Another common definition of biotechnology is that it refers to techniques used to modify the genetic material of a microorganism, plant, or animal in order to achieve a desired trait. This, again, makes biotechnology an ancient practice, because humans have long known that if you mate two individuals with a certain trait, you’re more likely to get that trait in the offspring. Over 8700 years ago, people in Mexico’s Central Balsas River Valley had selectively bred teosinte, a wild grass, until it became maize, a far more nutritious crop.

Photo by Nicolle Rager Fuller, National Science Foundation
Modern corn has large cobs with large kernels, and is a rich source of nutrition. Modern corn is a result of selective breeding of teosinte, a wild grass. By choosing which seeds to plant, ancient people were able to increase the amount of nutrition yielded by each plant.

Dog breeds are another striking product of selective breeding. Current science suggests that dogs evolved from a population of wolves domesticated sometime between 20,000 and 40,000 years ago. Selective breeding of dogs has continued to affect the ways various dog breeds look and behave.

A Chihuahua mix and a Great Dane more than 50 times its mass.

Learning Objectives

- 1.1 Explain how biotechnology has positively affected humanity.