Selected list of publications (my first author papers)

Intuitive and broadly applicable definitions of niche and fitness differences, J.W. Spaak and Frederik De Laender, 2020
We introduce new definitions of niche and fitness differences that can be applied to a much more general collection of community models. Importantly, these definitions align with intuition and can be applied to mutualistic communities.

Fitness differences, not niche differences, limit species richness, Jurg W. Spaak, Camille Carpentier, Frederik De Laender, 2021
The basic result is simple (and worthwhile to retain), species richness increases fitness differences increase (Panel B), but niche differences (Panel A) are not affected. Species richness is therefore limited, because the species move “upwards” towards coexistence boundary (Panel C)  Twitter feed with main results

Mapping species niche and fitness differences for communities with multiple interaction types, Jurg W. Spaak, Oscar Godoy, Frederik De Laender, 2021
We use niche and fitness differences to map species interactions. This map allows cross community comparisons and serves as a common currency between different fields. We also show which part of the map are well explored (competitive communities and priority effects) and which deserve more attention (facilitation and higher trophic levels). Twitter feed with main results

Effects of pigment richness and size variation on coexistence, richness and function in light limited phytoplankton, J.W. Spaak, F. De Laender, 2021 Journal of Ecology
We simulate light limited phytoplankton communities and compute their species richness, niche and fitness differences and ecosystem function. The positive effect of trait richness on ecosystem function and species richness is initially strong, but coexistence requirements reduce trait richness and therefore the positive effect vanishes over time. Twitter feed with main results

Niche differences, not fitness differences, explain predicted coexistence across ecological groups, L. Buche, J.W.Spaak, J. Jarillo and F. De Laender, 2022 Journal of Ecology
Really cool work with my former master student Lisa Buche (go and check her out). She did a huge metanalysis of all empirically measured niche and fitness differences. Interestingly, the data can be clustered in mainly two clusters, one with high niche differences, which contains essentially all coexisting species pairs. And one with low niche differences, without coexistence. Fitness differences appeared to be much less important (yes, I know this is different than the finding in my multispecies paper). Twitter feed with main results

Google Scholar, Jurg W. Spaak, Po-Ju Ke, Andrew D. Letten, Frederik De Laender, 2022, OIKOS
We review the large variety of different methods to assess niche and fitness differences (more than 13 methods) and group them into 3 loose groups. We then go on to show that these methods lead to very different interpretations of which process is important or what actually stabilizing means. However, we currently do not have the tools to evaluate which of these methods are the best, but we do offer criteria to potentially evaluate this in the future. Twitter feed iwth main results