The chief of a Native American tribe was asked in the autumn if the winter was going to be cold or mild. Being a 21st century chief he had no idea, but said that it was going to be cold and told the people in his village to collect wood.
A few days later he rang the National Weather Service. "Yes, it is going to be cold," they told him, so he went back to his people and told them to collect more wood.
A week later he called again. "Is it going be a cold winter?" he asked. "Yes, very cold." So he went back and told his people to collect every bit of wood they could.
Two weeks later he called again. 'Yes," he was told, "it is going to be one of the coldest winters ever."
"How can you be so sure?" the chief asked.
The weatherman replied: "The Native Americans are collecting wood like crazy."