A larger hippocampus is associated with longer-lasting spatial memory

Volumetric studies in a range of animals (London taxi-drivers, polygynous m ale voles, nest-parasitic female cowbirds, and a number of food-storing bir ds) have shown that the size of the hippocampus, a brain region essential t o learning and memory, is correlated with tasks involving an extra demand f or spatial]earning and memory. In this paper, we report the quantitative ad vantage that food storers gain from such an enlargement. Coal tits (Paros a ter) a food-storing species, performed better than great tits (Paros major) , a nonstoring species, on a task that assessed memory persistence but not on a task that assessed memory resolution or on one that tested memory capa city. These results show that the advantage to the food-storing species ass ociated with an enlarged hippocampus is one of memory persistence.