The genetic alteration of plants and animals by people is nothing new ; though artificial selection, we have influenced the genetic makeup of our livestock and crop plants for thousands of years Our ancestors altered the gene pools of our domesticated plants and animals through selective [traditional ] breeding by preferentially mating individuals with favored traits so that offspring would inherit those traits . Early farmers selected plants and animals that grew faster, were more resistant to disease and drought, and produced large amounts of fruit, grain, or meat.
Proponents of genetically modified (GM) crops often stress this continuity with our past and say today, s GM food will be just as safe as selectively bred food. Dan Glickman, head of the USDA from 1995 to 2001 , remarked:
“Biotechnology,s been around almost since the beginning of time. It,s cavemen saving seeds of a high-yielding plant. It, s Gregor Mendel,the father of genetics, cross-pollinating his garden peas. It ,s a diabetic s insulin,and the enzymes in your yogurt… Without exception,the biotech products on our shelves have proven safe.”
However, as critics are quick to point out, the techniques geneticists use to create GM organisms differ from traditional selective breeding in several ways. For one, selective breeding mixes genes from individuals of the same or similar species, whereas scientists…routinely mix genes of organisms as different as viruses and crops, or spiders and goats. For another, selective breeding deals with whole organisms li3ving in the field, whereas genetic engineering works with genetic material in the lab. Third, traditional breeding selects from combinations of genes that come together on their own, whereas genetic engineering creates the novel combinations directly. Thus, traditional breeding changes organisms through the process of selections, whereas genetic engineering is more akin to the process of mutation.