Friday Sprog Blogging: silkworm reports from the field.

We're going on three weeks since the first of the Free-Ride silkworms made a cocoon.


So far, there have been no signs of anyone trying to get out. So we'll have to wait a while yet before we witness the miracle of life (or of silkmoths bumping bug uglies, depending on your perspective).

In the meantime, we've heard reports from the field about other silkworms that came home from school.

In one household, while the child with primary responsibility for the silkworms was still trying to secure a supply of mulberry leaves, the silkworms were fed apple leaves. The silkworms did not die. However, a judgment was made (how, I'm not sure) that the silkworms were not getting as much thirst-quenching goodness out of the apple leaves, so they were offered water as well.

There are good ways and bad ways to offer a silkworm water.

One of the classrooms at school built little silkworm "houses" -- decorated paper boxes, really. A kid in that classroom decided to quench a silkworm's thirst by pouring some water into the silkworm house. The silkworm was OK, but the paper box was not. The preferred method to offer silkworms water, apparently, is to spritz some water on a leaf and let the silkworm at it.

We also heard a very sad report that a younger sibling in another household colored a silkworm with a marker, resulting in the death of the silkworm. The elder Free-Ride offspring hypothesizes that the marker ink must have covered the silkworm's breathing holes, suffocating it.

The Free-Ride silkworms were fed the canonical diet of mulberry leaves. We didn't offer water because we had been told that the mulberry leaves had enough moisture in them, and we didn't offer other leaves because we weren't sure if they would be toxic to the silkworms. Now, though, we kind of curious about whether the silk spun by the apple leaf-eating silkworms is detectably different from that spun by mulberry leaf-eating silkworms.

It might even be an interesting staring point for a science fair project.

Except for two things. First, the rules of the science fair specify that all projects that include animals must involve observation of animal behavior only, not (presumably) experimentation with the animals. Does changing the diet of a silkworm amount to experimentation? I'm inclined to think so.

Second, due to school budget cuts, there won't be a science fair next year.


When the silkmoths emerge, we'll tell you about it here.

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Has there been any hypothesizing about why some of the cocoons are noticeably paler than their lemony looking sibs?

We don't really know why some of the cocoons are white, some are golden, and some are a lighter yellow. It might be a genetic thing. Indeed, if we had a large enough population of each, we might segregate them so that the mating happens between former silkworms who made cocoons of the same color (then segregate the eggs, and the resulting silkworms, to see what happens to the next generation of cocoons). At this point, though, there are few enough white and light-yellow cocoons that I'm not 100% sure we'd end up with the male-female split we'd need for successful mating.

Chezjake beat me to it. I don't wear silk because of the traditional method of obtaining the fiber, but your expt causes me to wonder: is it possible to harvest hatched cocoons? If so, it would be interesting to know whether the color difference indicates any other differences in the fiber.