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On the Cover: Why the leaves of many woody species turn red during autumn has long puzzled biologists because it is unclear what effects the accumulation of anthocyanins may have on leaf function. In Feild et al. (pp. 566–574) it is shown for red-osier dogwood (Cornus stolonifera) that anthocyanins form a pigment layer in the palisade mesophyll layer that decreases light capture by chloroplasts. In particular, chlorophyll a fluorescence measurements revealed that maximum photosystem II photon yield of red (anthocyanic)-senescing leaves recovered rapidly from a high light stress treatment whereas senescing leaves lacking anthocyanins failed to recover after 6 hours of dark adaptation. These data provide evidence that optical masking of chlorophyll by anthocyanins reduces the risk of photo-oxidative damage to leaf cells from senescing leaves, which otherwise may lower the efficiency of nutrient retrieval prior to leaf fall (photograph of autumn leaves at Harvard Forest by David W. Lee).