A new study indicates that Americans gained up to 15 IQ points after the addition of iodine to salt became mandatory. In an effort to prevent goiter related to iodine deficiency, authorities ruled that iodine be added to U.S. salt products in 1924. The iodine, in addition to eliminating goiter, appears to have had an unexpected result: smarter Americans.
At peak lactation a black bear cub consumes about 30 ounces of milk a day, and a brown bear cub takes about 45 ounces. Thatâs per cub, so a mom with a litter of two or three cubs could be producing three or four quarts per day â a difficult metabolic feat to sustain.
One study estimated that there were 750,000 to 900,000 black bears distributed across North America, and their numbers have been growing. A recent study in the Journal of Wildlife Management documented 59 fatal black bear attacks, resulting in 63 human deaths, in the United States and Canada from 1900 through 2009. And the scientists learned that many of our assumptions about bear dangers are wrong.