Recent advances in molecular phylogenetics and a series of important palaeobotanical discoveries have revolutionized our understanding of angiosperm diversification. Yet, the origin and early evolution of their most characteristic feature, the flower, remains poorly understood. In particular, the structure of the ancestral flower of all living angiosperms is still uncertain. Here we report model-based reconstructions for ancestral flowers at the deepest nodes in the phylogeny of angiosperms, using the largest data set of floral traits ever assembled. We reconstruct the ancestral angiosperm flower as bisexual and radially symmetric, with more than two whorls of three separate perianth organs each (undifferentiated tepals), more than two whorls of three separate stamens each, and more than five spirally arranged separate carpels. Although uncertainty remains for some of the characters, our reconstruction allows us to propose a new plausible scenario for the early diversification of flowers, leading to new testable hypotheses for future research on angiosperms.

Adaptive radiation is one of the most emblematic concepts in evolutionary biology. However, the current lack of a consensual definition and the diversity of methods used to assess the extent and speed of adaptive radiation indicate the need for a reappraisal of this research field. In order to depict how adaptive radiations have been studied in recent years, we performed a scientometric assessment of 765 articles published between 2003 and 2012 in five journals known to serve a broad audience. From each study, we extracted and analyzed data relative to the taxon and geographical area investigated and to the methodological setup, and we categorized its outcomes and conclusions. This scientometry-oriented work allowed us to identify and discuss trends relative to the way research about adaptive radiations was carried out during the 10-year period starting in 2003. We then provided some recommendations for how to conduct a reliable study of a suspected adaptive radiation. The associated database resulting from our study will be a valuable source of information for biologists as they design a study or put their results in perspective. Our work may also inspire a critical assessment of the relevance of this pivotal concept in evolutionary biology.