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Oh no! It didn't make its harness!

We figure that by bringing eggs and cats indoors we are allowing many of them to survive that otherwise wouldn't have. Is this a good idea? Mebbe, mebbe not.

When you've seen quite a few of these critters grow and develop, you start to see some quirky behavior as the ones with marginal coordination that keep falling off branches and have to be rescued, the ones that get the timing wrong and start pupating before they have poopated (emptied their guts), the ones who do a lousy silk spot-weld of tail to branch and end up hanging only by their harness-thingie, and the ones that for some reason can't quite seem to get the hang of making the harness and instead end up dangling only by their silk-attached tails.

Both the ones below are in the latter category...or at this point, pupagory.

Although it probably would have been perfectly OK to leave them dangling, I decided to move them to what was surely a more comfortable position and location---lying on a paper towel. The tail attachment silk of the J'd-up caterpillars was gently pried loose from the surface they were attached to and the cats were placed on the paper towel.

Both shed their skins on schedule while lying on the paper towel; in fact the one on the right (above) had shed only an hour or so before the photo was taken...its wad of shed skin is directly adjacent.

So, do they need to be hanging by a proper harness-thingie to pupate properly, and then to hatch into gossamer flying machines? Heck no...just about anywhere and any position will do.

Don't forget: One thing you should be sure to do is to provide some means for the newly-emerged butterfly to climb up and away from the paper towel or other surface.

This is because a newly hatched butterfly needs to cling to an object that is oriented such that gravity pulls the unfurling wings away from its body rather than toward it.

Given a choice, the new butterfly will usually perch on the underside of a horizontal or upward-angled twig. So prop up a few twigs or straws near the pupas with enough space beneath them for a pair of pumped-up butterfly wings.

We think that harness-non-makers (and other serious behavioral outliers) are probably the ones that Mother Nature had been willing to sacrifice in the interest of Better Characteristics Through Random Gene Shuffling and had they been outdoors most would have been recycled early on. So we are relieving our eggs/cats/pupas of various selective pressures, and we can only hope that we are not muddying the local gene pool too much.

When things go really wrong: There are, of course, far more horrific scenarios than that described above--sometimes the harness thread slices into the delicate new pupa while the pupa is wriggling its skin off, and damages the pupa, an example of which is shown below:

image of pupa sliced open by its harness

If the pupa survives, the butterfly that emerges (if it is still alive and can emerge) will have various deformed parts, perhaps severe enough that it cannot ever hope to fly.

The above pupa, in addition to having the slice, was leaking fluid and the prognosis looked poor. So after about 2 seconds of careful deliberation it was decided to place the critter in the freezer to hasten the inevitable demise. Actually, the above pic was taken after the pupa had been frozen. The reason it looks glisteny-wet is that it is --- from condensation forming on the surface of a very cold pupa.


Here's another oddity--a black something-or-other on a pupa:

black strip on pupa

Looking more closely, this appears to be a remnant section of skin --part of a black stripe--that was left behind during the final molt:

black stripe material on pupa

It's still under the silk harness thread and disappears beneath a fold on the surface of the pupa. Below, spines are visible in the transparent section, and there is what looks like another remnant of skin barely visible to the right, and beneath the same fold.

Being caught under the fold may explain why the bit of skin was left behind.

black material on pupa

It'll be interesting to see what emerges from this pupa.

Update: what emerged was a normal healthy butterfly. The empty pupa is shown below:

Image of empty pupa with remnant of black stripe remaining