Crazy Chlorophyll-Using Sea Slug Is Part Animal, Part Plant

By Andrew Moseman | January 13, 2010 4:39 pm

seaslugPart animal, part plant, bright green, and totally bizarre: Meet the sea slug Elysia chlorotica.

Biologists already knew that this organism, native to the marshes of New England and Canada, was a thief that somehow pickpocketed genes from the algae it eats. At last week’s meeting of the Society for Integrative and Comparative Biology in Seattle, researcher Sidney Pierce said he has found that the slugs aren’t just kleptomaniacs—they use the pilfered genes not only to make chlorophyll, but also to execute photosynthesis and live like a plant. Said Pierce: “They can make their energy-containing molecules without having to eat anything,” Pierce said. “This is the first time that multicellular animals have been able to produce chlorophyll” [LiveScience].

The slug steals in a different way than most organisms (usually bacteria) that employ horizontal gene transfer to incorporate the DNA of others. Most of those hosts tuck in the partner cells whole in crevices or pockets among host cells. Pierce’s slug, however, takes just parts of cells, the little green photosynthetic organelles called chloroplasts, from the algae it eats. The slug’s highly branched gut network engulfs these stolen bits and holds them inside slug cells [Science News].

By using detectors to trace small amount of radioactivity, Pierce says he confirmed that the slug was actually using the stolen genes to produce the chlorophyll itself rather than snatching already-made chlorophyll from the algae. In addition, parent slugs pass on the genetic pathways for chlorophyll and photosynthesis to their offspring, showing it becomes incorporated into their genes.

Once again, nature reminds us, evolution can be wonderfully creative. “This could be a fusion of a plant and an animal — that’s just cool,” said invertebrate zoologist John Zardus [Science News].

Related Content:
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The Loom: Going Green

Image: Nicholas E. Curtis and Ray Martinez

  • Dave

    Either this slug is from Europa, or it’s the Swamp Thing.

  • Brian Too

    It’s a planimal!

  • George H

    This would be great if it could be developed into a product which could make this work with Humans. Think about the implications on “space travel” or even emergency situations. or persons who have disorders where there normal ability to eat is comprimised stomach cancer, etc… its very exciting.

  • danielvucetic
  • Chris TMC

    Brian Too- ever watch MST3K?
    George H- ever watch Farscape?

    I sound like a couch potato slash nerd, but those are the first two things I thought when I read your posts lol.

    Seriously though, interesting article! :)

  • D. D’Agostino

    I believe humans have already been able to do this to some extent. They are known as autotrophs and there are supposedly around 3000 of them in existence. There is not clear published scientific evidence about this yet, but I can think of three examples:

    1.)Therese Neumann (Apr.08, 1898-Sept.18, 1962) – the German mystic who consumed no food apart from the Host for almost 40 years. She would take in sunlight every day. This is perhaps one of the first humans able to carry out the photosynthesis process. Surely if we had had the technology then we have today we could have tested this.

    2.) Prahlad Jani (78), an Indian holy man, stopped to eat and drink when he was 8 years old. He surprised all the world by proving that this holy man doesn’t need to consume not even water.

    3.) Hira Ratan Manek (66), an Indian engineer, who hasn’t eaten nor drunk for 8 years. Hira (HRM) can be found at both and at (the forum). For the past 2 years scientists at his Solar Healing Center have been studying volunteer Sungazers. Recently, feeling confident of the data they have collected and reviewed over this 7 year timeframe, the scientists have submitted proposals to NASA and NIH.

  • blue

    waw that is awesome i wish i could see that plant animal one day…….

    e cigarette

  • lucy

    can’t agree more ….evolution can be wonderfully creative…..and also Nature is the art of God -it’s fascinating and crazy,and we are part of it…..

    electronic cigarettes

  • CW

    Maybe this will evolve into E.T., wasn’t that a plant-animal?

  • Shaking head

    @ D.D Agostino:
    Why don’t you tell people in eithiopia? I’m sure they will belive you..

  • It’s people!!

    when we detail how the slug metabolizes the energy gained from light, and passes it into his body, we will have one helluva diving suit! How about utilizing chloroplasts to power machinery? What a freaky world.

    DD- just don’t send the breathairians a check..

  • Jumblepudding

    So..possible path for human evolution if global warming doesn’t let up. Literally going green.

  • Brian Too

    It ain’t easy being green (ref. Kermit).

  • danielvucetic

    read the links i posted, they are very interesting

  • WakeUpInBioClass

    Danielvucetic and D. D’Agostino, I read all the links posted and it was all fascinating, thank you so much!!
    Whether you agree, or believe, or whatever, I suggest that everybody check out the links. Especially if, like me, you aren’t a very experienced student of biology yet; danielvucetic’s articles are extremely well explained, and actually clarified a few things that I took notes on in class but didn’t really absorb properly. And D. D’Agostino’s articles are undeniably fascinating and controversial. They ARE scientific inquiries that are relevant to the topic, so don’t attack him, please :)
    Everything I have just read is just incredibly exciting. The possibilities that modern research opens up are mind boggling. All of today’s top scientists are either changing the world or explaining it as it changes itself before our eyes. We live in an age that the history books will remember.

  • Dave E.

    I find this interesting more for the fact that it shows life can come in many forms. What, where, and under what conditions could life exist? And should we hold Earth as the only mold for life? Who knows? The possibility of what could be is beautiful.

  • Alex Procel

    I agree Alex Procel

  • Michael J. Helmus

    Symbiotic relationships are found everywhere on our planet… Furthermore I would argue that these relationships are necessary for our survival as well as our ‘hastened’ evolution. Let me explain a little bit in more detail by giving you all two well known examples (that might have slipped by). The first is that all humans have bacteria living within our gut (enterobacteriaceae). These little bugs are actually necessary towards our survival as they create amino acids that we ourselves are incapable of creating. The second example relates to the beginning of life (debatable of course but this is the most excepted theory to date). Within the cells of our body, and that of all other multicellular organisms, are energy producing organelles known as mitochondria. Mitochondria have their own DNA that is separate from that of DNA located within the nucleus (it would be like comparing apples to oranges… IE: the DNA is very different in composition and heritage). Based upon this information (and much more information that I cannot recall at the moment) it is hypothesized that there once was a single celled organism that cannibalized another single celled organism to obtain its mitochondrion. HUGE advantage evolutionarily speaking… instead of finding very specific “food” molecules it was then able to create its own energy from non-specific macromolecules.

  • Sally J.

    Someone needs to show this to Kirk Cameron! (No examples of intermediate evolutionary life forms – my arse. EVERYTHING is an intermediate evolutionary life form!)


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