Will species continue to evolve or do they reach a point where evolution ceases (stasis)? In 1973, Leigh van Valen posed the hypothesis that species keep evolving to keep up with the evolving species in their environment. This is called the Red Queen Hypothesis, after the Red Queen in Lewis Carrol's Through the Looking Glass who said so Alice: "Now, here, you see, it takes all the running you can do, to keep in the same place". Even though the hypothesis is old, it is not know under what conditions species evolve of reach stasis. Theoretically, we found that a combination of a positive and a negative feedback can lead to continual evolution.
Experimentally, I study how species interaction affect evolution using a system of a bacteriovorous roundworm Caenorhabditis elegans and a bacteria Escherichia coli. In the video below I explain how I use this system to study the predictability of evolution.
As predicting evolution is becoming more popular in different subfields, we came together with a large group of scientist of various backgrounds to write a review on "The why, what and how of predicting evolution across biology: from disease to biotechnology to biodiversity".
We have shown that we can caracterise metabolic pathways that optimize growth and that we can use that to understand that the trade-off between growth rate and yield is condition dependent. The use of many of these pathways allow for the use of the metabolites for other species, and therefore cross-feeding interactions. These interactions are abundant in the gut microbiome, and we study some of these interactions in more detail to understand the dynamics of the microbiome in disease.
To understand evolution, it is great that we can study evolution in real time in the laboratory. When interpreting the results of these experiments, we have to understand well what the selection pressure in laboratory environments are. In a theoretical analysis, we have shown that the chemostat environment can lead to diversification. More recently, I have shown that in fluctuating conditions, species specialized on either low or high resource levels can coexist in an evolutionary stable manner.