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With c. 24 700 species (10% of all flowering plants), Asteraceae are one of the largest and most phenotypically diverse angiosperm families, with considerable economic and ecological importance. Asteraceae are distributed worldwide, from nearly polar latitudes all the way to the tropics, and occur across a diverse range of habitats from extreme deserts to swamps and from lowland rainforests to alpine tundra. Altogether, these characteristics make this family an outstanding model system to address a broad range of eco-evolutionary questions. In this review, we summarize recent progress in our understanding of Asteraceae on the basis of joint efforts by specialists in the fields of palaeobotany, cytogenetics, comparative genomics and phylogenomics. We will highlight how these developments are opening up new possibilities for integrating fields and better comprehending evolution beyond Asteraceae. [ABSTRACT FROM AUTHOR]

Summary: The replacement of seed‐free plants and gymnosperms by flowering plants during the Cretaceous is one of the most important biotic events in the evolution of life. However, the magnitude of this global turnover remains largely unknown.Here we present sampling‐standardized diversity estimates from a high resolution palynological record of the Late Cretaceous (85–66 Ma) from Antarctica, in the context of the past climatic events.Our fossil evidence reveals the occurrence of a rich Campanian flora peaking at c. 80 Ma, with angiosperms as the most diverse group of plants for the first time in Antarctica. This peak of diversity was followed by a period of a stepwise deterioration; 60% of ferns and 40% of gymnosperms became locally extinct from the early/mid‐Campanian to the late Maastrichtian. Although angiosperms also faced several extinctions – 25% became extinct – they were far less affected than nonangiosperms.The onset of deterioration of the greenhouse conditions at the end of the Cretaceous – low CO2 and global cooling trends – would have led to our observed pattern of change. Overall, our study reveals the beginning of a profound floristic turnover in the highest southern latitudes that pre‐dates the major extinction event of the end of the Cretaceous by 15 Myr. [ABSTRACT FROM AUTHOR]

The Asteraceae (sunflowers and daisies) are the most diverse family of flowering plants. Despite their prominent role in extant terrestrial ecosystems, the early evolutionary history of this family remains poorly understood. Here we report the discovery of a number of fossil pollen grains preserved in dinosaur-bearing deposits from the Late Cretaceous of Antarctica that drastically pushes back the timing of assumed origin of the family. Reliably dated to ~76-66 Mya, these specimens are about 20 million years older than previously known records for the Asteraceae. Using a phylogenetic approach, we interpreted these fossil specimens as members of an extinct early diverging clade of the family, associated with subfamily Barnadesioideae. Based on a molecular phylogenetic tree calibrated using fossils, including the ones reported here, we estimated that the most recent common ancestor of the family lived at least 80 Mya in Gondwana, well before the thermal and biogeographical isolation of Antarctica. Most of the early diverging lineages of the family originated in a narrow time interval after the K/P boundary, 60-50 Mya, coinciding with a pronounced climatic warming during the Late Paleocene and Early Eocene, and the scene of a dramatic rise in flowering plant diversity. Our age estimates reduce earlier discrepancies between the age of the fossil record and previous molecular estimates for the origin of the family, bearing important implications in the evolution of flowering plants in general. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Early evolution of the angiosperm clade Asteraceae in the Cretaceous of Antarctica" in the 2015 issue is presented.