Ecology flag

The Ecology flag was created by cartoonist Ron Cobb, and was published for the first time in October 25, 1969. The flag was patterned after the flag of the United States, and had thirteen stripes alternating green and white. Its canton was green with a yellow Theta. It originally had a symbol that was a combination of the letters "E" and "O" taken from the words "Environment" and "Organism", respectively. Later flags used either a Theta because of its historic use as a warning symbol, or the Peace Symbol. Theta would later become associated with Earth Day.

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