How often do whales clean their ears? Well, never. And so, year after year, their ear wax builds up, layer upon layer. According to a study published Monday, these columns of ear wax contain a record of chemical pollution in the oceans. The study used the ear wax extracted from the carcass of a blue whale that washed ashore on a California beach back in 2007. Scientists at the Santa Barbara Museum of Natural History collected the wax from inside the skull of the dead whale and preserved it. The column of wax was almost a foot long. "It's kind...