Biodiversity is a key concept in the biological sciences. While it has its origin in conservation biology, it has become useful across multiple biological disciplines as a means to describe biological variation. It remains, however, unclear what particular biological units the concept refers to. There are currently multiple accounts of which biological features constitute biodiversity and how these are to be measured. In this paper, I draw from the species concept debate to argue for a set of desiderata for the (...) concept of “biodiversity” that is both principled and coheres with the concept’s use. Given these desiderata, this concept should be understood as referring to difference quantified in terms of the phylogenetic structure of lineages, also known as the ‘tree of life’. (shrink)

Biodiversity has become one of the most important conservation values that drive our ecological management and directly inform our environmental policy. This paper highlights the dangers of strategically appropriating concepts from ecological sciences and also of uncritically inserting them into conservation debates as unqualified normative landmarks. Here, I marshal evidence from a cutting-edge research program in microbial ecology, which shows that if species richness is our major normative target, then we are faced with extraordinary ethical implications. This example challenges our (...) well-received beliefs about biodiversity and it invites us to critically rethink the nature of this concept so that a more robust understanding of biodiversity and of its role in conservation policy could emerge. (shrink)