The smell of mouse mothers' food influences the olfactory anatomy of their pups, and primes them to prefer the same flavours as their mothers.

Josephine Todrank at the University of Colorado, Denver, and her colleagues studied lines of mice in which select olfactory sensory neurons that responded to smells such as cherry or mint were tagged with the gene for green fluorescent protein. The mothers were given scented food while either gestating or nursing their litters, or during both phases. When their pups were tested at 20 days old, fluorescence revealed larger glomeruli — bundles of synapses — formed by neurons specific to the smells added to their mother's food. Pups also preferred the smells of the food their mothers ate.

Such preferences could predispose animals to choose familiar and safe foods, although in humans they could backfire to plant the seed of preference for alcohol or unhealthy foods, the authors say.

Proc. R. Soc. B doi:10.1098/rspb.2010.2314 (2010)