The whitecap’s skin glows with a golden tan of cultured xanthophylls. Joel’s smile grows a little more brittle. He’s heard all about the benefits, of course. UV protection, higher blood oxygen, more energy — they say it even cuts down on your food requirements, not that any of these people have to worry about grocery money. Still, it’s too bloody freakish for Joel’s tastes. Implants should be made out of meat, or at least plastic. If people were meant to photosynthesize they’d have leaves.
I wrote that back in the late nineties. I didn’t invent it. I wasn’t even the first SF writer to exploit the idea, not by a long shot. Way back in the seventies Poul Anderson’s Fire Time described aliens with photosynthetic manes — (They nibbled on them sometimes, if I’m remembering correctly. Kind of an autophagous salad bar) — and out in the real world corals and tridacnas (tridacnae?) figured out the whole symbiotic-algae thing a few million years before Starfish came out. And yet, those guys aren’t really photosynthetic; they just loan out their flesh to things that are, skim a little growth energy in lieu of rent. Some nudibranchs eat the algae outright, incorporating the still-functional chloroplasts into their tissues — but even those guys are just living off someone else’s body parts, not growing their own. Except for science-fictional creations like my filthy-rich retirees in Starfish, anyone looking for a truly photosynthetic animal was SOL.
Until now. Until these nifty little creatures showed up in Nature last week.
Okay, maybe not exactly photosynthetic. It has yet to be definitively established that these little critters suck in CO2 and exhale oxygen, so technically we could be talking about a different process. But aphids do carry the genes to make carotenoids, a photosynthetic pigment common in various algae. Valmallette et al did observe the pigment itself, distributed in a layer just below the cuticle (just about where you’d want to be if you were a solar battery, for instance). And they found that aphids kept in lit environs had higher rates of ATP production than those kept in the dark.
Valmallette et al conclude that these findings “argue for a role of chromophores as part of an archaic photosynthetic mechanism in insects”; they drop seductive hints about “an archaic photosynthetic system consisting of photo-emitted electrons that are in fine funnelled into the mitochondrial reducing power in order to synthesize ATP molecules.”
So, not symbionts. Not devoured body parts. Photosynthetic animals. How cool is that?
It’s cool enough that Valmallette et al put the word “amazingly” into the official abstract, which breaks the cardinal rule of Thall Shalt Not Inject Emotion Into Science. In this case, though, Nature apparently thought the cause was more than sufficient.
It’s unlikely that aphids evolved these genes independently. More likely the traits were acquired via lateral transfer, probably from blue-green algae. Which segues nicely into another item involving those same elements: namely, the gengineering of blue-green algae for the production of biogasoline. Apparently1 the latest issue of BioScience contains a cautionary paper on the subject by Allison Snow & Val Smith, warning against unforeseen consequences — specifically, the possibility that “transgenes … could be transferred to other species in a way that could upset a fragile ecosystem”.
As chance would have it, I recently wrote a story on this very topic for MIT Technology Review. You may remember an excerpt (to which I’m not linking because it was a rough draft, and has since been improved), which describes exactly the kind of unforeseen consequences that Snow & Smith warn us about. (Well, maybe not exactly, but then again that’s the whole thing about unforeseen consequences.) (Late-breaking update — having since seen a copy of the paper itself, let me quote a line from the abstract: “Cyanobacteria are especially difficult to evaluate because of the chance of horizontal gene transfer with unrelated microbes.” So, at least semi-exactly.) Immediate consequences, though, give rise to longer-term ones— and as Frederick Pohl famously remarked, it’s not enough to predict the automobile. Science fiction’s job is to predict the traffic jam that comes after. So I’m going to sing you out with another fiblet, in which said traffic jam is caused by a goat in the road:
…the Polish alcohol-industrial complex had, by all accounts, experienced an unexpected renaissance of late. It was impossible to regulate. The EU had tried, with their ever-widening definitions of “toxic waste”. Exorbitant licensing fees made it all but impossible to purchase the product even in the restaurants and hotels of Poland itself— and yet it persisted, wound inextricably through the very DNA of the culture. Meaderies plied a hundred types of hooch on rickety tables in town squares; unmarked crates crossed national boundaries in search of more-forgiving environmental standards; homemade stills bubbled and dripped in every basement. Alcohol even played a prominent role in Polish justice; a traditional form of capital punishment back in Medieval times had involved forcing wine down the condemned’s throat through a tube until his guts exploded. (Some whispered that the practice persisted even now, in the remote woodlands of Lubelskie.)
Over the past couple of years the win and the wódka kawa had been making inroads into North America, and its devastating effects were showing up in the most graphic PSAs the Bureau could muster. It hooked those you’d least expect, they said: real family-values types who’d never touch a chemical that hadn’t come from a pharmacy or a tobacconist. Then one day you’d find their feet, still clad in socks and shoes like a couple of smoldering galoshes on the living room carpet. Maybe a bit of carbonized tibia poking through those cauterized stumps. After the funeral you’d go downstairs to pack up their tools for Goodwill and there you’d find it, back behind the water heater where no one would ever think to look: the box with the bottles inside, still half full of that mysterious pink liquid, viscous as machine oil. The labels with the funny accents over the Cs and the strange little slashes through the Ls and all those words ending in ski. And you would curse the vile Poles and their vile killer moonshine, and you would rage at the injustice of bad things happening to good people, and words like plasmid and lateral transfer would never even cross your mind…
1I will have to take this on faith, however, since BioScience is behind a paywall and it’ll be a while before I dig out a new tunnel through such things.