimental to excitation flow. More information can be found here.