Abstract The relationship between human health and biodiversity, the living part of nature, is well documented and complex. While biodiversity is a threat in that it incorporates a reservoir of diseases and vectors, it is also an essential source of active molecules complementing the direct services that ecosystems contribute to the health and wellbeing of humanity. All things considered, biodiversity is a major factor in the health of humanity. And yet, current state of knowledge in the environmental and life sciences emphasises the sometimes dramatic erosion of biodiversity, in particular due to the pressure of anthropic activities, and the new magnitude of human contributions to biodiversity. In proposing ethical reflection on the relationship between humanity and biodiversity and, more generally with nature, CCNE is first of all mindful that humanity itself is a part of biodiversity. Its position in the midst of biodiversity and its capacity to alter biodiversity for the worse make it necessary to effect a change in the relationship that humanity constructs with the living world. Ethical reflection on the subject therefore resides in an analysis of the consequences of our actions or even, more fundamentally, in an analysis of their causes, that is to say the way we interact with other members of humanity and with all life on earth. CCNE believes that an ethical course of action in the life and health sciences must include drawing public attention and debate to the causes of the persistence of poverty and hunger in the world and to the increase in relative impoverishment and health issues related to impaired biodiversity, demographic expansion and the escalation of migratory flows. Within the living world, humanity’s particular accountability entails an obligation to call into question the concept of progress hitherto equated with increasing control over that world. This accountability primarily falls upon the scientific community where a more unassuming approach could help to gain a better understanding of the links between biodiversity and health in the context of the inherent unpredictability of interacting dynamic processes, in particular those related to biological evolution. At a time when genome transforming biotechnologies are increasingly effective and readily implemented, fostering a responsible ethical attitude to scientific and technical activities is an essential priority. Sharing more effectively the sum of scientific knowledge with political decision-makers and society as a whole, while contributing to the questioning of its applications, is a major ethical challenge. The protection and use of biodiversity require a somewhat more complex ethical analysis than the sole objective of conservation, all the more so because the degradation of biodiversity must frequently be correlated with the precarious situations in which many human communities find themselves. An ethical approach and solidarity must be deployed in conjunction if the issue of long-term management of natural resources is to incorporate the prospects for fighting poverty. The time has come to cast aside the utopia of nature at humanity’s disposal and to replace it by a search for the synergies between possible forms of human development allied to recognition for the dynamic processes of ecosystems, both at a local level and through global governance instruments which are yet to be discovered. This can only happen if people, including the scientific community, are committed to the task of identifying courses of action leading to relevant legislative change. Based on such ethical reflection, this report seeks to determine the pathways to rational coevolution of humanity and life on earth so as to preserve its potential for wellbeing and health.