By Nicole Parizeau
A fresh and robust slime trail can trap a rolling dime.
On a crepuscular sidewalk, from a certain angle (you’ve seen this), a snail trail glows like pearl. This morning, in my path, running like a minuscule creek under a small brown moth, a slime trail lobs back the sunrise.
A land snail has two navigational imperatives: to stick and to advance. Pretty incompatible, as needs go…but metaphorically speaking the snail is exquisitely two-fisted, adapted to both stick and make headway. Using an evolutionary expedient roughly equivalent to sneezing through our feet, the snail secretes a thin film of mucus on which to crawl.
Gastro (stomach) + pod (foot). For every millimeter of locomotive progress, muscles in the snail’s foot ripple from back to front, each wave propelling the mothership forward. The slime secreted in the process is a snail’s private highway, laid down as he goes.
Fresh mucus is viscous and adhesive. (See your toddler for more on this exciting quality.) More than that, mucus has entrancing physical properties: It is a non-Newtonian fluid, meaning it changes viscosity according to the pressure it’s under.
Through complex transformations of state, as the foot presses down, the slime compresses, ruptures, and thins out. It gets slick. Atop this lubricant the snail glides forward like an egg on Teflon. As the snail moves on and its foot eases off, the slime—non-Newtonian—reverts to its original state. Gastropod alchemy; in the wake of its maker, the trail firms up.
This is the rhythm of the snail, to stick and move forward, stick and move forward,
stick and move forward, to navigate the world.
The slight moth at my feet in the sunrise is Inga concolorella, a common moth that has no common name. She has the mass of a postage stamp and the unremarkable sepia wash of many moths, finely pixilated to blend in with her habitat. Her antennae are spindly—nothing like a male’s feather dusters, which can snag a pheromone more subtle and distant than a drop of cologne on a passing train. Inga females have adapted to broadcast a siren call, not receive one.
I don’t know if this moth alit to rest, or fell to earth, or fled a predator only to flutter into this thin smear of goo. It doesn’t matter now. She’s encountered the slime trail of a snail or a slug and is struggling.
I don’t know if a moth can broadcast news of a disaster.
There is no blame in nature. Slime is the glory of the snail that passed by. He concocted it, laid it down, and slid along-top like a barge on ball bearings. In his wake unspooled a gummy, moribund macadam. Along came a moth. By the clock of natural traffic the snail is long gone, oblivious of his trail and inculpable.
I watch Inga struggle without interfering. Hung up like this, in a mouse-eat-moth world, she’s likely to become a meal. More than that; from the state of her, she’s beyond saving.
I watch her energy flag and her already ragged wings bust up in increments, and my heart busts up too.
Nicole Parizeau is former senior editor at Whole Earth Magazine and principal editor at University of California, Berkeley’s Lawrence Hall of Science. She has served as interpretive naturalist with California Department of Fish and Game, raptor rehabilitator with MacDonald Raptor Research Centre in Québec, and associate director of animal care at the Marine Mammal Center, north of San Francisco. Recent prose and poetry appears in Folio, Poecology, Emrys Journal, Written River, and other publications. http://www.nicoleparizeau.net/