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An algal scene

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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A golden pennate diatom and a green euglenid, Phacus sp., industriously photosynthesising before the slide dries out. Perhaps unexpectedly for its appearance, the diatom can actually move, by secreting mucus to glide on through the raphe (a slit), and often quickly enough to screw up your photography. Luckily, this one was paused at that moment. The colour comes from its plastid, of the "brown" algal category.

The euglenid's surface is covered by proteinaceous strips making up its pellicle -- in many species, they slide against each other and enable metaboly, a pattern of movement that makes the euglenid feel 'squishy'. This genus, on the other hand, lacks the sliding ability of its pellicle strips, and sits rigidly in one shape. Inside are a big clear doughnut-shaped starch globule, a red eyespot used for seeking light, and numerous green plastids that were once inherited through secondary endosymbiosis of a green alga. Only a single clade of euglenids is photosynthetic -- the rest have never seen a plastid as anything other than a food item.

(a wallpaper version can be found here, hopefully big enough to crop or shrink as necessary)

About Psi Wavefunction

I first encountered the wonders of the protist realm back in childhood, when a murky droplet of pond scum was revealed by the microscope to entail an alien world in its own right. It took another decade to discover there was a field and a community dedicated to these organisms, and I bade farewell to the study of more familiar big things. As a kid I was also fascinated by tales of exploration of the New World, as well as those of fantasy worlds. I was then sad that the age of surveying new landmasses on earth was over, and that human extraterrestrial adventures are unlikely to happen within our lifetimes. It seemed everything was discovered already. But that could hardly be further from the truth -- all that is necessary to begin one's own Age of Exploration is a new approach or perspective, and a healthy does of imagination. Since reality has conjured far more than the human mind alone ever could, science yields a way to write stories much wilder than fiction. All one needs to access the alien world of microbes around (and inside) them is a shift of scale by simple glass sphere.
I'm currently finishing up my undergraduate degree in Vancouver and in transition career-wise, hopefully to end up in graduate school soon. I was born in Russia (and speak the language) and spent most of my life in US and Canada. In addition to protists, I'm fascinated by evolution, including that of culture and languages, diversity and biology of cells and how they self-organise, linguistics and anthropology, particularly of the less talked-about cultures, sociology of science and plenty of totally random things that snag my attention.
Banner image was kindly post-processed and enhanced by my friend: an accomplished comic artist who goes by Achiru.

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