How development affects evolution
The modern evolutionary synthesis of the 1930s and 1940s unified Darwinian evolution and Mendelian inheritance. Since then, many researchers have called for an analogous synthesis between evolutionary and developmental biology, arguing that the lack of such synthesis has limited evolutionary understanding.
I formulated a mathematical framework that integrates evolutionary and developmental dynamics, yielding deep insights into how development affects evolution. The framework sharpens Wright’s principle — according to which adaptation by natural selection occurs such that the population climbs the fitness landscape — showing that development provides the admissible evolutionary path and invariably induces hard constraints on adaptation. This means that development generally has major evolutionary effects, contrasting with long-held views.
Image modified from González-Forero. 2023. Evolution. 77, 562-579. Paper.
Brains have evolved into a stunning diversity across the animal kingdom giving rise to an even more stunning diversity in behavior. What drives brain evolution? We developed a mathematical model to help address this question.
Using this model, we have found that cognitive ability and brain mass can be mechanistically related by a simple equation. We have also found causal, computational evidence suggesting that human brain expansion may have been driven by ecological and cultural factors, rather than social factors such as cooperation and competition, contrasting with dominant hypotheses.
In major evolutionary transitions, groups of individuals become higher level individuals, which has had major effects on life on earth. What causes such major transitions?
We have developed mathematical models to study a classic hypothesis that posits that one such major transition, i.e., eusociality, arose from ancestral maternal manipulation. The hypothesis suggests that workers in eusocial organisms evolved because mothers manipulate their offspring to become helpers. Although this hypothesis attracted interest in 1970s, evidence has since been interpreted as rejecting it because it was thought that manipulation would lead offspring to resist whereas eusocial offspring seem to help voluntarily. We have found that manipulation may evolve while resistance fails to evolve for various reasons, so eusociality can evolve from ancestral manipulation yielding voluntarily helping offspring, consistently with various patterns observed in eusocial taxa.
Species are key units for evolutionary inference and conservation policies, but they are infamously difficult to define. I developed a formalization of the biological species concept and explored its consequences.
I found that one formal interpretation of this concept overcomes various difficulties of the verbal concept, but in doing so populations can belong to multiple species.