Spatial memory is important for animals that store food. These animals living in harsh environments rely strongly on food-stores and should have better memories to support cache retrieval and should benefit from more neurons within larger hippocampi, the part of the brain involved in spatial memory.

We found that hippocampal volume and neuron number in birds collected along a gradient from Alaska to Kansas ranked perfectly with climatic severity.

Birds from harsh northern climates had larger volumes and more neurons than those from mild southern latitudes.

Environmental pressures therefore seem to influence the brain, which may result in better survival.

Proceedings of the Royal Society B: Biological Sciences

Proceedings B is the Royal Society's flagship biological research journal, dedicated to the rapid publication and broad dissemination of high-quality research papers, reviews and comment and reply papers. The scope of journal is diverse and is especially strong in organismal biology.

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