Reference: http://www.historylink101.com/lessons/farm-city/story-of-farming.htm
More facts about people.
More human facts
Prairie dogs, those little pups popping in and out of holes on vacant lots and rural rangeland, are talking up a storm. They have different "words" for tall human in yellow shirt, short human in green shirt, coyote, deer, red-tailed hawk and many other creatures.
LFA stands for Low Frequency Active sonar, a technology used by submarines to "see." Unfortunately even one hundred miles from the source of a LFA source animals experience the equivalent of decompression sickness, killing every dolphin, porpoise, orca, and whale within 100-300 miles, depending on the decibal. It's no good for humans either.
Humans are the only primates that don't have pigment in the palms
Another fact