Honey bees around the globe are disappearing and nobody knows why - maybe it is due to bloodsucking mite called varroa - pictured above. One-third of US honey bees were wiped out last year. Bees are crucial for the pollination of 90 major crops. Albert Einstein is claimed to have said that if honey bees disappeared the human race had 4 years until it to became extinct. Commenter AndrewT points out this may well be apocryphal.
In addition there is the possibility that wild bees may substitute as pollinators if honey bees disappear.
An intriguing story and the subject of a book.