How doth the little busy bee Improve each shining hour And gather honey all the day From every opening flower. -- Isaac Watts (1674-1748)
Isaac Watts was wrong. Some bees are downright lazy. But it took the modern technology of the bar code to prove that the British poet's moral tale for children was, well, a little on the flattering side for the bees.
It was the late 1980s. Entomologist Stephen Buchmann of Arizona's Carl Hayden Bee Research Center was studying the pollination patterns of the popular Italian honeybee, Apis mellifera ligustica.
The problem was that one bee looks much the same as another; keeping track was almost impossible. So Dr. Buchmann thought of bar codes -- after all, if they can keep tabs on the 40,000-odd products in the grocery store, surely they can track a few dozen bees.
The effect, Dr. Buchmann says, would be "like having them punch tiny time clocks."
So Dr. Buchmann turned to Intermec Technologies Corp. of Everett, Wash., one of the world leaders in bar-code technology. Researcher Sprague Ackley invented a new bar code just for the bees -- one so tiny it could be placed on a bee's back without disturbing its ability to fly or to gather pollen.
At the time, Mr. Ackley says, it was the smallest bar code ever printed -- just 25 millimetres by 13 millimetres. (Even tinier bar codes are now used to mark the components of electronic devices, Mr. Ackley says.)
To make sure his bees punched their time clock, Dr. Buchmann designed a special entrance to the hive so that the bees were forced to display their backs to a laser reader.
"Up until that time we had very limited information about how many foraging trips a bee makes per day as they age, or on different crops," Dr. Buchmann says. After the bar-code research, "for the first time we had little dossiers on individual bees."
And -- poets like Watts notwithstanding -- the results were surprising. "Some bees would make four trips a day and other bees were making over 20," he says. "There were Type As and Type Bs."
Dr. Buchmann is now thinking of tagging bees with tiny radio transmitters. The so-called radio-frequency identification (RFID) technology is the latest extension of the common bar code, which recently reached its 25th anniversary.
The era of the bar code began in Troy, Ohio on June 26, 1974. A 10-pack of Wrigley's Juicy Fruit chewing gum was the first item to be scanned in a supermarket -- chewing gum that is now in the Smithsonian Institution's National Museum of American History.
The gum purchase was made in the full glare of a publicity machine, says Smithsonian curator David Allison. "It was a big deal," he says. "For [bar codes]to be successful, it required an incredible agreement between people who generally didn't agree -- distributors, growers, retailers. Getting publicity was part of the game."
That first pack of gum bore a Universal Product Code, the standard 12-digit bar code we have all come to take for granted. But there are at least a half-dozen other forms of bar code for specialized purposes, including some that can contain more than a kilobyte of data in letters as well as numbers.
The first bar code was patented in 1929 by an Westinghouse engineer named John Kermode. It was invented, says Mr. Ackley, as a way for the company to keep track of electricity bills but there is no evidence it was ever used.
Later, primitive bar-code systems identified rail cars and library books in the 1960s, "but they were very limited in scope," he says. "The first application that was real was the UPC symbol in supermarkets."
Dr. Allison, who mounted a Smithsonian exhibition to mark the 25th anniversary of the Universal Product Code, says it has revolutionized some key aspects of society, such as how people shop and where they shop.
The modern "big-box" stores, for instance, would not be possible without the bar code, he says. And the modern supermarket has expanded, both physically and in terms of product selection, only because bar codes made it possible to keep track of more goods.
In the 1970s, Dr. Allison says, a typical supermarket would have carried 9,000 products. It would have closed every so often to take inventory, box by box and can by can. Today, a typical store has 40,000 products. When the product's bar code is scanned at the checkout, a central computer checks the price and flashes it back to the cash register. Changing prices is easy and so is keeping track of what's on the shelves.
According to the Uniform Code Council Inc. (UCC), which administers the bar-code system in the United States, research shows bar codes have had an enormous impact.
The committee that proposed the UPC system estimated in 1975 it would save the grocery industry $1.43-billion (U.S.) a year, the UCC says. But net benefits annually are now about 5.7 per cent of grocery sales -- or $17-billion a year, the council says.
Mr. Ackley estimates that bar codes are still only used in perhaps 15 per cent of the places they could be.
The future of bar codes is not so limited. Dr. Allison of the Smithsonian foresees the day when microwave ovens will read a bar code on a frozen meal and cook it automatically, or when refrigerators will track best-before dates printed on groceries.
BARS AND SWIPES FOREVER
The standard bar code -- the Universal Product Code -- contains a 12-digit number, "spelled out" in vertical bars and spaces and repeated in human-readable figures. The first six digits identifies the manufacturer; the next five identify the product. The final digit is what's called a "check digit," obtained by manipulating the first 11.
The bar code relies on the relative widths of its spaces and bars. The thinnest bar (or space) is one unit wide and the widest is four units. Combinations of spaces and bars in different widths represent numbers.
So, for instance, a figure 3 is given in a UPC symbol by a one-unit space, a four-unit bar, a one-unit space and a one-unit bar.
There's one complication: Although the pattern is the same -- 1-4-1-1 for a 3 -- numbers on the right of the bar code reverse the roles of spaces and bars. So, if a bar code is 003000 000300, the figure 3 on the left is space-bar-space-bar, while the one on the right is bar-space-bar-space, but the relative widths will be the same.
Separating the two sides will be a five-element code, all single units, consisting of a space, a bar, a space, another bar and another space.
Each UPC symbol also starts and stops with a bar-space-bar code (all single units).
There's one more complication: Many grocery items use what are called zero-suppressed numbers, in which four zeroes are removed. These eight-digit numbers are used for small items, where space is at a premium. Michael Smith is a Toronto science writer.