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.
Female black bears may give birth to 1 to 6 cubs (twins are most common) in January or February. Black bear cubs may be 1/250th the size of the mother bear, and are the smallest newborns, compared to their mothers, of any placental mammal. These tiny and blind cubs remain in the den with the mother and continue to grow and develop in what is described as an âexternal pregnancyâ until it is time to leave the den in the spring.