Ancient biotechnology

Biotechnology can be broadly defined as purposefully using or altering living systems, organisms, or parts of organisms to develop products or systems that benefit humankind.

Earliest examples of biotechnology

The earliest example of biotechnology is the domestication of plants and animals. Domestication began over 10,000 years ago when our ancestors started keeping plants as a reliable source of food. Rice, barley and wheat were among the first domesticated plants. Wild animals were tamed to provide milk or meat or help with ploughing or guarding the farm. The dog, sheep and goat are thought to be among the first animals that were domesticated.

Making new foods using biotechnology

Our early ancestors used microorganisms to make cheese, yoghurt and bread. They also made alcoholic drinks like beer and wine. All of these foods and drinks are made by fermentation. Fermentation is the process that many microorganisms (yeasts, moulds and bacteria) use to convert sugars into energy. The products generated from fermentation affect the nature of the food that the microorganism is in - carbon dioxide causes bread to rise, lactic acid makes yoghurt sour, and alcohol is produced in the formation of beer and wine.

Fermentation was probably discovered by accident, and our early ancestors didn’t know how it worked. Some societies thought fermentation was a miracle or gift from their god.

Louis Pasteur first described the scientific basis for fermentation in the late 1800s. Pasteur’s hypothesis, called the germ theory, showed the existence of microorganisms and their effect on fermentation. Pasteur’s work gave birth to many branches of science.

Traditional medicines

Some traditional medicines also used organisms or parts of organisms. For example, the ancient Egyptians used honey for respiratory infections and as an ointment for wounds. Honey is a natural antibiotic, killing the germs in wounds.

By about 600BC, the Chinese were using mouldy soybean curds to treat boils. Similarly, Ukrainian peasants were using mouldy cheese to treat infected wounds. The moulds released natural antibiotics that killed bacteria and prevented the spread of infection. Despite these natural treatments, it wasn’t until 1928 that Alexander Fleming first extracted penicillin – the first antibiotic – from mould.

Examples of selective breeding

Early pioneers of selective breeding mated organisms with desirable traits to enhance these traits in their offspring. Selective breeding pioneers were manipulating the genetic makeup of organisms, without even realising it.

Corn is a dramatic example of a plant that has been enhanced by selective breeding to become a better source of food. Early teosinte plants (about 5000BC) had small cobs with few kernels, but by 1500AD, the corn cobs were more than 5 times the size and packed full of sweet, juicy kernels.

Dog breeds are another example of selective breeding. There are more than 100 breeds of dog, all resulting from selective breeding. Dogs were bred for specific jobs and to enhance traits such as size, shape, agility and colour, resulting in breeds from the tiny Chihuahua to the Great Dane.

The discovery of genes

A monk named Gregor Mendel identified genes as the unit of inheritance in 1865. It took another 90 years of research before the structure of DNA was described in 1953. This discovery was the beginning of modern biotechnology.