How is biodiversity threatened and how can we protect it?Biotechnology - Crop modification and novel foods

Biotechnology is the use of living organisms to develop or make products that help us. This is quite a broad definition and many different organisms or processes are involved. Humans have used biotechnology for thousands of years in agriculture and used selective breeding to produce better foods and medicines. More recent examples of biotechnology include cloning and genetic modification. Biotechnology can help us meet the food demands of our ever increasing population.

Crops directly feed us or animals we keep for food. They are commonly cereals, fruit and vegetables. We can change (or modify) crops in two key ways - selective breeding and genetic modification.

Selective breeding

For thousands of years farmers have instinctively known what animals to breed together, for example breeding a big bull and a big cow to have big calves. This is selective breeding. It occurs when animals or plants with a desirable characteristic are selected to breed with each other. Because of inheritance, their offspring are likely to have the desired characteristic. Over generations these characteristics have become enhanced.

All breeds of dog belong to the same species. They were all originally bred from wolves. Dogs have been bred for a variety of reasons including protecting livestock, hunting, providing company and for their different shapes, sizes and colours. They have all been selectively bred for these different characteristics.

Many crops have been selectively bred to have greater yields.

Other specific examples include:

1. Friesian cows to produce large volumes of milk and Jersey cows to produce creamy milk.
2. Wheat that is resistant to some diseases.

Genetic modification

Scientists can now identify the genes in some species that control some characteristics. These genes can be removed using enzymes and inserted into the genome of other individuals within the same species or those in other species. This is genetic modification (or engineering). The organism that has been modified is called transgenic.

Golden rice is a variety of rice that has been genetically modified to contain beta-carotene which helps people who do not get enough vitamin A in their diet. This deficiency disease kills over half a million children each year. We have also genetically modified soybeans and corn to include beta-carotene.

Other crops have been genetically modified to be resistant to insects. A bacterium called Bacillus thuringiensis naturally produces a toxin which kills many insects. The gene responsible for this has been identified, removed and inserted into crop plants. This removes the need for farmers to use insecticides on their crops, which have negative impacts on the environment.

Other crops have also been genetically modified to be resistant to herbicides. Some plants are naturally resistant to herbicides. This gene has been identified, removed and inserted into crop plants. This means that farmers can spray whole fields with herbicides and kill just the weeds, not the crops.

Some people disagree with genetic modification. They have concerns that it might harm human health and others worry that the genes might spread to other species. Currently, there is no scientific evidence to support these concerns.