Phylogeny of the shambling flannel

[bnewman]

Just now, fiddledragon and I were snuggling and she expressed a desire for a living flannel. We considered the morphology such an unusual lifeform would have to have. It consists almost entirely of furred epidermis. It should have rudimentary musculature in order to shiver to generate heat, and to power its distributed circulatory system. With its high surface/volume ratio, it can absorb oxygen through its skin — with a simple metabolism, it can also drink (a nectar- or milk-like liquid food) and excrete (chiefly water vapor and carbon dioxide) through its skin. It is thus pretty much homogenous in structure, with no centralized organs at all.

How could such a creature live in the wild? Since it's basically a furry animal without the animal part, it's probably a symbiote, providing furriness to a non-furry host in exchange for the host's nectar-like secretions. Wouldn't it be simpler for the host to just evolve it's own fur, though? How could such an improbable arrangement come to be?

Our just-so story begins with the humble nectarpatch, a parasitic fungus that attacks tree roots. The nectarpatch forms a hard crust on the surface of its host, and produces spores on microscopic filaments on the surface of this crust. To attract ants to spread these spores, it also exudes a sweet nectar over some of its surface.

The patch flatterpillar competes with the ants for this nectar. Although descended from something like a velvet worm, the flatterpillar is exquisitely specialized — in its adult form it is sessile, its ventral surface is covered with mouth-like pores to absorb nectar, and its dorsal surface closely mimics the crusty appearance of dead nectarpatch. Flatterpillars are hermaphroditic, exchanging sperm packets while still motile and storing them until the time comes to lay eggs as a sessile adult. The eggs are produced on the flatterpillar's ventral surface and hatch underneath. The offspring then wriggle their way out.

The anthunter is an insectivorous, amphibian-like creature which specializes in eating the ants which patronize the nectarpatch. Having the moist, permeable skin of an amphibian, of course, it is vulnerable to the ants' stings. The anthunter has evolved a pheromone which mimics the scent of nectarpatch nectar, which it uses to lure and confuse the ants on which it preys. Of course, this also has the effect of luring and confusing flatterpillars.

Fascinating, I know, but what of the symbiote? As the ants evolved to be more discriminating, the anthunter's luring secretions evolved to be closer and closer to real nectarpatch nectar — right down to the nutritional content. At this point it became possible for a flatterpillar to survive by drinking it. The anthunter's nectar glands were primarily on its belly, but a fairly common mutation put them on its back as well. If a flatterpillar settled on such an anthunter, it would have a reliable food source and the protection of mobility against predators that might steal its eggs. In return, the tough skin of the flatterpillar would protect the anthunter from stings.

Some flatterpillars evolved to live solely as an anthunter's protective coat. At first they had a more scaly, reptile-like skin which, in addition to protecting the anthunter from stings, also protected it from drying out. This allowed the anthunters to spread to other habitats, far from the jungles where nectarpatch is found, and eventually to colder habitats, where the symbiotes (not the anthunters!) switched from scales to fur, just as the ancestors of the first mammals did.

The modern, domestic shambling flannel has been genetically modified from this furry symbiote stock. It is much larger, of course, more resilient, and furry on both sides, with mouth pores scattered over its surface between the hairs. It lives on a liquid food formulated to resemble the anthunter's secretions. Certified genetically and biologically safe by the Galactic Federation, a shambling flannel makes an attractive, lovable, and functional pet.

Comments

[q10.livejournal.com]

sounds like you've got it about right.

[jere7my.livejournal.com]

A lacigolomyte!

(You won't have any idea what I'm talking about, but maybe someone reading this will.)

[wayman.livejournal.com]

And what a menace those were!

[nightengalesknd.livejournal.com]

I wonder if flannel would like to eat dryer lint.

[orawnzva.livejournal.com]

Dryer lint is mostly cellulose (from cotton) and keratin (from animal fiber), and you need a pretty serious digestive system to break it down. There isn't really room in the flannel to fit that much metabolic machinery. I think it's more likely that the flannel will like to drink smoothies.

[q10.livejournal.com]

is cellulose abstractly hard to digest, or is it just that the animal lineages we got issued are all bad at it, and so have to implement complex Rube Goldberg solutions. there are bacteria and protists (such as those working as symbiotes in termites, cows, and other macroscopic cellulose-eating animals) that seem to be okay at it - maybe the reengineered shambling flannel could learn to use some of their enzymes.

[orawnzva.livejournal.com]

Since the shambling flannel has only pores, and not a mouth per se, the real problem is that most cellulose is in the form of solid particles bigger than a few microns across, and thus cannot be physically ingested by the flannel.

[q10.livejournal.com]

well, it should have mouths - otherwise feeding it will get its fur all messy.

clearly you just missed the part of the story where the anthunter's upper-body nextar glands gradually concentrated into particular reasons and became more specialized feeding glands, while the symbiote's feeding pores became mouths that attached to them (part of this story is a lot like the probably evolutionary history of mammary glands in modern mammals) this was adaptive because it reduced wasted nectar at some stage in the development, and since juvenile flatterpillars presumably had mouths, it wasn't like the symbiote was having to figure out an entirely new piece of feeding machinery.

the wild symbiote identified feeding glands by a pheromone combination which it cannot distinguish from star anise, so grinding a little star anise into your drier lint will make the flannel precieve it as food. care must be taken to wash ones hands after handling star anise in the kitchen, however, unless one doesn't mind having them licked clean by the flannel.

[orawnzva.livejournal.com]

Actually, that adaptation was considered in an earlier draft.

The problem with lint is that, even if it has mouths, it won't have a stomach — the mouths will just lead to shallow digestive pores — so there's no way for it to eat solid food.

[boroparkpyro.livejournal.com]

i'm sorry, it sounds great except for the term 'mouth pores' :-P

[spin0za1.livejournal.com]

Proof that God exists and therefore God vanishes in a puff of logic. QED.

[wayman.livejournal.com]

This sounds a lot, in the end, like the cat blankets in the Miles Vorkosigan world....