Bouncing Back : Mexican Jumping Beans Roll Into Stores, Providing Cheap Thrills, Teaching Chaos Theory


It’s nothing they did, but Mexican jumping beans had been as scarce here as nickel candy bars. They are back in force, though, and merchants can’t seem to keep them on the shelves.

Kids are buying them. Adults are buying them. Sold three at a time in little plastic boxes (usually for 99 cents), they have leapt back into the hearts and minds and pockets of many Southern Californians.

“No doubt about it, it’s a fad item, and they came back in vogue this year,” said Steve Choate, a buyer for American Drug Stores, Chicago-based parent of 249 Sav-on drug stores.


Sav-ons in Southern California began selling the little ambulatory pods last month--and at many locations sold out within a week. Before that, they were only available locally at a half-dozen or so independent retailers and specialty chains, such as Kay-Bee Toys. The beans, a seasonal item harvested from small desert trees in Mexico, have been more widely available elsewhere in the country all along.

“We ship 3 to 5 million beans each year,” said Joy Clement of Chaparral Novelties in Alamogordo, N.M., “and their popularity remains constant. We’ve had them out every year for the last 32 years.”

Why haven’t you seen much of them here? Simple, Clement says; she hasn’t had a good distribution system in place in Southern California. Ron Miller, a novelty buyer with American Drug, said that as soon as the company hooked up with Clement (he calls her “the jumping bean lady”), he knew they had a winner.

“There’s not much you can buy at a retail store that can give you this kind of satisfaction for under a buck,” Miller said. “It’s one of the last of the low-end entertainments available in the world.

“Everybody we talked to, whether they were in their 20s, 30s, 40s or 50s, had had beans in their life,” Miller said. “Parents and older people were just as turned on as the kids. They remembered their own childhood, marveling at the movement in their hands and not understanding why. Though it’s obvious something is going on in there, I never knew until dealing in jumping beans that there was some sort of life in them.”


There’s life in there?


Yes. There’s a quarter-inch caterpillar trapped inside.

Has the SPCA been notified?

The caterpillar wants to be in there. Make a hole in the pod, and it’ll patch it back up within a couple of hours.

How does it breathe?

The shell of the pod is porous.

What does it eat?

It eats the seed inside the pod.

What does it do for water?

The jumping motion produces metabolic water at the rate of 1% of its body weight each day, which is comparable to man.


“We pee, they don’t,” said Mahlon Kriebel, professor of physiology at State University of New York at Syracuse.

What’s a professor in New York got to do with Mexican jumping beans?

He’s using the beans to teach chaos theory, a field that has revolutionized mathematics.


The life story of a jumping bean begins when an adult moth, Laspeyresia saltitans ( saltatory meaning to jump), lays an egg in the flower of the yerba de la flecha tree, Sebastiana pavoniana. The shrub is native to the Sonoran desert, particularly near the Rio Mayo in the states of Sonora and Chihuahua. The center of harvesting operations is Alamos, several hundred miles south of the U.S. border.

As the shrub’s flowers develop into seed pods, the moth eggs hatch and develop within the pods. The pod falls off with the developing larva imprisoned. The larva metamorphoses into a pupa, which remains dormant during the winter months. It emerges, through an escape hatch prepared by the larva, as a moth in spring.

The caterpillars have a very strong activity span of six to eight weeks that begins with their fall from the tree. The caterpillar moving is what makes the bean jump. And the jumping is what causes the clattering that is the bean’s natural marketing ploy when it reaches the shelf at check-out stands across the border.

“We begin shipping in July and we continue to ship through the first two weeks of September,” Clement said. “The rest of the year, people think (the beans) are dead because they’re not jumping.”


How do you know if you’ve got a real live jumping bean? Shake it. If it rattles, it’s a dud.


Kriebel, the physiology professor, has been studying the beans for years and has written several scientific papers (as yet unpublished) on the subject--including “The Jump of the Mexican Jumping Bean,” which is also the title of a video he is developing.

Temperature has a dramatic effect on how the bean jumps, and that makes it an excellent candidate for scientific study, Kriebel said. “Here is a motion that can be controlled by one parameter, drastically.

“Study the interval between jumps. When it’s periodic, they’re going tick tick tick. When they’re cooler, it looks as if they’re jumping randomly, but if you analyze the data, you see that it’s not random at all. They develop a pattern, mathematically what we call chaos.”

In chaos theory, past observations enable the observer to make short-term predictions.

“Any time you’re below this magic 62 degrees, the beans jump chaotically,” Kriebel said. “If you know the pattern, you could amaze your friends by predicting the next movement.”

That type of amazement is what he hopes will lead the beans to do no less than revolutionize the field of education.


It is a field that he and a group of fellow New York scientists see as increasingly geared toward preparing students for SAT tests and little else.

“I teach at a medical school, and over the last 25 years, I’ve seen a real fall-off in general interest biology,” Kriebel said. “Many students have not had hands-on experience with something alive. Instead, there is a fascination with computers, as if computers will ask and solve problems. All the teachers try to do now is teach for the SATs. There’s a lack of real-world activities, and we’re heading toward a monoculture.”

Kriebel and his colleagues began to look for hands-on activities that would combine various disciplines such as math, biology and physics. Using piles of popcorn to monitor earthquake phenomenon was one. The jumping beans, which exhibit circadian rhythms and are sensitive to temperature and vibrations, were another, and results of experiments could be easily replicated.

With the help of Science Kit and Boreal Laboratories in Tonawanda, N.Y., the scientists hope to see their educational project introduced in high schools and colleges by next year.


The bean made its jump to the United States from Mexico with a big push from Clement, its primary importer.

“Back in the early ‘60s, my husband was a traveling candy wholesaler,” Clement said. “One day he came home with jumping beans and said he wanted to start selling them. I told him he had rocks in his head. I’d grown up with them in the Texas Panhandle, and I didn’t see people spending money for them. The next year we were in business. It’s a very odd business, to say the least.”


Indeed. Because the jumping bean is both animal and vegetable, it’s fraught with a unique set of problems.

It’s an insect, so the population will fluctuate like any population. It’s a crop, so it’s weather dependent: If there’s too little rain, or if rain doesn’t come at the proper time, the shrubs don’t bloom--and for Clement, that’s crop failure.

“Jumping beans are always popular, but we’ve lost customers because we can’t guarantee our ability to ship every year,” she admitted.

The beans are harvested from the desert floor and shipped by Clement to the United States. They are also sold unpackaged as a curio along the border, but in Mexico itself, the jumping beans are less of a novelty.

Away from Mexico, even delivery of the beans can cause excitement. A United Parcel Service driver abandoned his truck when he decided he was carrying a rattlesnake; explosives experts were called in and a building evacuated when a shipment passing through O’Hare Airport was thought to be a ticking bomb.


Jumping beans don’t bite or explode, but they have their share of other quirks.

Light makes the pod snap back and forth. Put it on a hot plate, it’ll jump real fast. In nature, the pod’s ability to jump may allow it to move off of a hot rock or away from hot sand into the shade. “If the pod were to sit in direct sunlight, it could roast the larva inside,” Kriebel pointed out.


The pod has one rounded surface and two flat surfaces, joined at a 120-degree knife-edge, actually a common packaging angle found in nature. The larva crawls about inside the pod, weighting it asymmetrically.

Kriebel calls the “crochet hooks” on the caterpillar’s legs the “original Velcro system.” The larva can make the pod jump by jack-knifing its body and snapping it back and forth; it anchors its rear end with the hooks, stretches, bends over backward, contracts and releases. Not unlike a rubber band.

The larva is about a third lipid (a nice word for fat), a third water and a third protein. The lipid is converted into carbohydrate, the carbohydrate into an energy source. “Given the amount of lipid, we’ve calculated that the beans have the capability of doing about a million jumps,” Kriebel said. “But they turn into moths before that happens.”

In fact, the larva jumps about 500,000 times before it pupates into a chrysalis. In a cool room, the larva will jump from August to December. In a refrigerator it can remain in the larval stage until spring.

“Put them in a refrigerator, take them out in January and they’ll still be jumping,” Kriebel said. “You’ve slowed down their clock.”

Before metamorphosis, the larva makes a one-millimeter escape hatch in the shell wall. After its transformation, the adult moth pushes through the hole, abdomen first, and flies away in hopes of beginning a new generation of jumping beans. Clement believes that only the strongest survive the process, while Kriebel believes that most of the larva turn into moths.



The fact that they turn into moths is what keeps jumping beans out of the House of Humor in Costa Mesa.

“I didn’t get them in because there are bugs in them,” said owner Sharon Newberg. “First they have worms, then they become butterflies, or moths. I got one in the mail, I put it on the shelf, and forgot I put it there.

“I have costume rental. I don’t know if they’re born in there or put in there, but they eat their way out of the shell. They come out of the bean, and they eat the clothes.”

An almost universal misconception, Kriebel says.

“Larva eat clothes, moths don’t. And this moth would never lay eggs in clothes.” This far from its beloved yerba de la flecha tree, the moth won’t reproduce; here or there, it dies within a few days of emerging from the bean shell.

In any event, the U.S. deems the beans safe for importation (they’re considered nontoxic if swallowed, but please don’t).

Some retailers, such as Puzzle Zoo in Santa Monica and Teachers Supply in Long Beach, have never been squeamish about the beans, and carry them as often as supply allows.


“For the most part, Mexican jumping beans are an impulse item,” said Clement. “People don’t go to the store to buy them, but the clatter they make attracts your attention. If they’re jumping, you’re going to hear them. Making all that racket, they sell themselves.


“It really is amazing when you stop and think about their value--which is simply the curiosity that they inspire, in adults as well as children. They’re all fascinated by them.”

That includes scientists, of course. As much as they can tell us about the bean, at its core there remains a mystery.

“Maybe the beans jump to get out of the heat,” says Kriebel. “Maybe they jump to generate metabolic water. . . . They may need to jump, but we don’t know why they’re jumping. That’s why it’s such a thrill.”

What Makes It Jump?

The Mexican jumping bean is a combination of plant and animal-bean pod and caterpillar. It is formed when adult moths lay eggs in the flower of a shrub native to the Sonoran desert in Mexico.

*Bean pod: Three seeds form a pod

*Caterpillar: When it moves, the bean jumps

Did You Know

* Caterpillar is active for six to eight weeks (jumps about 500,000 times), then goes dormant during winter months.

* When it’s hungry, it eats the seed; it can breathe though porous shell.

* In the spring, it emerges as a moth through an escape hatch in the pod.