Phoebis sennae metamorphosis video produced by timelapse videographer extraordinaire JCMegabyte.
In a dream last night, I sprinkled water on a dried out, old mantis ootheca which I had given up as spent or dead. Miraculously, nymphs began rapelling miniature but almost fully-formed from the papery husk.
The butterfly expert V. Nabokov surmised that the monstrous unclean animal of Kafka’s imagination was most probably a very large beetle, and certainly not a cockroach as commonly assumed. I am inclined to agree with him not only on the morphological grounds from which he argues but also for the fact that that cockroaches like mantids (which are essentially toned, insecticidal roaches) and bugs and grasshoppers and sucking lice are hemimetabolous. They do not metamorphose. Or as the convential parlance has it their metamorphosis is “incomplete.”
Though form does change from instar to instar to imago in the hemimetabolous orders, these changes are more or less subtle – an increase in body size a subtle change in shape or color the growth of wings. Dragonflies are hemimetabolous desipite their dramatic transformation from killer submarine to muderous biplane – the shadow of the naiad can be seen in imago with some imagination.
True (“complete”) metamorphosis is a trick reserved for the endopterygotes – butterflies and bees and beetles, flies and fleas and ants and ant lions &c. Each of these groups begins life as a wormy larva hardens into a mummylike pupa in which the body tissues literally digest themselves and build an entirely new, wonderful thing not at all like the melted maggot or caterpillar from which it precipitated.
It is much, much easier to imagine the maggoty Gregor metamorphosing into a beetle than a cockroach.
All of which is a wholly unnecessary preamble to THE MOST, most bizarre scientific papers I have read all year: weirder than hermit eurypterid hand puppets, stranger than penguin poop from space, more fantastic than plastic barnacle penes, and more incredible, even, than psychic protists.
I’m speaking of course of Donald Williamson’s mind-bending new paper in PNAS: ” Caterpillars evolved from onychophorans by hybridogenesis. ” (DOI: 10.1073/pnas.0908357106).
Without, it seems, a single piece of empirical data to support his claim, Williamson posits that the larval stages of holometabolous insects (and other animals which undergo dramatic post-larval transformations) evolved via “Larval Transfer” when insects mated with velvet worms! Butterflies (and beetles, and flies &c.) are, in this view sort of sequential transphyletic chimera. This is something like, well a human mating with a cockroach which then gives birth to a human that then eventually metamorphoses into a cockroach. Or something.
While this is an, ahem, iconoclastic proposition to say the least, and it is fairly astonishing that it appears in one of the most prestigious general science journals, Williamson at least proposes a “research program” to test his hypothesis. Here is one experiment he proposes:
As an initial trial, it should be possible to attach an onychophoran spermatophore to the genital pore of a female cockroach and see if fertilized eggs are laid (page 4 from Williamson 2009)
This is like some awesome Dr. Moreau style shite. The entire paper is sort of like a Lynch film: wonderful and horrifying and you’re not sure if it’s some kind of put on or there is some kind of insane genius at work.
The back story; and some choice quotes expressing the astonishment with which this paper has been received by the uh, “mainstream” scientific community is covered in this Scientific American article.
But. Dude. Seriously?