This photo by Lincoln P. Brower shows millions of Monarch butterflies huddled together in the fir forest in Michoacan, Mexico in which they spend the winter. The golden hue is created by the Monarchs. Immediately adjacent is the scarred earth stripped bear by logging.
In autumn about 100 million Monarch butterflies start their migration from Canada to the south. The insects navigate according to the position of the Sun, adjusting their calculations as it appears to move across the sky.