Naturespeak A naturalist's view of the world

August 27, 2009

Not Just Hanging Around

Filed under: Uncategorized — wykes @ 9:19 pm

I was prompted to return to the subject of Viceroys because of a beautiful green example I found earlier in the week. Viceroy butterflies, while always orange and black as adults, come in green or brown models as larvae. The brown versions are great poop mimics and these are the ones I’ve presented before. They are easy to spot but protected by their unappetizing crappy features. The green ones, on the other hand, are hard to spot against the leafy green of their chosen food plant (see above).  In this case, the chosen fare was a shrub willow – a typical food for these royal larvae who also go for populars, aspens, and cottonwoods.

As you can see, or not, his outline is purposely unpredictable and his wardrobe completely disorienting.  It’s hard to tell which end is which (although you can see the head at the lower end in this shot). In both views, the ‘piller is contorted into a defensive pose which presents a pair of spiny clubs as a deterrent. I was not deterred, so I took the creature in for some TLC and closer observation.

Less than four days later, this bumpy green eating machine ended his consumption days and began to prepare for bigger things. A horizontal leaf was selected for weaving a button of silk and, after grabbing this pad with his hindermost legs, he released his hold and suspended himself upsidedown (see below). This “J” pose indicated that the creature was about to pupate. You’ll note that all the green pigment has been re-absorbed and the thing took on a pale brown look. Big changes were beginning to occur at this point as the viceroy begins to literally digest itself.

Internally, the leg muscles, digestive tract, and mandibles are beginning to dissolve and the inner layer of skin toughens into a new textured surface.  There is no turning back at this stage. A day later the old skin was cast off and the form of a newly shaped creature was unveiled (see below). This chrysalis stage little resembles the caterpillar it emerged from because internally it is no longer a caterpillar – it is a butterfly in a juice bag. All the larval organs are rendered into goo (a process called histolysis) and the cells are being transformed into new adult organs.

Probably the best way to think about what is going on is to imagine a pile of legos. The original pile of building blocks – like cells- were used to build a Viceroy caterpillar. These same blocks are now being disassembled and re-arranged inside a toy box in order to create an adult with wings, antennae, and a sex drive. Instead of hands doing this job, however, tiny spots on the larvae’s skin called histoblasts or imaginal buds, are directing the re-construction effort.  I suppose you could call these creative moles!

The chrysalis may look like a dollop of drippy bird doo, but close examination reveals the outline of the wings, head, antennae, and legs of the future adult (especially in this frontal view). Breathing pores, called spiracles are evident on the sides of the abdomen. Viceroys are able to have three generations per year. This chrysalis, the result of the second generation,  will hatch out as an adult in a week or so. This winged version will mate, lay eggs (if a female, of course) and die. The tiny caterpillars that emerge as the third generation will not eat, but will instead roll themselves up in a leaf tunnel and wait out the winter. Next spring they will resume eating, growing and pupating.

For now we are left contemplating this ungainly looking chrysalis. The thing will wiggle a bit if touched, but for the most part it will hang like a still-life. The innards of this still-life are anything but still – the boiling stuff of creation is contained within.

5 Comments »

  1. Those are the coolest photos! Up to now I’ve seen caterpillars and chrysalises and butterflies, but not the inbetween stage from caterpillar to chrysalis. Fascinating!

    Comment by Monica the Garden Faerie — August 28, 2009 @ 10:25 am

  2. On the one hand, that is totally revolting (self-digestion), but on the other hand it is totally cool! I wonder if the process of total body realignment is painful, and if that is the reason to pupate. Hm. Great post!

    Comment by Ellen — August 28, 2009 @ 3:38 pm

  3. Often, eating allergic articles taking an overdose of food also causes swelling. Some people are allergic to dairy products like milk, etc. This condition is also known as lactose intolerance. People with lactose intolerance also developed swelling in his abdomen. Women who are experiencing their menstrual cycle or who has the problem of ovarian cysts are also likely to suffer from swelling.

    Comment by Bart Ethen — May 3, 2010 @ 1:54 am

  4. i also have lactose intolerance that is why i always avoid dairy products..’`

    Comment by Freya Harris — May 20, 2010 @ 10:32 pm

  5. I have a bit of lactose intolerance and consuming too much milk really gives me an upset stomach. .*.,’

    Yours truly http://healthmedicinelab.com/warts-on-feet/

    Comment by Vicenta Mondoux — August 9, 2012 @ 6:09 am

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