This Code was used in the transcriptome analysis The evolution of convex trade-offs enables the transition towards multicellularity Joana P. Bernardes, Uwe John, Noemi Woltermann, Martha Valiadi, Ruben J. Hermann, Lutz Becks*
corresponding author: lutz.becks@uni-konstanz.de
The evolutionary transition towards multicellular life often involves growth in groups of undifferentiated cells followed by differentiation into soma and germ-like cells. This is facilitated by trade-offs between traits determining survival and reproduction, favoring the coexistence of cells with extreme trait values and a convex trade-off curve as the multicellular state dominates. However, these transitions remain poorly characterized at the ecological and genetic level. Here, we studied the evolution of cell groups in ten isogenic lines of the unicellular green algae Chlamydomonas reinhardtii with prolonged exposure to a rotifer predator. We confirmed that cell groups were heritable and characterized by a convex trade-off curve between reproduction and survival. Identical mutations evolved in all cell group isolates which were linked to survival and reducing associated cell costs. Overall, we show that just 500 generations of predator selection were sufficient to lead to a convex trade-off and incorporate evolved changes into the prey genome.