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.
It is estimated that there are at least 600,000 black bears in North America. In the United States, there are estimated to be over 300,000 individuals. However, the Louisiana black bear (Ursus americanus luteolu) and Florida black bear (Ursus americanus floridanus) are unique subspecies with small populations.t is estimated that there are at least 600,000 black bears in North America. In the United States, there are estimated to be over 300,000 individuals. However, the Louisiana black bear (Ursus americanus luteolu) and Florida black bear (Ursus americanus floridanus) are unique subspecies with small populations.