Some crop circles are done by people as hoaxes, not all. There is a difference, tests of plants, soil etc. show unusual substances in real crop circles. Just as there are real UFO's and fakes, there are real alien crop circles and human-made ones. Research will tell you that we have enough evidence to support real crop circles and real UFO's.I believe in time, aliens will show themselves.
like i said go to the crop circle connecter and see the brilliant circles that have been happening for over 300 years!man would love to explain this but can't.i don't know why it is so unbelievable (to certain people), that we as humans are the ONLY species!!!!!!!!just like birds,snakes,monkeys etc.there are so many species of each thing!!!!!!!