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Counting Chrysalis

Tuesday, January 28, 2014 - 01:00 PM

There are more shapes to a chrysalis than I could ever imagine. I know this because I stared at several hundred chrysalides (that's the fancy plural form of chrysalis) for two hours -- waiting for one, just one, winged insect to emerge.

As part of our Black Box story, "Goo and You," I found myself looking at chrysalides down in Gainesville, at the McGuire Center for Lepidoptera & Biodiversity. They have the Rearing Lab, a room that's really more about its wall:

In this wall, a plexiglass space with 16 shelves (four columns of four shelves), hang hundreds upon hundreds of butterfly pupae gathered from all around the world, from Malaysia to Costa Rica; at any time, representatives from up to 90 tropical butterfly species hang in this hollow space, waiting to emerge from their chitin shells. And visitors, like myself, wait to see the magic happen.

Using a hot glue gun, chrysalides are attached upside down to a piece of paper, which is marked at the very least with the species name, and then hung from beneath the shelves. Behind the wall, you can see the room where the workers remove the newly emerged butterflies from the plexiglass chrysalis case, and then transport them to the nearby butterfly rainforest.

Standing in front of hundreds of mostly still* chrysalides, waiting for something I should have seen far long ago but realized I hadn't, there's nothing much to do but stare, scrutinizing each of nature's various dressing boxes. There were jellybeans, flower buds, twigs, bark, and shrimp...cones, snail shells, and sea shells...white, green, black, malachite. Here's a chrysalis, disguised as a leaf for protection:

The darker the chrysalis, the closer the butterfly is to emerging. So in the leaves above, the light brown casings contain a butterfly about to emerge, if one hasn't popped out yet. The change in color comes from the butterfly pulling away from the outer layer of the chrysalis as it gets ready to push out. Next are the snail shells:

The white ones are empty, butterflyless...and then, here are beauties that look like tight, glistening, green pasta shells:

You'll notice two pools beneath each of the newly emerged butterflies (sadly, I missed their birth!) -- that's meconium, also called the pupal liquid. It's dead cells from the gut, left over from metamorphosis, expelled from the butterfly after emergence (for those parents out there, you'll also remember that your newborn has their own version of meconium). A reddish liquid, it's often mistaken for blood, but isn't.

And then, finally, we get to my favorite chrysalis, the gold:

 

These chrysalides look like they are jewelry; not even butterflies, but ants, pounded out of metal foil. But they aren't.

Made out of the same chitin as other chrysalides, scientists suspect that somehow, the cells are layered in such a way that they reflect light, appearing metallic. Here's a butterfly whose pupa is merely decorated in gold dots, nature's accessories:

In fact, this gold coloring is so common in butterfly pupa, that is how it earned its name: chrysalis comes from the Greek word for gold, chrysós

As for what purpose such all-over metallic coloring or dots perform? Science isn't really sure. Perhaps camouflage -- maybe the gold looks like dew drops; perhaps a light filter, preventing harmful wavelengths from penetrating the shell. Recently, a scientist using a micro-scanning technology saw that in monarchs, what is called the "gold crown" -- a circle of dots around the abdomen of the chrysalis -- are in fact openings that air passes through.

There's one other thing I didn't know about chrysalides, and you can see it here, if you follow the arrow:

That little tuft. You see it? Hanging off the dried pistachio-looking chrysalis in the corner? It's the shriveled-up skin of a caterpillar. See, it turns out, caterpillars don't crawl into the chrysalis...they molt into it. We all know about molting, right? As a caterpillar gets bigger and bigger, occasionally it sheds its outer layer of skin, and there's a new layer of caterpillar skin underneath that it grows into. Well, it turns out, caterpillars actually also grow the chrysalis beneath their wormy skin, so that one time, when they are big enough, they molt not into a bigger caterpillar, but into a chrysalis. The chrysalis that comes out from under the skin is soft and wet, but hardens over a few hours. So they don't crawl into the chrysalis, they morph into it, shaking off their old caterpillar skin. But, sometimes, that skin stays attached to the pupa by the skinniest of threads; it just hangs out, so you can see some semblance of the earlier creature that led to the chrysalis.

So. I know you're wondering: after two hours of waiting, almost missing my flight, did I see anything bust through these decorative homes? With ten minutes to spare...I can say that I did. I'd like to introduce you to our butterfly, popped from a chrysalis that appears like a decomposing stick; a piece of detritus. We like to call her Radiolab (she's the furthest one to the left, with that bit of light reflecting):

 

 

*Believe it or not, it's not uncommon for a chrysalis to wiggle. Here's one that blew me away with its aerobics:

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Comments [9]

Joel Heiland

You say that the watery liquid under the empty case after the butterfly has hatched is "leftover cells"; I wonder if this was a fluid used to pump air into the vanes of the wings to extend and unfold them. I have hatched Momarch butterfly's and found that after the wings are flat and dry they expel about 12 drops of a liquid from the back end of the abdomen. I have always wondered if this liquid is a hydraulic liquid used to pump air into the vains of the wings because just before the wings unfold the abdomen becomes enlarged or over extended. Would love to have you thoughts on this and would like to send my photos to show this as I saw it. Thank's Joel

Jul. 15 2014 03:41 PM
captbilly from California.

I must have been listening to a rebroadcast of this story (since the original air date seems to be from January) but I was appalled by how stupid it got at the end. Trying to draw conclusions, or even connections, between what happens when a chrysalis turns into a butterfly (or moth) and what happens to a human (or any other creature) when they die is without logic or merit of any sort. The fact that the creature that comes out of a chrysalis seems to have some memory of it's experiences prior to entering that stage is interesting, and completely explainable. That this transformation would illicit questions about what one might remember after death is so obviously nonsense that a child would understand.

The dialog in the part of the story I heard on the radio (the last few minutes) was about as meaningful or logical, or intelligent as what one might expect from a bunch of teenagers who smoked weed for the first time. You can do better.

May. 28 2014 04:17 PM
Dolly A from France

This article definitely would have been aided by some better photography, half the things your trying to show us are out of focus! More than slightly frustrating.

Feb. 20 2014 06:48 AM
Chris Ward from New York

Interesting segment on butterflies almost ruined by faux mystical spooky commentary. Get a grip and keep your Theology away from your Entomology.

Feb. 10 2014 07:47 AM
Caitlin Burkman from Ohio

Great story! As an undergrad I worked in an entomology lab that reared tobacco hornworm moths. Unlike butterflies, moths often pupate on the ground or in leaf litter, and their chrysalides are much less flashy. We placed the pupae into wood blocks with holes drilled in and they "incubated" for awhile. Then into the eclosion chamber for emergence! Watching them wiggle around was so funny, and seeing the process of egg to adult was fascinating.

Feb. 04 2014 11:49 AM
elizabeth burger from westminster, MD

How cool. I saw one of these labs for butterflies in Amsterdamn a few years ago...all hanging side by side, the Monarch, the leaf looing one and something else. I love reading about the inside story. I use milkweed pods and the inside seeds in my work as an artist. I will have them displayed at the Montpelier Art Center this summer in Laural, MD, clinging to the wall and pierced with palm fiber, looking like insects- hundreds of them. And also hanging ppods of milkseed encased in invisible hairnets strung with palm fiber again(from Brasil). Come and visit.
Thanks
Elizabeth

Jan. 29 2014 06:16 PM
Kilo Zamora from Salt Lake City

Hello,
I was intrigued by the section of the story where the lepidopterist used a shock and smell experiment of the chrysalis to see if it impacted the butterflies behavior. I am interested to know if the same experiment has been tried on a butterfly to see if it effects the caterpillar. In the social sciences their is a growing body of research on historical trauma. Trauma that has been transferred from generation to generation [search american indians and historical trauma or holocaust and intergenerational trauma]. Also, the main idea discussed in the podcast about why the butterfly responded negatively to the smell experiment was that parts of the caterpillars brain were still intact during the pupa stage. What about the role of RNA programming? If major trauma is induced at a formative stage would not the life form have automatic response to turn off certain RNA codes?

Jan. 29 2014 03:42 PM
Jamil from Dubai

Honestly one of the most interesting things I've read and heard about. After listening to the black box episode I could not stop thinking about butterflies. Also, I adore the comparison between the idea of struggling man rising as a beautiful soul and caterpillar working hard and crawling and finally "resurrecting" as a butterfly. Quiet awesome.

Jan. 28 2014 06:25 PM
Becca

I was upset at the moment in the show when the pupa is cut open, but feel conflicted in the interest of science, discovery and understanding. (Or really, maybe only the first person to ever cut open a pupa could be justified in using this as an excuse.)

"Sweet is the lore which Nature brings;
Our meddling intellect
Misshapes the beauteous forms of things--
We murder to dissect."

-Wordsworth "The Tables Turned"

Jan. 28 2014 04:12 PM

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