Are you wondering what this macaw is doing on this clay bank in Peru? Scientists used to think that they ingested the clay to absorb the poisonous naturally occurring tannins in the plants they eat. However, they now discovered there's a connection between this clay-eating and the fact that the Western Amazon Basin is lacking in salt. As a paper in the Proceedings of the National Academy of Sciences explains, sodium supply varies by region. The farther an area is from the ocean, the more its rain may lack salt. Plus, in inland areas with high rainfall, sodium may leach out of the soil. So Brightsmith and his research team are testing the importance of salt intake in the overall health of macaws. (Smithsonianmag.com).