An environmentalist was giving a speech and told his audience that if we continue on our present course all life on earth will be gone in 50 years

A member of the audience jumped to his feet and cried out in panic, "What? What did you say?!"

The environmentalist solemnly repeated, "I said if we continue the way we are that every man, woman, and child on earth will be gone in fifty years."

The man sat down in relief and said, "Oh, thank God. I thought you said fifteen years."