Human embryos go through some crazy changes too. Parts grow and are reabsorbed (tails). Many animals also shed hard exoskeletons regularly (lobsters, spiders). That involves softening up the inner animal. Perhaps that was a part-way step towards full metomorphosis.

Another interesting perspective is to look at it not as a more elaborate form of exoskeleton shedding, but as hatching from a very sophisticated egg.

Or as similar to a two-generation-cycle parasite that alternates between a host-A form creating eggs that grow into a host-B form (creating eggs that grow into a host-A form, etc.)

The pupa internally "gestates" the adult as a parthenogenetic clone-child; the adult being gestated, absorbs the pupal parent's entire body for nutrients — and, crucially, the pupal parent's body allows this absorption of its entire body, producing no immune response to it, because they have the same DNA. As with a cyclic parasite, you get two different complete lifecycles, that are each born, live, and die from the same genetic program, given a different epigenetic kickstart, in a back-and-forth cycle.

This sounds strangely similar to the code for the Morris worm.

I think the hypothesis is that it started as a delay in the internal development of wings. This split the creatures life cycle into a pre-winged feeding stage and a post-winged adult breeding stage.

The possession of wings in the later stage created a very different environmental situation, so the selective pressures on the winged stage are very different from those in the pre winged stage. These cause a split in the evolutionary environment of pre and post winged stages, causing selection for further divergent trait acquisition in the transitional stage during wing development.

Not an entomologist though, so if anyone has a better understanding I’d be grateful.

Frogs go through this process too though, and they don't have wings.

Frogs are strange too, but not as odd as insects at least to me. Frogs almost seem to just pause growth and then resume it. Definitely interesting as well though.

> pause growth and then resume it

Which shouldn’t feel so alien to us because human childhoods are a period of much slower growth than you see in other animals. Not a pause but still. IIRC it’s speculated that slowed growth is to give time for the brain to mature and to learn but either way it’s interesting to think about. If we grew the way dogs and cows to we’d be fully grown by around 10 years old.

You are right, and I am hard pressed to think of anything scarier than a pack 10 year olds with the strength of a man. Society may have taken an interesting direction.

Sure, the reasons why some creatures evolved this sort of behaviour could be different to others. I was specifically talking about Endopterygota.

Not entirely - they change shape certainly, but don't encapsulate and rework almost their entire organ system to do so. Insect metamorphosis is far more drastic.

Frogs seem to have a delayed Ontogeny, too, but the restructuring is much less drastic than insects.

Vertebrates go through several stages in their development while in the egg (or placental sack, which stands in for the egg). The develop a head, spine, and tail initially. Then they add front limbs and finally rear limbs. Frogs hatch from their eggs prior to the limb development stage and retain that neotenous legless form while tadpoles. They are essentially hatched as embryos and don’t assume their adult form until later.

It also prevents adult insects from competing with juveniles.

Someday, I predict humans will be able to undergo a similar process. Our main obstacle is building a suitable cocoon structure that could hold a human for the duration of the metamorphosis. Essentially what we do is trigger a process that can rembryonize the body and break down the excess material into base elements. This stew of embryo and nutrients then goes through a process of regrowth over the course of 9 months until the human has become a newborn baby again, with some core memories retained. Once born, the baby learns to walk and talk all over again until they are as functional as before the metamorphosis.

The obvious advantage of this process is you can regenerate a body if your current one is no longer suitable, due to disease, degeneration, or even dysphoria.

If reincarnation is real, isn't that already happening? Granted, it is not the same exact base material that gets rebuilt in a baby, but in a way the dead body gets decomposed, eaten by other animal and join the soil through feces or get cremated and join the soil/water. Then after sometime, someone gets pregnant gets nutrient form the soil (plants, fruits, grass fed beef...) and a baby is built. Obviously some of the individual base parts will go to other creatures too.

We only miss the memory, that which makes us individual human beings. I wonder where the hell does it go. That's is marvelous to me. Where does the memory go?

If memories are just a side effect of where certain chemicals flow along pathways, then along the lines of your comment...

A river is like a memory: water generally flows the same way down them, some days stronger some days drier, and the more they are used, the more they shift their course.

Memory is just a word for the human experience of localized state. There is a universal state that we experience a small piece of as we live. Though our experience of it ceases when we die, the state of the universe continues its natural course, with no loss of continuity, just a phase shift.

The experience of human life is like a river. At first we are small mountain trickles, barely aware of our existence. As we make our way through the middle of our lives, we are self-important rivers, providing an ecosystem to those around us, sometimes with others flowing their experience into ours, and sometimes as we give our experience to others; some amount evaporating to who knows where and some amount being replenished by rains, growing ever larger.

Towards the end, we either become stuck in lakes, or we are like large idle bays, full of experience, most of us moving now with less fundamental "purpose." Lake or bay, eventually we disperse back to the ocean of existence.

Where does a stack of stones go after it is toppled?

Maybe in the old days. These days you'd just reincarnate as decomposition bacteria and then live out your life in a pool of formaldehyde and human jerky chunks inside a sealed casket.

There are those cool liquefaction burial places though that will dissolve you in a strong acid (or base?). Your family is left with some you juice that they can flush down the toilet (or drink in a cocktail, I suppose).

Maybe the Tibetans and their sky burials with vultures eating your fresh meat is the way to go.

Aquamation. It's basically like when murder victims get dissolved in a bathtub full of lye, except they charge you a ton to do it, and market it as a gentler alternative to cremation, because it uses less heat.

This idea is a major plot point in one of my favorite webcomics: https://www.genocideman.com/?p=483

To me this reads as a really complicated form of physician assisted suicide. I also think the marketability of this would be complicated, as most adult people would want to start over in their teens or twenties, not as a baby.

Starting as a baby gives you a better chance at building a foundation for the kind of lifestyle you want when you reach your teens or twenties. Those baby years will go by quickly anyway.

It isn’t really suicide because your consciousness isn’t extinguished, you just end up unconscious for a bit while you restructure.

Who is going to raise a baby with the mind of an adult?

Family? Are we so broken that it doesn't pop out as an obvious choice? In China (lived there 10 years) I feel like many would accept this without even a moment's hesitation.

No, like putting that aside, because I assume that it’ll exist. I’m thinking more along the lines of, how do you satisfy the emotional needs of an adult who is trapped in a body that is not responsive to them? If I behaved like I do as an adult to my parents and teachers but I was a child I’d spend my entire youth in the timeout corner.

You'd have to pray your caregivers give you food that you actually like before you get teeth and the ability to walk.

So the scenario plays out: you get too old to have fun, so you metamorphosize back into a baby, which your now-adult children have to take care of. This is just as labor-intensive as care for the elderly you would have been, but now they have to go through the psychological horrors of knowing their mother/father is now a child in their care, adding to their load of possibly already trying to raise a family of their own?

Well this would be included in your payment for the service, a day care type home for regenerated humans. Maybe covered by insurance even.

Advertisers? Sponsoring baby content makers, baby athletes, baby celebrities... babies with six packs wearing designer diapers, riding their hipster e-strollers. Shit's dystopian, man.

Paul Atreides and the Fremen.

Porn companies.

If you start as a baby your body is too small and weak to get anything on your own, so the foundation of your life is actually built by the people taking care of you. How could you customize being helpless to suit a later presumed lifestyle? I also struggle to see how all the content stored in an adult brain could be transferred to a smaller-sized baby brain, when the brain grows as your body matures.

Or a horrifically fascinating take on religious belief in reincarnation.

Interesting idea, but I wonder how DNA error correction is going to function over artificially extended lifespans

Reminds me of Bruce sterling’s holy fire a bit

In a sense organizing tissues is the thing multicellular life does.