Good example of artificial selection

[Phobos]

http://www.cnn.com/2003/TECH/scienc...n.ap/index.html

Ancient Americans were changing corn genes through selective breeding more than 4,000 years ago…

…researchers found that three key genetic variants were systematically enhanced, probably through selective cultivation, over thousands of years.

…The ancestral plant of corn, teosinte…was a grassy-like plant with many stems bearing small cobs with kernels sheathed in hard shells. By cultivating plants with desirable characteristics, farmers caused teosinte to morph into an increasingly useful crop.

…"The differences between maize (corn) and teosinte come down to just a few genes, but with big effect,"

I think this provides a good example of how genetic codes can be altered to produce dramatic changes in a species. Much in the same way that cabbage, kale, broccoli, cauliflower, and Brussels sprouts all were derived (evolved) from a single wild plant species or how all modern domesticated dog breeds were derived from wild wolves.

 

[Ygggdrasil]

Since the link in the OP was broken by the forum's automod, here's a currently working link to the story from 2003: https://www.cbsnews.com/news/modified-food-dates-to-ancients/

The news story likely refers to this 2003 paper in Science: https://science.sciencemag.org/content/302/5648/1206

In the intervening 16 years, more work has been done to study corn domestication, such as the following two papers:
Genomic estimation of complex traits reveals ancient maize adaptation to temperate North America
https://science.sciencemag.org/content/357/6350/512
Multiproxy evidence highlights a complex evolutionary legacy of maize in South America
https://science.sciencemag.org/content/362/6420/1309