Darwin’s second ‘abominable mystery’: trait flexibility as the innovation leading to angiosperm diversity

Summary The fact that angiosperms are so species‐rich and ecologically diverse – Darwin’s second abominable mystery – could be explained by their ability to ‘reinvent’ themselves by evolving functional traits repeatedly over time, space and taxonomic clades. These trait innovations may facilitate adaptation and increase diversification rates. In this article, I quantify this ‘trait flexibility’ by reviewing the literature on trait transition...