Moths' Open-Weave Cocoons Adapted to Handle Heavy Forest Rains

Some clever caterpillars in the rain forests of Peru have found a way to mitigate the danger of drowning in their cocoons. They weave nets so that water can easily drain out. ©From the video “Mind-blowing Cocoon in a Rain Forest,” Smarter Every Day.

In the rain forests of Peru, the average annual rainfall measures 79 inches. That not only creates lush, green jungles filled with a diversity of life but dangerous environments, too—especially if you’re a caterpillar aspiring to become a moth.

Most caterpillars construct tightly knit coverings in out-of-the-way places in which to undergo their transformations. However, this type of cocoon subjects the moth to the risk of drowning in its own shelter if water should seep into the top and begin to collect at the base. But some clever urodid moths have found a way to mitigate that danger. They weave net-like cocoons so that water easily drains out.

Peru is home to 5 million indigenous people representing 55 distinct ethnicities speaking 48 languages. It’s also the ninth most biodiverse country in the world, with 7 percent of known animal species.

Watch the short clip below, titled A Ridiculously Awesome Cocoon, taken from the video series Smarter Every Day. The photographic shots of this mesh cocoon not only encourage us to seek the beauty of nature in small places but also in the tiniest of everyday events.

Here’s to finding your true places and natural habitats,

Candy

9 Comments

Candice Gaukel Andrews on October 18, 2013 at 3:56 pm

Carter & Olivia,
The butterfly farmer’s name is John Wahl. You might try contacting the Bronx Zoo, as it’s mentioned in the video that John supplies butterflies to that zoo. Or, t
hese might be of interest to you:
https://www.youtube.com/watch?v=QhyyPPPgL_w
https://mentalfloss.com/article/51464/inside-butterfly-farm
https://www.facebook.com/john.wahl.33
Thanks for the comment.
—C.G.A.

Carter & Olivia Ries on October 18, 2013 at 12:40 pm

Great stuff. How do we get in contact with the guy in AL with the Butterfly Farm?
Thanks for sahring

mo norrington on October 10, 2013 at 9:31 am

Great little educational film. Thanks very much indeed for sharing it.

Nicole Wexler on October 10, 2013 at 9:30 am

Wow, really beautiful and ingenious!

Susan Sharma on October 10, 2013 at 9:29 am

Thanks for a most revealing post! We have so much to learn from butterflies and moths.

Timothy Kerin on October 10, 2013 at 9:29 am

The cocoon looks like an elegant onion bag. I like the one-way escape hatch. The open structure conserves materials while as the commentary suggests, keeps rainwater from collecting and drowning the the pupa.
Although the apparently delicate structure and large openings would seem to leave the pupa at risk for predation, the video creators didn’t go into how tough the cocoon fiber was, what the moth’s natural predators are or defensive mechanisms (such as bad taste or toxicity) which the pupa might benefit from. It would be interesting to know if the pupae are always found below the canopy as was the one in the video. This would subject them to some predators but keep them away from others.
How about the single fuzzy string that suspends the cocoon? Assuming an ant was interested in eating the pupa, is there anything about the string that makes it difficult for an ant or other terrestrial insect to traverse, such as a microscopic stickiness? Just wondering…

Steven Dammer on October 9, 2013 at 5:11 pm

That’s a really neat adaptation, although I am curious as to how it protects the pupa from other environmental factors or predators. I agree with what he said in the video, it really does seem counterintuitive to the survival of the pupa.