15. Mexican Jumping Beans (with video)

Were you ever intrigued as a child (or even as an adult) by Mexican jumping beans? What makes the little brown beans wriggle around and look alive?

The answer involves the Jumping Bean Moth.

The secret is that live moth larvae (caterpillars) live inside the jumping beans and cause them to “wiggle” when the caterpillars move inside. Warmth increases the movements.

In the spring, moths emerge from last year’s beans and lay eggs in the flowers of the poisonous tree Sebastiana pavoniana. Upon hatching the larva bores into a seed pod (bean) and eats out a cavity. It attaches itself to the inside walls with silk threads. It can live for months inside the pod.

Heat causes the little caterpillar to try to roll to a cooler place. Its struggles pull on the silk threads causing the seed pod to twitch.

Here’s an 18-second video showing typical movements of Mexican jumping beans.

The larva pupates inside the bean and metamorphoses into a moth. The small silvery gray-brown moth exits the bean and lives only a few days to mate and lay more eggs.

The northwestern Mexican state of Sonora, immediately south of Arizona, styles itself as the “Jumping Bean Capital of the World”. Mexicans call the beans brincadors (hoppers).

Read the prequels in this series on Monarch Butterflies and their significance for the creation/evolution controversy:
1. Insect GPS
2. Monarch Butterflies
3. Caterpillar or Butterfly—Which Was First?
4. Monarch Caterpillars
5. Morphing Monarchs
6. Changing Chrysalis
7. Emerging Monarchs
8. Butterfly vs. Caterpillar
9. Migrating Monarchs
10. Navigating Monarchs
11. Monarchs on Noah’s Ark?
12. Monarch or Viceroy?
13. Butterfly Evolution?
14. Butterfly or Moth?

Read the sequel:
16. Silk

Soli Deo Gloria.

Subscribe – Don’t miss future blog posts!
Click the sidebar’s “SUBSCRIBE” button to follow the
Bible-Science Guy Blog. You’ll automatically receive
new posts free by email. Click SUBSCRIBE NOW!

©William T. Pelletier, Ph.D.
“contending earnestly for the faith”
“destroying speculations against the knowledge of God”
(Jude 1:3; 2 Cor 10:4)
Monday February 22, 2010 A.D.

Read my February 2010 Bible-Science column
Manhood and Monogamy.

And Yahweh made the beasts of the earth after their kind, and the cattle after their kind, and everything that creeps on the ground after its kind; and Yahweh saw that it was good. (Genesis 1:25)