Pioneers and settlers scrabble for life like a lone bush colonising motorway concrete

In the middle of the motorway, between the lanes, nestled against a barrier post, a lone little bush hangs onto the concrete against the Wellington winds. The first people who came here were like that.

In the plant world, the toughest, woodiest plants get into a crack and cling on to marginal life, or not, depending on chance. In their shelter and around their roots, life builds up. Soil and humus hold moisture. The wind goes over the top. More delicate plants move in to lead a more complex and comfortable life, creating a complex interlock of dependency we call an ecosystem.

In the human world, the grittiest, most desperate characters colonise a new land. They scratch away at a bare existence, or not. Crops fail. Weather attacks. Disease takes already-weakened bodies. Slowly fences and walls go up. Water is managed. The soil is worked. New generations build on the work of the old, and communities grow in complexity, wealth and interdependence.

The difference is they know. People know the risks they are taking. They know life is better somewhere else. The little tree doesn't. Why do people scrabble and slave? Some have no choice. They are destitute or run-aways. Some are reclusive and accept the hard life as the price for solitude. Others thrive on the challenge, pushing themsleves to the extremes.

I like to think most pioneers are motivated by something else: the desire to build something better for their descendants. They endure as a gift to their offspring. Less nobly, Richard Dawkins would say it is The Selfish Gene at work, ensuring its perpetuation. Whatever the driver, their heroism or just plain doggedness is often extraordinary.

Two of my great-grandfathers went to sea at thirteen as cabin-boys, and came ashore on the other side of the world. What possessed a boy to take on the hardest, most dangerous life there was, never to see family again? Imagine how it was when a few dozen Maori came ashore in the first canoe, exhasted from months at sea, stores depleted, tempers frayed, to face sub-tropical forest, freezing rain, and unfamiliar hunting. The Chinese and European gold diggers lived in tents in the deep frosts of Central Otago, far from doctors or police. What gies through a settler's mind when he faces a new patch of bushland, armed only with an axe and a firelighter and a spade? Prioritising shelter, food, water and defence while developing the land is the most mission-critical management task imaginable. The stakes are survival of you and your family.

Pioneers are as tough and plucky as that little tree hunkered down on the motorway, but what is more they know better, and they know their likely fate, and still they endure.

As a result of their effort and sacrifice, I grew up in a community where an individual can make all they need to survive. I asked little of my parents and I have no need to build a legacy for my son. He is smart and agile enough to build his own environment. We are orchids on the forest floor, safe and grateful.