With all the attention on climate change (and about time), it is easy to forget that there are other global environmental threats which will harm human health and the well-being of all human societies this century. In my view, the one that stands out is the biodiversity contraction that is presently underway.
It is incredible to think that the term “biodiversity” only came into existence around 1986. Since then, the field has opened up enormously and we have learnt a great deal about the web of life, and the functioning and evolutionary history of the natural world. Biodiversity occurs at many levels. Diversity within populations, within species and within and between ecosystems are all important aspects.
There are certain links with climate change of course. Mid-range “business as usual” global warming is predicted to contribute to the extinction of maybe 1/3 of all living species this century. Similarly, there are some common contributors to both dilemmas, for example the loss of forests. Of course, there have been five previous extinction events throughout pre-history, although this one differs in at least two ways. Firstly, the pace of species loss has never been greater. It is thought we are running at between 100 and 1000 times the background or “natural” rate of extinctions. Secondly, it is entirely unprecedented that one species should come to dominate almost every conceivable ecosystem and biological niche. This should worry us greatly, even if just from a selfish perspective.
The drivers of lost biodiversity include – land use change, the spread of exotic pests and weeds, climate change, pollution and poisons, industrial mono-cultural agricultural systems, trade in endangered animal products, gross over-fishing. There are many other indirect drivers.
The health consequences of biodiversity loss will include the loss of medicinal plants and medical models, the emergence of infectious diseases, and weakened global food production. Critical declines in ecosystem services (the things nature does for us) can be expected – water purification, break-down of waste and pollution, pollination, sequestering carbon and so on. We shouldn’t forget the psychological harms of a degraded biosphere, loss of amenity, aesthetics, and sense of place. Ethical considerations also speak to us profoundly. What right do we as a species have to inflict this on the remainder of the world’s living creatures? It is immensely unethical. Extinction is forever.
Australia’s record is worse than any other continent. Since European colonisation, we have lost 19 species of mammals alone, and another 10 exist only on offshore islands after being once widespread on the mainland. We must be particularly careful given that 80% of our plants and animals are found nowhere else in the world. Yet we can walk into any nursery in this country and buy plants known to be frequent garden escapees and noxious, invasive weeds.
In the end, we must remember that saving “life” will take more than a few focussed zoo breeding programs. If the habitat is gone, many such animals could be regarded as the “living dead”. We must target the key drivers head on. It is particularly urgent given that – like climate change – there will be a big lag between action and results. A certain number of extinctions are “built-in” and inevitable no matter what we do from here on. Fortunately, many of the actions that mitigate against climate change also help biodiversity. A holistic approach will be needed and environmental concerns must inform every decision we make, at individual, community, national and international levels – just as economic considerations do now.
So let’s get started.
Use soft words and hard arguments