June 2025

The concept of biodiversity loss is absolutely integral to conservation, and I have never met anyone who has seriously challenged the idea that too many species are going extinct, nor that their extinction is a result of human pressures. So, what do we make of multiple studies telling us that we shouldn’t be focusing so much on biodiversity loss? These studies say that, on average in samples across the world, roughly equal numbers of sites are increasing in species richness and decreasing.

Maria Dornelas is the ecologist, from the University of Lisbon and the University of St Andrews, at the centre of this research and she joins me to elaborate. It should be mentioned right at the start that Maria is not suggesting that biodiversity loss is not a problem, but she explains why she thinks we are doing conservation a disservice by focusing on it the way we do. Maria emphasized the importance of nuance in conversations about conservation, and this discussion is an illustration of the importance of avoiding too much generalization and simplification.

Links to resources:

• Looking back on biodiversity change: lessons for the road ahead - 2023 article by Maria and colleagues.

• Assemblage Time Series Reveal Biodiversity Change but Not Systematic Loss - Maria's 2014 paper in Science, which announced the surprising results of her research.

• BioTIME - Global database of assemblage time series for quantifying and understanding biodiversity change.

• Inside Biodiversity - Related IDIV podcast that is referenced in the intro to this episode.