Wednesday, June 14, 2006

The Art of Ecological Research and Strangulation

Yesterday we walked through secondary forest with an assignment to identify interesting questions we could imagine researching in just a few days. Lots of fascinating forest ecology stories were told including the delicate mechanics of orchid pollen exchange, but the focus was on the development of research questions. Having no background in research, this was for me a wee bit of a challenge, but this first step in question development seems to be about pursuing any given wonderment with a mixture of rigor and imagination. What I have less of is the knowledge to inform my wondering… having a sense for the fundamental dynamics that, in a given context such as this secondary forest, will give rise to questions about how those dynamics might manifest or how certain phenomenon might be explained.

So for instance, what forces drive variation in activity level in the monkeys of Costa Rica? Now a bit of context: Howler monkeys are relatively sedate, spider and the white faced monkeys have intermediate mobility, and squirrel monkeys are highly mobile. And now some theory: resource availability, competition, maybe even reproduction (we’re back to sex again!) all might play a role. So what specific questions might I ask to understand the variation? I might hypothesize that it has something to do with resource availability (variation in diet) and, perhaps further, specialization of diet from competition. Now I can survey the populations and observe eating habits directly or indirectly (say through their poop! Or should I say “scat”). I might also create an experiment to directly test my hypothesis, changing the normal patterns I observe in some decisive way that lends itself to illuminating measurement. I see the logic and beauty in this approach, so fundamental to knowledge but so new to me in such an elementary form. From there, the software developer in me is comfortable, if only conceptually, with the engineering problems of experiment design and execution: think of ways to answer the questions, define a design, look for and address potential defects, all the while being ready to change strategies when necessary. I can see that there's an art to experiment design, one that takes talent and dedication to develop.

And now to the art of a strangulation. Along the walk we came across a huge strangler fig (family moraceae, genus ficus) a plant with an amazing strategy for establishment. The parent strangler fig produces fig fruits that get eaten by, oh, say, by a spider monkey. The seeds, if all goes well, find a happy environment in the niche of a tree in the canopy and germinate, dropping roots from the canopy the forest floor, possibly far below. Where before nutrients were extracted from the host tree and growth was slow, the fig now sustains itself on ground nutrients and grows quickly in a lattice around the trunk of the host tree, upwards towards the canopy. The host and the fig now compete for precious light and ground nutrients, but the fig also “strangles” the host, constraining its nutrient flow and growth. Eventually, the host dies and rots inside the lattice structure, providing further nutrients for the victorious fig. I imagine there might be cases where the fig is overly ambitious, killing its host tree before it’s fully established and able to maintain structure, so there is perhaps an art to the timing of the kill. On our walk yesterday morning, we came across an example of a successful strangulation: a hollow tunnel to the sky where the host once lived.

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At 10:56 AM, Anonymous Anonymous said...

Mwah hah hah. Our evil plan to bring you over to the science division is working.

Glad you are having fun and learning. Say "hi" to Peter for me.


At 12:26 PM, Anonymous Anonymous said...

Hey Kristin - Are you able to reach this communication vehicle now? What happened to your computer and if you get this, how in the world did you restore it?
Loving and MISSING you!!!