Sensory imprinting produces life-long attachment to environmental features experienced during a critical period of early development. Imprinting of this kind is highly conserved in evolution and is an important form of adaptive behavioral plasticity [1]. The nematode Caenorhabditis elegans undergoes such adaptation to new environments through imprinting: attractive odorants, when present during the first larval stage, produce life-long olfactory imprints that enhance attraction and egg-laying rates in the adults [2]. Here I report evidence that the olfactory imprint can be transmitted to the next generation. If the imprint is generated successively over more than four generations, it is not just transmitted through one further generation, but rather, it is stably inherited through many following generations. While the transient nature of the inheritance suggests the existence of resetting mechanisms, stable trans-generational inheritance of the kind reported here raises the possibility that a behavioral alteration produced by an environmental change might be genetically assimilated after a limited number of generations.
