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Ciliate gluttony (again)

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


Frontonia are a large, gluttonous species of ciliates, which makes them a wonderful, colourful, subject of microphotography. Despite the modest appearance of their mouth, they can swallow some impressively big prey -- the suture beneath the mouth can open to widen the engulfment. Essentially, the critter unstitches its belly to fit more in. Would be nice for exceptionally big dinners, eh?

You can see a clear, slightly bubbly, macronucleus -- a thick wad of its own DNA. Beneath the nucleus is a freshly engulfed diatom -- you can tell it's fresh by its intact state, particularly of its plastids. Above the nucleus is an example of what will soon happen to it -- dissolve in acid and enzymes of a digestive vacuole. This vacuole will soon be recycled back to the surface to dispose of the victim's remains. The membrane becomes part of the cell surface, and then "spent" as phagocytic vacuoles (newly minted food vacuoles) form at the mouth. A protist's circulatory system can be a little more exciting than ours, in a way.

Here's a labelled version for clarification:


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I haven't quite figured out the identity of the refractile crystaline blob near the centre, above the "mouth" (inside a vacuole). If anyone knows -- I'd love to hear it!

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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