Anthropogenic global changes (i.e. climate and land-use change) are causing high rates of extinction and migration of species, reshuffling biodiversity worldwide and threatening ecosystem functioning. However, understanding the consequences of biodiversity change is usually hampered by our lack of knowledge on how different biodiversity facets (i.e. taxonomic and functional diversity) change across spatial and temporal scales. In this presentation, I will discuss how the dark diversity concept – set of currently absent species that could potentially inhabit a study site – can enhance the way we track and mitigate biodiversity changes.