or artificial selection is when humans breed plants and animals for particular genetic characteristics. Humans have bred food crops from wild plants and domesticated animals for thousands of years.

to control human breeding so that people with the best genes would reproduce and thus improve the species. It was an optimistic school of thought with a profound faith in the powers of Science.

German scientists plan to clone and then breed this year genetically modified pigs to serve as heart donors for humans, based on a simpler version of a US-engineered animal used last month in the ...