Aim Despite several recent efforts to map plant traits and to identify their climatic drivers, there are still major gaps. Global trait patterns for major functional groups, in particular, the differences between woody and herbaceous plants, have yet to be identified. Here, we take advantage of big data efforts to compile plant species occurrence and trait data to analyse the spatial patterns of assemblage means and variances of key plant traits. We tested whether these patterns and their climatic drivers are similar for woody and herbaceous plants. Location New World (North and South America). Methods Using the largest currently available database of plant occurrences, we provide maps of 200 × 200 km grid‐cell trait means and variances for both woody and herbaceous species and identify environmental drivers related to these patterns. We focus on six plant traits: maximum plant height, specific leaf area, seed mass, wood density, leaf nitrogen concentration and leaf phosphorus concentration. Results For woody assemblages, we found a strong climate signal for both means and variances of most of the studied traits, consistent with strong environmental filtering. In contrast, for herbaceous assemblages, spatial patterns of trait means and variances were more variable, the climate signal on trait means was often different and weaker. Main conclusion Trait variations for woody versus herbaceous assemblages appear to reflect alternative strategies and differing environmental constraints. Given that most large‐scale trait studies are based on woody species, the strikingly different biogeographic patterns of herbaceous traits suggest that a more synthetic framework is needed that addresses how suites of traits within and across broad functional groups respond to climate.

We are living in a time of rapid environmental changes caused by anthropogenic pressures. Besides direct human exploitation of plant and animal populations and habitat transformation, biodiversity changes in the Anthropocene are affected by less trivial processes including rapid spreading of non‐native species, emergence of novel communities and modifications of ecosystem functioning due to changing nutrient cycles and climate changes. These processes are so complex that confident predictions and effective biodiversity conservation cannot be obtained without a suitable theory of biodiversity dynamics. We argue that such dynamics have particular attractors, i.e. stable equilibria, that are determined by environmental conditions. These stable equilibria set biodiversity limits, i.e. carrying capacities for biodiversity, from local to global scales. We point out the evidence of such limits at various spatiotemporal scales and show, using the new equilibrium theory of biodiversity dynamics (ETBD), how dynamics of diversity depend on non‐linear relationships between number of species, community abundance and population size‐dependent processes of species extinction and origination (speciation or colonization). We show that non‐linear effects of biodiversity on ecosystem functioning can lead to multiple biodiversity equilibria and tipping points. Various human activities, including species introductions, human appropriation of primary production and trophic downgrading, can change local, regional and global diversity equilibria by affecting processes that set equilibrium diversity levels. The existence of equilibrium and out‐of‐equilibrium states has important implications for conservation, restoration and reconciliation ecology. It highlights the need to more effectively and intentionally balance the historical focus on the preservation of natural habitats with management specifically directed towards the processes responsible for long‐term maintenance of biodiversity equilibria. The Anthropocene represents a unique situation in which people make decisions concerning the dynamics of the natural world, and we argue that ecological restoration requires wisely deciding which of the alternative equilibria are worth maintaining.

The trophic interactions between plants, insect herbivores and their predators are complex and prone to trophic cascades. Theory predicts that predators increase plant biomass by feeding on herbivores. However, it remains unclear whether different types of predators regulate herbivores to the same degree, and how intraguild predation impacts these trophic interactions. Despite past syntheses having confirmed cascading effects of vertebrate predators on terrestrial arthropods, we lack a more comprehensive look at the effects of other predators on a global scale. Here we report a meta-analysis of 486 experiments gathered from 157 publications reporting the effect of insectivorous vertebrates (birds and bats) and ants on abundances of predatory (spiders, ants, others) and herbivorous (chewers and others) arthropods; on arthropod richness and plant damage. Generally, the absence of vertebrate predators led to the increase of predatory arthropods by 18%, herbivorous arthropods by 75%, and plant damage by 47%. In contrast, after the removal of ants, the increase in the abundances of other predatory arthropods did not compensate for missing ants, herbivore arthropods increased their abundances by 53%, and plant damage increased by 146%. The effects of ant exclosures were stronger in communities at lower elevations and latitudes, while we did not detect any clear geographical patterns in the effect of vertebrate exclosures. Neither precipitation nor NDVI had a significant impact on most of the measured effects, and the effect of exclosures was robust for both plant growth forms and different habitat types. We found vertebrate insectivores to be the more dominant predators of arthropods, but we detected that the strength of their trophic cascades was weakened by intraguild predation. On the other hand, we found that although ants were relatively less dominant as predators, and their influence was detectable only in the most productive sites, the effect of trophic cascades on plants they caused was stronger than that of vertebrate insectivores.