psychohist wrote:
Does genetic engineering count as a "circumstance"? Does it count as evolution?
Interesting question. We generally exempt human selective breeding from the term 'evolution,' so GE would be exempt from the term as well; however, if GE genes get into wild populations and are then either weeded out by nature or spread and become fixed, that would be evolution.
For example, pure black canines are a human invention, but back-breeding introduced the gene into wolves and it is now positively selected for in timber wolf populations.