The Incredible Hummingbirds

To Brazilians they're beija flores - flower kissers; to Cubans zumzum - their wings hum at 80 beats a second. They can fly backwards, must feed about every ten minutes, and have brilliant iridescent colours. No wonder they fascinate People: some enthusiasts even give them shower baths, cut their toe-nails, and analyse their amazing flight by filming in ultra-slow motion.