Mexican jumping bean


Mexican jumping beans are seed pods that have been inhabited by the larva of a small moth and are native to Mexico. The "bean" is usually tan to brown in color. It "jumps" when mildly heated. They are from the shrub Sebastiania pavoniana, often also referred to as "jumping bean". However, they are not related to actual beans, but rather to spurges. The beans are considered non-toxic but are not generally eaten.
After the moth-laid egg on the plant hatches, the larva eats away the inside of the bean and attaches itself to the inside of the bean with silk-like thread. The larva may live for months inside the bean with varying periods of dormancy. If the larva has adequate conditions of moisture and temperature, it will live long enough to go into a pupal stage. In the spring, the moth forces itself out of the bean through a round "trap door", leaving behind the pupal casing. After its metamorphosis, the small, silver and gray-colored moth lives for no more than a few days.

As a novelty

When the bean is warmed the larva will move to eat, pulling on the threads and causing the characteristic hop. Leaving the beans in a heated environment for more than a couple of hours can easily kill them.
The beans become energetic when a person holds them in the hand for a few minutes. The beans also appear to be a very slight shade of green on the side. When shaken near one's ear, a rattle is heard. When its hardened shell makes a softer rattle, this means that the larva has either died or entered the pupal stage.

Care and storage

Beans should be stored in a cool, dry place.
Beans require periodic rehydration, mimicking the monsoon weather of their native Mexico. To rehydrate the beans, they need to be soaked, but not submerged, for about three hours in chlorine-free water once or twice a month.