New Zealand is a black sheep among nations. Having spent the last 60 million years isolated from the rest of the continents — longer than any other major land mass — life has had a long time to do its own thing here. The vast majority of native trees and animals are found nowhere else. They’ve all learned their own tricks for contending with their unique surroundings. In particular, many birds, including the iconic Kiwi, found no reason to bother flying because there was nothing on the ground that would eat them.
An important lesson from a clever plant
One of the more unusual New Zealand plants is the Lancewood. Most of the specimens you’ll encounter look something like a tall broomstick decorated with menacing, saw-like leaves. They are rigid and serrated, and angled downwards towards you or any other potential assailant.
The Lancewood has a very bizarre feature: It completely transforms itself after reaching a certain level of maturity. Its long, toothed leaves give way to more lush, more conventional broad leaves. It actually begins to look like other trees. The plant’s two forms are so unlike each other biologists once thought they were two totally different trees.
Biologists couldn’t understand why a plant would evolve to do that. When an organism develops a distinct quirk like that, there tends to be an evolutionary reason for it. In other words, it must help the life form out somehow.
Some scientists guessed that the serrated, downward-pointing leaves served as a defence against large, ground-dwelling plant-eaters while it was still small enough to be vulnerable. But there was a problem with this theory: New Zealand doesn’t have any large, ground-dwelling plant-eaters. The island nation doesn’t have any native land mammals at all, only chicken-sized flightless birds that couldn’t pose a threat to a plant that size.
The Lancewood’s odd behavior remained a mystery for some time.
In 1839, a natural history enthusiast named John Harris was given an unusual bone fragment by a Maori who had found it on a river bank. He was quite taken with the unusual characteristics of the bone — it looked like a large femur, but he knew there were no large native animals on New Zealand’s islands. Eventually it made its way to the paleontology department at the British Museum, where experts puzzled over it for years before concluding that it belonged to a gigantic, now-extinct bird that must have once roamed New Zealand.
Maori tales had long refered to a great mythical bird they called Moa, and this appeared to fit the description. Since then thousands of Moa bones have been uncovered and now there is no doubt that a large flightless bird — up to ten feet tall; not unlike Big Bird in scale — once indeed roamed the isolated island group we now call New Zealand.
It turns out the Moa — actually several different species — all went extinct sometime around 1500AD, primarily due to hunting by the indigenous Maori people.
The Lancewood’s bizarre adolescence suddenly made sense. There was a creature large enough threaten the slender Lancewood, so it evolved a strategy to foil its beaked adversary. The rigid, downward-pointing barbs of the juvenile Lancewood would have made it quite unpleasant for a Moa to stick its face into the boughs to eat it. Presumably, the giant birds would learn to ignore the eye-gouging Lancewood in favor of plants that didn’t fight back.
Once the young Lancewood had grown to a height that was out of reach for the 3-meter Moa, it would be free to become what it always aspired to be: a splay of rich, leafy boughs that would be much more efficient for facilitating the tree’s growth and reproduction.
If this is true, it creates an interesting scenario. This plant continues to enact a defense mechanism against a threat that has not existed for centuries. Each Lancewood spends a patient 15 to 20 years in juvenile form before transforming and hitting its adult growth spurt.
It looks as if its stubborn anti-Moa feature is now only a liability. The Lancewood seems to invest considerable resources keeping itself safe from attack throughout its teenage years; it would likely grow much faster if it was willing to grow full, sun-catching boughs early on. To this day, each individual Lancewood pays the handsome price of a few years’ growth to combat a problem that hasn’t existed since Shakespeare was alive.
It might not have outlived its feathered nemesis had it not been so dedicated to thwarting it. The Lancewood’s obsolete ace-up-the-sleeve had its time, and did its job well, but now it’s just dead weight.
It will probably take hundreds of thousands, or even millions of years, for the Lancewood to adapt to the abrupt disappearance of the Moa — by laying down its arms, so to speak. Incidentally, Lancewoods are not found in great numbers, the way some of its less cautious competitors (namely ferns and beeches) are.
The Lancewood carries in its present-day behavior a relic of a bygone era. There are no Moa today, yet each specimen dutifully braces itself for an invasion of giant birds that will never come.
What our defense mechanisms are doing to us
I think the Lancewood’s scenario is similar to our own. It must now contend with the side-effects of its defense mechanism, even though it no longer confers a benefit.
Modern humans also bear the cross of costly behaviors that suit a bygone era better than the current one. Civilization has changed the playing field dramatically for nearly all of us, and so rapidly that evolution hasn’t a hope of keeping up.
A prime example is the abundance of food for those of us in developed countries. For most of history’s people, finding enough food trumped virtually all other concerns. But those of us born and raised in abundant, “first world” societies have never encountered any real danger of starvation. Getting enough calories is no problem for us. The problem now is stopping ourselves from getting too many.
Our bodies are still built from genetic information that assumes an ever-present danger of starvation. I don’t know about you, but my mind tells me to eat more than is really good for me. I have to be aware of this tendency and consciously restrain myself, or I’ll gain a lot more fat than I can use.
It’s actually quite a difficult impulse to deal with. Most Western countries have obesity problems. We find ourselves contending with an ancient urge to overeat whenever it is possible — and it’s almost always possible. Every year there are magazine articles and blog posts about how to get through the decadent Christmas season without putting on ten pounds, as if it just happens to us in spite of our wishes. Now we are defending ourselves from our defense mechanisms!
Handling the overeating defense mechanism alone makes for a lifelong struggle for many people. And it’s by no means the only one that causes us grief. Evolution’s residual side-effects have left us more than a little out of whack. A few more examples of defense mechanisms gone awry:
We get needlessly upset over losing face. Looking silly now and then doesn’t have a lot of long-term effect on our lives, though we often regard embarrassment like it’s a life or death matter. If we happen to make fools of ourselves, we won’t be cast out of the tribe to die in exile — but our ancestors might have been, and so today we remain disproportionately afraid of being judged.
We get needlessly attached to possessions. We have a very visceral attachment to our things, because in the past they represented our ability to survive. Today few material losses are truly pivotal. You can buy another one. Tear up a twenty dollar bill (less than an hour’s work for the average Westerner) in front of others, and listen to the gasps. Just dropping an ice cream cone on the sidewalk almost feels like you’re getting kicked in the heart. Imagine if we could let material things come and go freely, fully aware that we’ll be just fine, without that unpleasant yank on the heartstrings.
We get needlessly worried about controlling outcomes. We fret that we’ll miss the start of the movie, that the Colts will blow the Superbowl, that we won’t get this or that particular job, when at the end of the day we’ll still find ourselves alive and well, still enjoying loads of advantages and luxuries. The suffering caused by these little instances of uncertainty is often minor, but it’s still suffering, and proves to be rather needless when we realize there was never anything crucial at risk. Not getting what we want won’t kill us, but we still seem to ache for things to go a certain way. Imagine if we didn’t so easily let our preferences become burning needs whenever life and limb isn’t at stake.
The human’s unique advantage
But we humans are a clever bunch, and there is a ray of hope. Unlike the Lancewood, human beings are self-aware, which means we can look at our behavior and take steps to alter it if it isn’t really that helpful.
I think this is where we’re at in terms of our evolution. We’re built to do certain things, and now we must consciously do other things — ones that we might not be so good at, or that might not feel so immediately natural to us — but which won’t lead us to disaster like our impulses might if they remain unchecked. Following our instincts without question is exactly how we get into trouble these days. Addiction, self-destruction, violence, greed — nearly all of it born from unexamined, outdated human instincts.
Without this kind of self-observation and self-improvement, we’ll continue to suffer from our own outdated defense mechanisms until one of two things happens:
1) We hang on in our dysfunctional state for the millions of years it will take our biology to evolve beyond our current humanitarian woes, or
2) We go extinct.
Being a plant, the Lancewood can’t make decisions, so it’s bound to do what its genes tell it, whether that spells prosperity or death for its species.
Human beings have a say in what happens to them. The looming threats of overpopulation and climate change promise rapidly changing living conditions in our near future, and I think our troublesome impulses are going to make things even harder for us as time goes on.
So it really comes down to how we contend with what Mother Nature tells us to do. I believe if we really look at where our instincts take us, we’ll find we’re often better off disobeying Her. When it comes to survival — let alone quality of life — she doesn’t always know best. Or perhaps she eventually does, but she changes her mind very, very slowly.
Photos by David Cain and peganum