Giant earwax plugs tell the life stories of blue whales.
You know what they say about huge animals, don't you? They have huge balls... of earwax! Take blue whales, for example: according to this study, they carry around 10-inch long plugs of earwax. The earwax accumulates in concentric layers over the entire lifetime of the whale, with the oldest layers towards the center and the newest closest to the skin (see figure below). And because earwax is hydrophobic, it can absorb fat-soluble compounds, including some hormones and pollutants. These two p