1 Stage projection (Lefkovitch) matrices for 21 species of woody plants and 45 herbaceous perennials were extracted from the plant demographic literature or compiled from published data. 2 Each matrix was divided into six regions representing: 1, recruitment of seeds to the seed pool; 2, recruitment of seedlings or juveniles from current seed production; 3, clonal growth; 4, retrogression, due to plants decreasing in size or reverting in stage; 5, stasis, (survival from one year to the next in the same stage class); 6, progression to later stage classes. 3 Matrix analysis was used to calculate the finite rate of increase X for each population and to calculate the elasticities of each transition coefficient in the matrices. Elasticities were summed within each of the six regions of the matrix to give measures (E1 -E69 respectively) of the importance of each component of the life cycle to X and fitness. 4 Herbs as a group differed significantly from woody plants in most of these components. Seedling recruitment was more important in herbs than woody plants. Retrogression occurred only in herbs, particularly those with a tuber. Stasis occurred in nearly all species, but was most important in woody plants. Progression was more important than fecundity in almost all species. 5 Trade-offs among life cycle components were determined from correlation matrices of r (= ln X) and elasticities E1 -E6 for the whole sample and for herbs and woody plants separately. As a whole, r was positively correlated with elasticities for fecundity (E1 + E2) and growth (E3 + E6) and negatively correlated with survival (E4 + E15). In clonal herbs, fecundity and clonal growth were negatively correlated. 6 The division of elasticities into three major components (growth, G = E3 + E6; fecundity, F = E1 + E2; and survival, L = E4 + E5) allowed us to construct triangular plots in G-L-F space. This was done separately for iteroparous forest herbs, iteroparous herbs from open habitats, semelparous herbs and woody plants. Each of these four groups occupied a distinct position in G-L-F space. Within woody plants, shrubs of fire-prone habitats occupied the end of the distribution with the lowest survival elasticity. 7 It is argued that the demographic approach to the classification of distinct ecological groups offers new insights into the relationship between life history and habitat.

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Human metapneumovirus (hMPV) is a respiratory paramyxovirus that is distributed worldwide and induces significant airway morbidity. Despite the relevance of hMPV as a pathogen, many aspects of the immune response to this virus are still largely unknown. In this report, we focus on the antiviral immune response, which is critical for viral clearance and disease resolution. Using in vitro and in vivo systems, we show that hMPV is able to induce expression of lambda interferon 1 (IFN-1), IFN-2

Vegetative dormancy, that is the temporary absence of aboveground growth for ≥ 1 year, is paradoxical, because plants cannot photosynthesise or flower during dormant periods. We test ecological and evolutionary hypotheses for its widespread persistence. We show that dormancy has evolved numerous times. Most species displaying dormancy exhibit life-history costs of sprouting, and of dormancy. Short-lived and mycoheterotrophic species have higher proportions of dormant plants than long-lived species and species with other nutritional modes. Foliage loss is associated with higher future dormancy levels, suggesting that carbon limitation promotes dormancy. Maximum dormancy duration is shorter under higher precipitation and at higher latitudes, the latter suggesting an important role for competition or herbivory. Study length affects estimates of some demographic parameters. Our results identify life historical and environmental drivers of dormancy. We also highlight the evolutionary importance of the little understood costs of sprouting and growth, latitudinal stress gradients and mixed nutritional modes.