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What happens to a caterpillar's brain and nervous system during its transformation to a butterfly? Does it remain? Is it completely replaced? What is the likelihood that a butterfly remembers its life as a caterpillar?
The article mentions that memories are maintained - I didn’t see a source, but here is an article about it: https://www.newscientist.com/article/dn13412-butterflies-rem...
Seems like you could test that via negative stimulus. Introduce a negative stimulus like a shock associated with something perceivable by both the caterpillar and butterfly. After conditioning the caterpillar, see if the butterfly shares the same aversion to the stimulus.
This has been tested! In moths at least:

> Manduca sexta caterpillars received an electrical shock associatively paired with a specific odor in order to create a conditioned odor aversion, and were assayed for learning in a Y choice apparatus as larvae and again as adult moths. We show that larvae learned to avoid the training odor, and that this aversion was still present in the adults.

https://journals.plos.org/plosone/article?id=10.1371/journal...

The caterpillar turns to mush. Its nervous system seamlessly morphs into a new one. Many neurons are retained, some are pruned, and some new ones are formed.

This is why certain memories can be retained and certain ones can't.

I remember being taught this as a child and iirc recent studies say it doesn’t mush.

EDIT:

"Textbooks will commonly talk about the insect dissolving into a kind of “soup”, but that’s not entirely accurate. Some organs stay intact. Others, like muscles, break down into clumps of cells that can be re-used, like a Lego sculpture decomposing into bricks. And some cells create imaginal discs—structures that produce adult body parts. There’s a pair for the antennae, a pair for the eyes, one for each leg and wing, and so on. So if the pupa contains a soup, it’s an organised broth full of chunky bits."

https://www.nationalgeographic.com/science/article/3-d-scans...

> No one’s ever seen this before

Except for (at least) the guy that discovered and presumably named it - André Blanchard?

The article is full of this kind of stuff.

Perhaps Wager meant no one had seen the juvenile form.

Blanchard had a holotype of the moth only. [1]

[1] https://archive.org/details/cbarchive_49606_anewspeciesinthe...

But how would he know that the caterpilar was that of the adult? Not saying it wasn't, but without observing its life-cycle, or DNA testing it would be impossible to say. You can't simply whack a bush and then say "nobody has seen this critter before".

Please note that this is a criticism of the journalism, which I think is crap, not the science.

It's mentioned though:

> Based on a series of taxonomic calculations, Wagner was convinced that the caterpillar was the juvenile form of an exceptionally rare moth known as Ursia furtiva.

Hypothetically, how could taxonomic calculations conceivably tell you that an unknown animal form belongs to a known species?

They can tell you that the form you're looking at is related to certain other known forms. That's it.

With additional knowledge about biogeography, species ranges, species sampling coverage / description rates, already proven adult-larvae identity and so forth, they can get you sufficiently in the ballpark to make a strong prediction that in popular reportage is forgiveably rendered as "sure".

Wagner is a career lepidopterist and an authority on caterpillars. He will be intimately familiar with caterpillars in the family Notodontidae (which contains the genus Ursia) and know their characteristic morphology and diversity. There are only two species known in the genus Ursia. The other one has a more southwesterly range and is not known to occur in Texas. Also, the caterpillars of species in closely related genera in the Notodontidae are well-surveyed. So, looking at a shrub in the range of Ursia furtiva and finding a caterpillar that fits the bill in terms of expected morphological characters, and being able to rule out its belonging to closely related genera, it's a reasonable leap of logic to attribute the larva to that particular species only previously known by its adult form. It's not "certain" at that point, but as a biologist who spends his life researching those taxa, and knowing well where the missing gaps are, it's the kind of hunch that is very often proved correct.

Do we agree that Blanchard saw the moth and the journalist is quoting someone looking at the caterpillar?
I tried to give an explanation further down this comment thread, if you're interested
how do you read it if you aren't cool?
The paywall is implemented in Javascript; the article loads fine with Javascript disabled.
Damn, that was the most fun article I've read in a long time!