No Chokky for Your Kids? – Why You Should Care About Biodiversity
Imagine a world without chocolate. It could happen. It’s the kind of world your children or your grandchildren might grow up in.
Chocolate is made from cocoa. Cocoa grows on cocoa trees, which grow wild in the Amazon in South America. Commercial varieties of cocoa trees have been bred from the original Amazon plants, and they are now grown in many tropical countries.
But, like all crops, commercial cocoa suffers from pests and diseases things with strange names like the ‘cocoa pod borer’, ‘witches broom’, ‘black pod’ and ‘swollen shoot’. Growers stay one jump ahead by constantly cross-breeding their commercial cocoa varieties with wild, naturally resistant types.
It’s like an arms race: each time the cocoa diseases are beaten back they evolve some new way to attack the trees. And each time breeders dip back into the jungle reservoir of wild cocoa to find some newer, tougher form of resistance.
Without that reservoir of wild Amazon cocoa varieties, the growers would have little to fight the diseases. But each year forest felling eats deeper and deeper into the native range of the cocoa tree.
For chocolate lovers the message is clear. You need more than just a good cocoa plantation to keep the supply of chocolate flowing. You also need to preserve a large slice of the cocoa tree’s original wild home as an insurance policy against future crop diseases. Cocoa grows on plantations, but its insurance grows in the Amazon rainforest.
Chocolate is not alone. All the world’s crops were once bred from wild plants, maybe thousands of years ago. Wild varieties of crops like wheat, corn, soybean, rice and oats can still be found in their original homes, and scientists are constantly cross-breeding commercial varieties with these undomesticated strains to stay a jump ahead of the myriad of diseases which afflict modern agriculture.
But as humans spread ever further, the original homes of these important plants are shrinking, as are the original homes of all wild plants and animals.
Wild plants and animals are very different from domesticated varieties. Domestic plants and animals are bred to be all very like each other high-yielding, fast-growing and efficient. A paddock of farm wheat is all one variety, each plant exactly the same as all the others. Most of Australia’s wheat crop each year is usually a single, genetically identical variety.
In the wild it’s different. Just as some people have blue eyes and some people have brown eyes, plants and animals all have individual variations. It is this variety or genetic diversity which is a farmer’s most precious resource. And all over the world this wild diversity is being rapidly replaced by domesticated sameness.
Most Australians probably don’t realise it, but Australia is home to some native plants and animals which are very important for world agriculture. None of the world’s major crops or farm animals originated from Australia, of course, although there are plenty which might one day – seeds from Australian wattles, for example, are already being used in Africa to feed hungry people. Emu, yabby and crocodile farming are all fast-growing industries. Australian Macadamia trees are grown around the world.
But Australia is home to many native relatives of important world crops. Not wild varieties, but related species distant cousins, if you like.
To take just one example: there are at least 16 native Australian plants which are distant cousins of soybean. Some of the Australian plants grow in conditions far too dry and salty for soybeans, and some are resistant to diseases which plague soybean growers. Scientists have already had some success in cross-breeding soybean with these Australian plants, trying to breed varieties of soybean which can grow in dry conditions, poor soils and which are resistant to disease.
Australia has an estimated 475,000 species, most of which live nowhere else in the world. And there is a lot of genetic variation within each of those species. Who knows what species, or what variety, might come in handy one day? Who knows what life-saving drugs might one day be extracted from Australia’s native plants and animals?
Thousands of organisms which at first seem to have nothing to do with humans grubs in the ground, floating plankton way out at sea, trees growing in distant forests all actually help clean and recycle the air, water and soil that we depend on for our survival.
Never before has biodiversity been so much under threat. All over the planet, including in Australia, humans are changing the environment to make way for houses, farms, roads and other developments. The creatures which lived there before usually don’t survive.
You can’t conserve biodiversity in a zoo all you could hope to save would be a few big animals. Conserving biodiversity has to be everyone’s responsibility. The CSIRO is now mounting a major research effort to learn more about Australia’s unique biological heritage, and how best to preserve it.
Last year the Convention on Biological Diversity came into force around the world an international agreement to conserve biodiversity. Australia has joined it, so have more than 50 other countries. In line with the Convention, Australia’s Federal, State and Territory Governments are expected to announce soon a joint national strategy.
Author: David Mussared
Source: Department of the Environment and Water Resources.