3.10.2008

Other things, et cetera, and so on #1

On Moths, Soup, and Memory

A recent study appears to show that moths retain caterpillar memories. Please check out the article for details, but to sum up, the researchers trained some tobacco hornworm caterpillars to avoid a certain smell by shocking them, and even after metamorphosis, the resulting moths also avoid the smell.

Having been delinquent in maintaining my up-to-date knowledge of moth metamorphosis research, there were a couple of things that really jumped out at me from this article.
  1. Caterpillars can be trained? Upon a moment's thought, it seems obvious that just about any organism with any sort of somewhat sophisticated neural system would be able to develop a kind of sense memory, or learned response to stimuli. I just hadn't pondered the particular case of the caterpillar.
  2. On the face of it then, it doesn't seem totally alien that the resulting moth would retain some of the caterpillar-ian memory. It is the same organism, regardless of its form. That is, until I learned the following.
  3. During the pupa stage (in the cocoon), the metamorphosis apparently isn't just a rearranging of parts.

"The intriguing idea that a caterpillar's experiences can persist in the adult butterfly or moth captures the imagination, as it challenges a broadly-held view of metamorphosis -- that the larva essentially turns to soup and its components are entirely rebuilt as a butterfly," says senior author Martha Weiss, an associate professor of Biology at Georgetown University. (bold added)

Soup?! As I said, I haven't kept up with moth science, but I had never heard that metamorphosis was such a radical tear-down and rebuilding. I mean, what happens here? Do some enzymes get activated that liquify all the body parts into constituent proteins and genetic material? Or individual cells? Or groups of cells/proto-organs? How does the rebuilding take place? Some cellular structures must be controlling this process, but I can't reconcile a soup-theory with any other process I know about.

Can anyone out there shed some light on this Soup Theory? I've done some cursory searches to find out more advanced explanations of the metamorphosis of moths and butterflies, but I have yet to find anything satisfying. I'll keep looking and post what I find, but if anyone has any links to check out, please post them in the comments.

To me, this issue is crucial to understanding the caterpillar-to-moth memory trick. If the Soup Theory means that even the neurological system is dismantled or even dissolved and then rebuilt, retaining memory seems impossible. This leaves the question of whether some structures are retained (like the 'brain') and the rest of the 'soup' organizes around them.

I first heard this story this morning on NPR, and the researcher who was interviewed made an offhand joke at the end, saying in effect, "We may be getting closer understanding metamorphosis, but we still have no idea why moths crash into porch lights." This was rather annoying to hear, because a pretty good theory for this behavior has already been put forth.


Name That Religion

Here are some quotes from an article about intra-religious clashes in the middle east between hardcore members and more mainstream members over properly modest dress and other public actions.

Dr. H_ is a modern (religious) woman who dresses modestly, ... and observes the (tenets of the religion). One day driving home, she saw that someone had put up a sign in her neighborhood that read "Don't pass here unless you dress modestly."

"I find that offensive," she says. "I don't think that anybody should impose dress codes on the public."

When she tried to haul the sign down, some ultra-(religious people) pelted her and her car with rocks. Dr. H_, who asked that her full name not be used, went to the local police, but she says they did nothing.

...

That rock attack was hardly an isolated incident. People driving on the (holy day) have been bombarded with rocks. Earlier this year in B_, a young ... woman was sitting next a (national) soldier on a public bus when ... men assaulted both of them and forced the woman off the bus. Men and women, they said, should be segregated. Later, (a member of the same religion) who stood up to the zealots within his own community was himself brutally beaten. He said it was like a pogrom.

If I was reading this post, I'd think the quotes came from an article about Iran. That would be wrong. The story from NPR is about ultra-Orthodox Jews in Israel.

The parallels between ultra-orthodoxy in Judaism and Islam (and Christianity, too) are very striking.

I don't see any greater lesson here than that, however. It's not surprising in the least that religious zealots would do something like this, regardless of the religion. And though there may be some extra-crazies making things tough on the not-quite-as-crazies, either in Iran or Israel, at least the Jews aren't turning out anti-Western terrorists hell bent on our destruction.

But while we focus on the terrorist threat, and even though some are starting to come around to the view that we really are fighting militant Islam, it's important to remember that the essential nature of all religion -- subjugation of self to the supernatural, and denial of an individual's right to their own life -- is the defining characteristic that makes the pogroms possible.

1 comment:

Jenn Casey said...

Homer says: "Mmmm....caterpillar soup....aaagggh."

Never heard of the soup theory myself. I would be interested in learning more.

And yes, I assumed that the unnamed religion in your example was Islam. You're right--I've absolutely no doubt you'd be able to find Christians in this country who would do or have done the same thing.