Monday, September 20, 2010

Avatar's New Twist on Plants

Director James Cameron released Avatar in December of last year after spending four years creating what can be deemed nothing short of an epic masterpiece of a movie. Not only was it hailed as the groundbreaking 3D release of its time, it has effectively set an entirely new standard by which all blockbusters are measured. Although I can only speak for myself, after spending a little over two and a half hours with the Na’avi people on Pandorain a pure, unmitigated visual and auditory experience I was in sheer awe.
I’m under the impression other viewers felt the same, and although I didn’t quite experience the surprisingly common “post-Avatar-depression” that some did (their support blog can be found here:, I can’t help but assume that anyone who has seen this movie was at least a little intellectually provoked. For me, it was the biological and ecological design of Pandora and its inhabitants that consumed my thoughts for the following weeks after leaving the theater. I just kept thinking myself in circles, ultimately coming back to the thought: “somewhere, in some time, could this be possible?” Conveniently, for my first blog entry, I found an article that addresses this very question in regard to the terrestrial life on Pandora.From the very beginning, however, this article points out that these terrestrial beings were most certainly not "plants" by the Earth definition of the word.

On Pandora, the plants glow, shoot poison leaf tips, communicate with each other, and serve as messengers from the spirits of greater beings. Jodie Holt, a physiologist from the University California, explains that if the plants that make up the lush rainforest environment of Pandora had been too bizarre, viewers would have dismissed them as unreal. In the minds of viewers, the fact that Pandora could potentially exist as a planet adds an entirely new dimension to the movie. Hence, the extreme reactions to the film mentioned above.

One of the most fascinating plants on Pandora is the "helicoradian". It's this orange, spiraled plant that folds up when touched. According to Holt (who acted as a "botany consultant" for Mr. Cameron) plants on Earth can display this kind of touch sensitivity, however, it is greatly exaggerated in the helicoradians on Pandora. This exaggeration of Earth characteristics is an ongoing theme for the terrestrial life in Avatar.
Yet in the article, Holt admits that since there is really no one characteristic that distinguishes plants from other life kingdoms; it makes it rather ambiguous for her to consider a characteristic as being “exaggerated” within the plant kingdom.

Holt goes on to explain that she didn't invent any new vegetation for the film, but rather, described certain plant characteristics and then left it up to what was known about Pandora’s environment to simulate what kind of features would be advantageous, to mock the natural selection that may have occurred, had Pandora been a real place. There turned out to be a lot more science, creativity, and calculation that went into this than most viewers would otherwise have expected. Aspects of Pandora including the soil, and atmospheric composition, and weak gravity and high magnetic fields were all taken into consideration for each plant species. From the dynamic of life on Pandora, Holt gave certain characteristics to the plants that an Earth-like species may have adapted should it have been placed under the similar stresses of a Pandora-like environment. For example, Holt explains that gigantism (the sheer height of the majority of the trees on Pandora) would have been likely to occur due to the higher levels of atmospheric carbon dioxide and lower gravitational pull on Pandora compared to Earth. The bioluminescence (glow) that some of the plants were capable of giving off could be explained by the long periods of darkness experienced on Pandora.

However, of most importance to the terrestrial life on Pandora was the ability of the plants to communicate with each other. Unfortunately, in the article, Holt states with extreme certainness that: “there is absolutely no way this could happen.” She explains that the only trait that could ever resemble this is single transduction - seen in terrestrial plants on Earth. Signal transduction is the capability of plants to communicate within their structures to consolidate the use of water in periods when it is not abundant. Like, when a root is not getting enough water, it will "tell" the leaves that it feeds to wilt until water becomes available again. To go from signal transduction, to actual communication between plants is quite an evolutionary stretch, and was certainly not as realistic of a quality as other aspects of terrestrial life on Pandora.

In conclusion, I was really impressed to read about the technicality involved in designing the terrestrial life of Pandora. I loved the movie, so I really would’ve been in to any article that offered even a remote explanation of the potential for life like that on another planet. I know that the science points to no, but I still believe that theoretically, a planet like Pandora could exist somewhere else. Who is to say that evolution occurs the same on Earth as it would elsewhere? Maybe in a non-carbon based environment, mutations occur more readily, or the time between generations is faster, allowing more natural selection to occur compared to evolution in our "Earth years". Regardless of if these are legitimate considerations, I like to thinks its possible….

1 comment:

  1. Hi Galia,
    Thanks for the introductory article; it's a good first introduction to the types of issues that will be central in astrobiology. In particular, it raises the question of how one actually visualizes what an alien world is like, something that Cameron and his team have clearly done a great job in bringing to the screen.

    There are two aspects of the movie that I'd like you to think more on in terms of the choice of flora (and fauna) on Pandora.

    The first is something you mentioned but did not then expand upon. As it turns out, the characteristics of the creatures highlighted in the movie are actually *not alien enough* to be realistic! This is partly an artistic choice: a planet of slime-mold-like creatures with hexapodal Na'avi would simply not have been as relatable to as characters or as an idyllic world in peril. However, it's interesting to note that the choices here were comparatively tame, compared with the choices in geology or physics (levitating rock formations?)

    The second aspect relates to the planetary scale sentience that is a central "character" in the movie; you mention that Holt dismisses this in terms of existing communication, but are there other problems with this idea? How fast would signals propagate, how much energy would it take? On a related note, the idea of a "planetary level" superorganism is not new--did you think of looking back at the Gaia hypothesis original proposal?