It's All Relatives

Illustration above taken from Geometric Designs for Artists and Craftspeople by Dover Publications, which is nice enough to give away free samples of its clip art.

A POPULAR SAYING BACK IN MY COLLEGE DAYS, when we were first breaking free of the moral absolutes our parents had tried to teach us, was "It's all relative." Much later in life, when I began to learn about ecology and such, I changed what by then had become a cliche into a phrase that I can still live by. And so today I often announce, "It's all relatives."

In other words, everything is connected to everything else. This is hardly news to anyone the least bit familiar with ecology or natural history, but the specific examples never cease to inspire interest--and, in me at least, something akin to awe.

The paradox of protection
One such example came up recently in a study published in Science magazine. In this research, scientists working in Kenya fenced off whistling thorn trees (a type of Acacia) so that the trees could no longer be eaten by elephants and giraffes.

Now, it might seem that protecting the trees from huge plant-eating mammals would be a good thing to do. But after about 10 years of this, the trees were all dying off.

It turns out that the Acacias ordinarily provide good habitat for a particular type of ant. The trees provides food and shelter, in return for which the ants attack any animal that tries to eat the trees' leaves.

Once they were fenced off, however, eventually the trees got lazy and stopped providing the right habitat for the friendly ants. As a result, these ants were replaced by other ants, which had no interest in defending the trees. On the contrary, these new ants have a mutually beneficial relationship with a type of wood-boring insect, which soon took up residence in the Acacias.

Eventually the health of the Acacias began to be undermined by the wood-boring beetles and other insects that were able to invade now that the friendly ants were gone. And so the Acacias started to die.

For want of an ant ...
The trees were, quite literally, being killed by kindness.

Fencing off large predators caused the loss of their tiny defending army, leaving the trees exposed to far worse dangers than the occasional elephant or giraffe. Invisibly to human eyes, relationships that had evolved over thousands of years had been preserving the health of the trees. Yet as scientist Todd Palmer pointed out to writer Cornelia Dean in an article for the New York Times, it took only 10 years for this protective net to fall apart after humans intervened.

As Dean's article notes, scientists are finding similarly complicated relationships all over the planet. In North America, for example, research conducted in Yellowstone National Park found that wolves protect aspen trees by frightening off elk that otherwise would over-browse them. In its article on mutualism, the Wikipedia points out that gardeners sometimes try to create mutually interdependent relationships, as when we plant beans next to corn so that the beans can provide nitrogen for the corn while using the corn stalks as trellises.

It's (also) all relative
For wildlife-friendly gardeners and natural landscapers, stories such as these are reminders that we must not be too hasty to identify any creature as an enemy. One of my favorite examples, which I've talked about before, is aphids. Most gardeners kill them on sight, but they are one of the best bird foods in the garden, and if you want to attract birds, usually it's best to let those aphids live.

At one time most people in the West assumed that wolves were "bad" because they killed elk; now we know that the relationship between predator and prey, a., is more complicated than that and, b., affects many living things, not just the most visible participants.

Likewise, preventing a plant from being eaten might seem like the obvious thing for a plant-lover to do. But is it? Can we be sure?

Perhaps the best attitude to take toward any fellow creature is to acknowledge that, like all creatures, it has a role to play. Unless we know what that role is, best to proceed cautiously.

My own rule of thumb is that native species, having evolved together, are presumed to have relationships that are worth preserving. Non-natives, being new introductions, are less likely to be important in some larger drama that is currently invisible to me.

But even so, I try to remember to proceed carefully. After all, it's all relatives.

For more information on the research done in Kenya, see the BBC News or the Scientific American.

5 comments:

Gloria said...

Thanks for addressing this,I feel safer making a bit of a statement here where it will not be taken as a crusade to force all others into doing likewise.

Why does the use of native plants cause so much defensive attitude.
It seems as if only those avowed to not be EXTREME or PURIST are allowed to express an interest in a more natural style of gardening.
I like extremes,there are no beige or white walls in my home and the kitchen counter is RED.
What is so wrong with going into something whole heartedly.
If we are expected to be passionate about gardening why not habitat gardening?
It can be hard to decide what to do and what the limitations are. If I wait until spring to clear away debris should I wait until green is showing? Will moving it to a compost area remove the overwintering young too far a distance from host plant?
There are so many questions and so much to be learned. I applaud those willing to appear different to learn more and pass it on.
In my opinion we need more willing to make the jump to all native gardening not fewer. Can more damage be done than the lawn and clipped shrub crowd have already managed?
Thanks, I needed to say that...LOL

Wild Flora said...

You're welcome, Gloria. And believe me, I sympathize. I've noticed some of the same things you've noticed, and I have a lot of the same questions. A couple of decades ago when I was a journalist in Chicago, I was opinionated and outspoken and, if you can believe it, found that this approach was well received. Then in the early 1990s I moved to Seattle and everything changed. Was it the change from a Midwestern industrial city to the West Coast? Was it a change in the culture around that time? I still don't know, but I did find that suddenly being opinionated and outspoken was frowned upon. What had once been praised as passionate was now criticized as "trying to tell others what to do." Language that previously had been regarded as forthright was now regarded as rude. I ended up dong a lot of soul searching in the 1990s, and eventually came to the conclusion that my primary goal is to communicate with others, and so I have to try to communicate in whatever way others are willing to hear. So I started trying to write in a much more laid back style, and I try to remember to use humor as much as possible. This hasn't been easy -- I think that by nature I'm much more of a table banger and soap-box orator than anything else, and so it's a constant struggle to be mild-mannered. And I'm not even sure it's the right way to go; maybe in the long run, "be yourself" is always the best path. For the time being, however, I try to tell myself that this effort is good for my spiritual development--or as I prefer to call it, my #$$%$!!!*& spiritual development.

Gloria said...

Maybe this is just the way our species adapts. We talk about it, sometimes argue. Some yell and go to extremes while others try to ignore it or wait until something happens that must in the moment be dealt with. Some try a middle road.
It seeps into the culture, is fanned into huge proportions, then becomes excepted as a way of life or is rejected.
Maybe like the trees and ants and large animals all are necessary componets to the process, all are relatives...you have me thinking.

Wild Flora said...

Excellent point, Gloria! In fact it strikes me that when we acknowledge that every creature has a role to play, we also acknowledge that each role is different. Some of us are wolves, some of us are elk, some of us are aspens ... and some days I think I'm that little scrap of lichen on the rock the elk just pooped on! But we're all valuable, right?

jodi said...

I came back to re-read this post, and then the comments, on this fine Monday morning (it's cold, but sunny, so that's okay with me.) What I find is that I resent being preached at, whether by the religious set (when I used to go to church) or by the eco-nazis, as I call the real strident types who would rather we were all extinct and everything was natural again. Now, we both know that I'm seriously inclined towards organic gardening, native plants, pollinator/wildlife friendly gardening, etc, and have been for thirty years. But being preached AT will shut me down and in fact, throw up resistance in me. (I'm talking in this case of the garbage police, as I call them, who are just another layer of self-important bureaucrats who don't give a damn about the ecosystems, just about their own little fiefdoms.)
This attitude within myself colours my own writing. I worry about things like supporting local agriculture or gardening in an environmentally friendly way, but as the bees show us, we catch more creatures with honey than with vinegar. So I gently talk TO people, rather than AT them, and it does seep down through. People start to make more responsible changes and choices, because they choose to, not because they're legislated to. It seems to work. I take similar tactics that you do, proceding carefully both in the garden and in educating others. Hopefully it works. It seems to...