Kafka, W. A.; Ohloff, G.; Schneider, D.; Vareschi, E.: Olfactory discrimination of two enantiomers of 4-methyl-hexanoic acid by migratory locust and honeybee. Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology 87 (3), pp. 277 - 284 (1973)
Scientists studying a rare population of tool-using chimpanzees have found that aging can have a profound impact on their abilities—but not all chimps decline equally.