The delicate web of biodiversity

Published Tuesday, October 29, 2013 in the New Brunswick Telegraph Journal.

Several years ago I remember reading that wolves had been reintroduced to Wyoming’s Yellowstone National Park and that aspen trees were making a comeback as a result.  It seemed odd – a feared carnivore helping out a tree? – but it’s a simple example of the interconnectedness of life on this planet, and the importance of every species.

The details

What was happening in Yellowstone was actually the result of some straightforward biological relationships.  Wolves had been hunted to local extinction in the 1920s.  In their absence, the local elk population had burgeoned.  That put pressure on aspen trees, a favourite food of the elk, to the point where most aspen saplings were eaten clean and died before they had the chance grow beyond the reach of the elk.  The reintroduction of the wolves trimmed back the elk population to previous levels, and aspen trees started recovering as a result.

The point is this: in our complex ecosystem of millions upon millions of species, it’s easy to overlook or underestimate the value of any single species, especially if it’s not cute, local, prominent or part of the human food chain.  But every species, even an obscure or ugly one, plays a role – and often, a far bigger role than we might imagine.  The loss of one species can lead to a domino effect of unintended or unanticipated consequences.

Critical biodiversity

A vast, deep and diverse spectrum of life is critically important.  All around us but mostly out of sight, species of all types quietly perform vital functions that keep our ecosystem strong, stable and resilient.

For example, wetlands, with their complex network of life, perform vital water purification services.  Microorganizms may not be very sexy, but the sewage treatment lagoons of the world would soon be bunged up if not for the free waste processing services they provide.  Silently but constantly, forests and ocean plankton draw carbon dioxide from the air.  

Even the slugs I curse in my garden have a vital role in converting the organic matter on the forest floor to usable plant nutrients.

And there’s a more serious side to biodiversity.  Much of our food comes from plants that depend on bees and other pollinators.  Many of the drugs we use to fight sickness and disease originate from plants and it’s a safe bet that there are many more out there yet to be discovered.

A biodiverse ecosystem is like an enormous, well-tuned machine with millions of parts, quietly humming along synchronously.  

Biodiversity under pressure

Unfortunately, human activities are putting unprecedented pressure on our ecosystem and many of its inhabitants.  It’s estimated that species are being lost at a rate 100-10,000 times the natural background rate, mostly because of global deforestation, habitat loss, overexploitation, the introduction of invasive species and climate change.  Many of those factors operate synergistically.  For example, new roads for forestry also provide access for overhunting.

What to do?

Just as the largest of machines depends on each of its parts, a strong ecosystem depends on each of its components.  So what can we do to help keep our planet’s incredible biodiversity machine humming?

First, we’d do well to better appreciate the interconnectedness and interdependence of all species, us included.  In today’s society, it’s easy to become disconnected from the natural world, and even to believe that we are somehow above it.  But the words of Chief Seattle are as true today as they were 150 years ago: “Man does not weave the web of life; he is merely a strand in it.  Whatever he does to the web, he does to himself.  All things are connected.”

Then we need to act accordingly.  Buddhism and Hinduism teach of Ahimsa – ‘doing no harm’ – and not killing or injuring living beings.  That’s a lofty ideal, but we can take ourselves a long way down that path simply by making lifestyle choices that cause less habitat destruction, less overhunting and overfishing, less pollution, less energy consumption: in short, less of anything that hurts the wellbeing of our fellow passengers on Earth.