Nature or manufacture: What should we fear most?

Of very ancient descent, domestication switched the outcome of natural selection to that due to human design. A widespread fancy is that man-created contraptions develop dangerously on their own because of their Promethean essence. This assumes implicitly-how difficult is it to refrain from thinking that we are the sawyers of nature!-that their crafted powers would dominate the autonomy resulting from billions of years of evolution. Yet artifice depends on the skills of its creator, so that it is when coming close to nature that danger surfaces. Invasive species are natural, and the havoc they create is here to call for some modesty in the appraisal of our endeavours. The farther away, the less dangerous. Being distant from man, engineered plants are considerably less harmful than animal constructs, especially those that are close to man and meant for medical use. This reality contrasts with popular belief. In this misconception lies the danger, magnified by the present demographic explosion of the invasive species Homo sapiens, which develops artificial environments that provide progressively less room for life to evolve. (C) 2016 Academie des sciences. Published by Elsevier Masson SAS.