Mass extinctions and their rebounds: a macroevolutionary framework

Forest biodiversity world‐wide is affected by climate change, habitat loss and fragmentation, and today 20% of the forest area is located within 100 m of a forest edge. Still, forest edges harbour a substantial amount of terrestrial biodiversity, especially in the understorey. The functional and phylogenetic diversity of forest edges have never been studied simultaneously at a continental scale, in spite of their importance for the forests' functioning and for communities' resilience to future change. We assessed nine metrics of taxonomic, phylogenetic and functional diversity of understorey plant communities in 225 plots spread along edge‐to‐interior gradients in deciduous forests across Europe. We then derived the relative effects and importance of edaphic, stand and landscape conditions on the diversity metrics. Here, we show that taxonomic, phylogenetic and functional diversity metrics respond differently to environmental conditions. We report an increase in functional diversity in plots with stronger microclimatic buffering, in spite of their lower taxonomic species richness. Additionally, we found increased taxonomic species richness at the forest edge, but in forests with intermediate and high openness, these communities had decreased phylogenetic diversity. Functional and phylogenetic diversity revealed complementary and important insights in community assembly mechanisms. Several environmental filters were identified as potential drivers of the patterns, such as a colder macroclimate and less buffered microclimate for functional diversity. For phylogenetic diversity, edaphic conditions were more important. Interestingly, plots with lower soil pH had decreased taxonomic species richness, but led to increased phylogenetic diversity, challenging the phylogenetic niche conservatism concept. Synthesis . Taxonomic, phylogenetic and functional diversity of understorey communities in forest edges respond differently to environmental conditions, providing insight into different community assembly mechanisms and their interactions. Therefore, it is important to look beyond species richness with phylogenetic and functional diversity approaches when focusing on forest understorey biodiversity.

Biocrusts are major contributors to dryland diversity, functioning, and services. However, little is known about how habitat degradation will impact multiple facets of biocrust diversity and measurable functional traits. We evaluated changes in taxonomic, functional, and phylogenetic diversity of biocrust-forming lichens along a habitat degradation gradient related to the presence of linear infrastructure (i.e., a road) and a profound agricultural driven transformation. To do so, we selected 50 remnants of a Mediterranean shrubland. We considered several surrogates of habitat quality and causal disturbance on the various diversity facets of biocrusts by using structural equation modeling, hypothesizing that habitat degradation primarily affects functional diversity, which in turn regulates changes in taxonomic and phylogenetic diversities, and also that taxonomic and phylogenetic diversities are coupled. Fragment connectivity, distance to linear infrastructure (i.e., a road) and, particularly, soil fertility (i.e., soil P concentration), had mostly negative effects on biocrust functional diversity, which in turn affected both taxonomic and phylogenetic diversities. However, we found no direct effects of habitat degradation variables on the taxonomic and phylogenetic diversities. We also found that increases in phylogenetic diversity had a positive effect on taxonomic diversity along the habitat degradation gradient. Our results indicate that functional diversity of biocrusts is strongly affected by habitat degradation, which may profoundly alter their contribution to ecosystem functioning and services. Furthermore, functional diversity regulates the response of biocrust taxonomic and phylogenetic diversity to habitat degradation. These findings indicate that habitat degradation alters and simplifies the diversity of functional traits of biocrust-forming lichens, leading to biodiversity loss, with important consequences for the conservation of global drylands biodiversity.

The idea behind multimetric indices is to integrate information from several metrics to provide a general classification of water bodies without losing the particularities of each individual metric. Historically, multimetric indices use information on richness, taxon sensitivity, and taxonomic diversity. Recently, functional and phylogenetic diversity proved to capture different dimensions of biodiversity. Here we asked if these new metrics provide complementary information to classical metrics and should be included in multimetric indices. We used an index construction protocol based on statistical filters to test candidate metrics for range, sensitivity, and redundancy. We used macroinvertebrate data from streams located in a Savanna region of Brazil, encompassing a gradient of impact, to test our ideas. Of 41 candidate metrics, functional dispersion of functional diversity, mean nearest neighbor distance of phylogenetic diversity, and four classical metrics passed the filter selection composing the final multimetric index. Our results indicated that functional and phylogenetic diversity metrics indeed responded to environmental impact and complemented the information provided by classical metrics. We suggest that future indices should consider including new metrics of functional and phylogenetic diversity to properly monitor multiple dimensions of biodiversity.

Climate change and anthropogenic alteration of landscapes negatively impact the abundance and species diversity of plant and animal communities worldwide. Much less is known about the effects on phylogenetic diversity and community functioning. Here we use long‐term butterfly data (1980–2022) from the Austrian Alps along an elevation gradient. We assessed how communities adjust structures and functionality to increasing temperatures, and how these changes are linked to trait expression and community functioning. Species diversity decreased at low and intermediate altitudes, and increased at high ones. Functional diversity was lower than expected by a random model at intermediate and high altitudes and increased with time at high, but not at intermediate and low altitudes. Phylogenetic diversity did not show significant temporal trends at low altitude, but increased with time at intermediate and high altitudes. Multifunctionality significantly decreased at intermediate and high altitudes and was not significantly correlated with functional diversity, but was negatively correlated with phylogenetic diversity. We argue that the ongoing homogenisation of Alpine butterfly communities strongly affects species, functional and phylogenetic diversity. The assessment of species richness and diversity alone, as provided by common species surveys, might give a false impression about the state and functional diversity of Alpine insect communities in the course of climate change. The directions of faunal changes heavily depend on altitude and therefore on specific climatic conditions. Higher altitudes face decreasing butterfly multifunctionality despite of increasing species richness due to climate induced altitudinal up‐hill shifts of many species. We conclude that studies on community time series should include phylogenetic and functional diversity besides of being focused on richness and endangerment. Red lists might be extended by categories on functional importance and phylogenetic distinctness.

To assess the extent and coverage of ecosystem services, we need to know their geographic distributions. These are typically estimated using environmental data such as land cover. But as biodiversity is closely linked with ecosystem functions, variables describing different dimensions of biodiversity should provide essential information to predict and map services produced by these functions. One persistent problem is that most of the organisms primarily responsible for services are invertebrates that suffer from data shortfalls. For example, we still lack estimates of ranges and aggregate biodiversity patterns for most described insect species. But perhaps more importantly, we are missing information on insect functional diversity, or the variation in species’ functional traits, which is most closely linked with the provision of services. The proliferation of open biodiversity data and development of robust modeling methods now make it possible to predict and map species’ distributions even for those with limited data, but the mapping of insect biodiversity patterns is just getting underway. Here, we mapped taxonomic and functional diversity for bumblebees at the country scale for Japan to assess pollination service potential. Specifically, we used citizen science data on bumblebee occurrences and species distribution models to predict bumblebee richness patterns for Japan, then used multivariate trait data to model the functional hypervolumes of bumblebee communities, and finally mapped these values to compare them with richness. We also ran extinction simulations to map functional resilience, or the ability of communities to retain functional diversity after the loss of resident species. Results showed congruences between taxonomic and functional diversity in the central Japanese Alps, also the most resilient region, but mismatch for Hokkaido in Japan’s far north with high richness yet low functional diversity. Such maps can show how dimensions of insect biodiversity differ over space and can lead to different conservation actions depending on whether species or functions are prioritized. An important next step is to integrate these results with ecosystem service models that link functional diversity estimates with actual service provision.

AimGiant clams are iconic bivalves known to serve numerous ecological roles contributing to the functioning of coral reef ecosystems. In the next decade, giant clams will continue to face critical anthropogenic pressures from over‐exploitation for their meat and shells, the aquarium trade and global warming that threaten the persistence of their species. Here, we assess the relationships between different biodiversity components to inform conservation prioritization and management.LocationIndo‐Pacific marine realm.MethodsWe quantified taxonomic, functional and phylogenetic diversity measures throughout 25 marine provinces and assessed their relationships for all 12 giant clam species in the subfamily Tridacninae. These biodiversity measures were used to identify potentially threatened species that contribute disproportionately to trait and evolutionary diversity and to highlight areas for global conservation prioritization of giant clam species.ResultsAnalyses show positive correlations among species richness (SR), functional diversity (FD) and phylogenetic diversity (PD), with the strongest relationship between FD and PD. However, spatial patterns of higher‐than‐expected FD and PD are incongruent with SR patterns, indicating that SR omits information associated with functional and phylogenetic diversity. Among the giant clam species, Tridacna gigas and Hippopus spp. have the greatest functional and evolutionary diversity contributions within assemblies, respectively. Spatial analyses reveal that the Bay of Bengal, Andaman and numerous parts of the eastern Indo‐Pacific potentially hold higher‐than‐expected FD and PD levels relative to their SR and thus warrant more attention with respect to conserving the diversity of giant clams.ConclusionsOur findings underscore the importance of integrating functional trait contributions and evolutionary diversity into conservation planning to better differentiate giant clam assemblages, as it remains challenging to implement dedicated conservation given the limited resources. This study provides comprehensive biodiversity information for managers to initiate measures that holistically capture species' ecological and evolutionary standings across global reef ecosystems.

Gallery forests are important to the maintenance of a substantial portion of the biodiversity in neotropical savanna regions, but management guidelines specific to this forest type are limited. Here, we use birds as study group to assess if: (1) functional traits can predict the abundance and occupancy of forest species within a savanna landscape, (2) habitat structures influence the taxonomic, functional, and phylogenetic diversity of forest assemblages, and (3) less diverse gallery forest assemblages are a nested subset of more diverse assemblages living near continuous forests. Then, we propose strategies on how gallery forests can be managed to maintain their species assemblages amidst the fast expansion of human activities across tropical savanna landscapes. We studied 26 sites of gallery forests in an Amazonian savanna landscape and found that: (1) habitat specificity is the only functional trait that predicts species abundance and occupancy across a landscape; (2) phylogenetic diversity is negatively correlated with understory foliage density; (3) the percentage of forests and savannas around sites is positively correlated with both phylogenetic and functional diversity; (4) increasing human activities around gallery forest negatively influences taxonomic and functional diversity; and (5) forest bird assemblages are not distributed at random across the landscape but show a nested pattern caused by selective colonization mediated by habitat filtering. Our combined findings have three implications for the design of conservation strategies for gallery forest bird assemblages. First, maintaining the connectivity between gallery forests and adjacent continuous forests is essential because gallery forest bird assemblages are derived from continuous forest species assemblages. Second, because most species use the savanna matrix to move across the landscape, effectively managing the savanna matrices where gallery forests are embedded is as important to maintaining viable populations of forest bird species as managing the gallery forest themselves. Third, in savanna landscapes planned to be used for agriculture production, protecting gallery forests alone is not enough. Instead, gallery forests should be protected with surrounding savanna buffers to avoid the detrimental effects (edge effects and isolation) of human activities on their biodiversity.

How much matching there is in functional, phylogenetic and taxonomic optima of epiphytic macrolichen communities along a European climatic gradient?

AimTo explore the impact of island area and isolation on multiple dimensions of ant biodiversity (taxonomic, phylogenetic and functional diversity) and the underlying processes of community assembly on islands.LocationThousand Island Lake, Zhejiang, China, created by dam construction in 1959.TaxonAnts.MethodsWe sampled ants on 33 islands, built a species‐level phylogenetic tree and measured five morphological traits of all species collected to estimate taxonomic, phylogenetic and functional diversity. We used multiple linear regression models and null models to examine the relationships between diversity metrics and island variables (area and isolation).ResultsWe recorded 97 ant species on the study islands. We verified positive diversity–area relationships for species richness, phylogenetic diversity and functional diversity. However, although functional and phylogenetic community structure were indistinguishable from random communities, phylogenetic structure tended to be clustered, whereas functional structure tended to be overdispersed. Additionally, we found the structure of ant communities shifted from phylogenetic and functional clustering on smaller islands to phylogenetic and functional overdispersion on larger islands.Main conclusionsOur results support the hypothesis that environmental filtering is the dominant process structuring ant communities on smaller islands, and that competitive exclusion becomes more important on larger islands. Thus, island area acts as an important filter even though ant community structure on the study islands was indistinguishable from random communities. Moreover, our results show that environmental filtering influences phylogenetic community structure of ants, whereas competitive exclusion influences functional community structure of ants. These findings highlight the need to examine both phylogenetic and functional diversity in order to understand the mechanisms that govern the assembly of natural communities on islands.

Understanding the mechanisms that influence the assembly of natural communities has become a central issue in ecological studies, especially because of the influence of diversity on ecosystem functioning. These mechanisms may be related to niche and neutral processes. Niche-related processes include selection imposed by the abiotic environment and biotic interactions, whereas neutral effects are related to chance or historical events. Mountain ecosystems are among the most suitable models for unraveling the interactions between the facets of biodiversity. The overall aim of this project was to understand the assembly processes of alpine and forest plant communities through phylogenetic and functional diversity across altitudinal gradients in tropical mountains. To respond to this approach, we selected areas from several tropical mountains worldwide. We used lists with altitude records from three tropical montane mountains of tropical ecosystems: Mount Puracé, Colombia; Mount Kilimanjaro, Tanzania; and Mount Haleakalā, Hawaii, USA (CAP. 1). In addition, six sampling sites were established along an elevation gradient of (3200-4100 m). At each station, 10 plots measuring 2.5 m x 4 m were established (CAP. 2 and 3). In addition, 28 isolated individuals of Espeletia lopezii (Asteraceae) were selected; a 70 cm diameter metal ring was centered on each caulescent rosette. In addition, 28 rings were established in the open areas (control) (CAP. 4). The alpha taxonomic diversity was estimated using Hill's numbers (q=0, q=1, q=2) (CAP. 2 and 4). For phylogenetic diversity, six phylogenetic metrics were calculated: lineage diversity as the total length of the phylogenetic branch (PD), mean pairwise phylogenetic distance (MPD), mean nearest taxon phylogenetic distance (MNTD), and standardized effect size of these metrics (CAP. 1, 2 and 4). To determine the functional responses that drive the assembly of communities along the elevation gradient, five functional traits were measured: leaf area, leaf length, leaf thickness, leaf dry matter content, and maximum plant height. The weighted community mean (CWM) of the traits and functional diversity (FD) were estimated (CAP. 3). Different statistical models were used to test the main effects of altitude and soil depth on taxonomic, phylogenetic, and functional metrics. In the three tropical mountains, an environmental filtering effect was observed with increasing altitude, causing phylogenetic clustering, decreasing phylogenetic diversity, and decreasing species richness. The decreasing phylogenetic distances between close relatives are congruent with neo-endemism, suggesting recent diversification of plants at high altitudes in tropical mountains, possibly driven by geographical isolation and environmental heterogeneity (CAP. 1). In Chapter 2, the results showed that as soil depth decreased and altitude increased, páramo plant communities showed a general pattern of decreasing phylogenetic diversity. These results are consistent with the general expectation that community assemblage attributes become more closely related as stressful environmental conditions increase along a gradient. In Chapter 3, the results showed that several functional traits (CWM) and several indices of functional diversity varied significantly along the altitude and soil gradient in the area. Three of the five functional traits showed the potential to describe how the functional composition of páramo communities responded to increasing environmental severity along these environmental gradients. The two functional diversity indices, FDis and FRic, significantly decreased with increasing elevation and decreasing soil depth. In Chapter 4, the vegetation under the canopy of the facilitator plants (E. lopezii) was found to have a positive impact on taxonomic diversity, compared to the control areas. Regarding phylogenetic diversity, the dominant pattern observed was mainly random. These results suggest that, at these altitudes, the metacommunity is strongly filtered by climatic and edaphic factors, and despite the benefits of the facilitation exerted by stem rosettes, it is difficult to detect a pattern of phylogenetic overdispersion. In Chapter 5, as a general trend, a greater number of species were found in locations at higher altitudes, decreasing in locations at lower altitudes, and where climatic seasonality is more marked and filters out species from lineages that are less tolerant to stressful environments. Nitrogen-fixing Fabaceae species were prominent among the important species, especially at low altitudes and more stressful sites. Keywords: Tropical mountains, altitudinal gradient, phylogenetic diversity, functional diversity, plant-plant interaction, community assembly.

From town to town: Predicting the taxonomic, functional and phylogenetic diversity of birds using NDVI

The emergence of metacommunity theory has significantly contributed to our understanding of the drivers of community assembly and biome variation. The Network Location Hypothesis (NPH) posits that tributary communities situated at the source regions of a river are disproportionately susceptible to environmental filtering due to their remote location and consequent reduced connectivity to downstream reaches of the river system. However, downstream communities located in central parts of the river network exhibit increased connectivity to other communities, thereby making them more susceptible to spatial effects. Nonetheless, empirical studies testing this theory have been relatively scarce to date. Additionally, it is widely acknowledged that integrating multiple dimensions of beta diversity can enhance our understanding of the mechanisms driving community assembly. Based on the above, we collected macroinvertebrate samples from a boreal river in China to verify these views. Specifically, we examined the significance of network location on metacommunity assembly (NPH hypothesis) by utilizing a distance-decay relationship and simultaneously assessing multiple dimensions of ecological drivers of beta diversity. Our results revealed that the predictions of the NPH hypothesis were not supported in the study area, with the impact of environmental filtering on community assembly being prevalent regardless of network location. Taxonomic beta diversity consists almost entirely of turnover, with turnover contributing more to functional beta diversity than nestedness, while phylogenetic beta diversity consists of a combination of turnover and nestedness. We observed that a uniform species composition across sites led to higher taxonomic beta diversity in the study area. However, functional redundancy and the presence of closely related species across sites resulted in lower functional and phylogenetic beta diversity compared to taxonomic beta diversity. Although we found some correlation between phylogenetic and functional beta diversity, their mechanisms of variation were not consistent, with phylogenetic beta diversity showing greater variability than functional beta diversity. This suggests that differences in functional traits may be primarily driven by more distantly related species. Therefore, our findings do not fully support the use of phylogenetic distance as a surrogate for functional distance. The present study emphasizes the significance of incorporating multiple dimensions of beta diversity in metacommunity research, as they offer unique insights into beta diversity. Specifically, we found that environmental factors play a crucial role in shaping macroinvertebrate community composition and functional traits, which is associated with the higher environmental heterogeneity within the study area. In contrast, spatial processes, such as dispersal limitations, lead to variations in the evolutionary history of organisms across different locations, which is associated with the larger geographical extent of the study area.

Aim To test how far can macroecological hypotheses relating diversity to environmental factors be extrapolated to functional and phylogenetic diversities, i.e. to the extent to which functional traits and evolutionary backgrounds vary among species in a community or region. We use a spatial partitioning of diversity where regional or γ-diversity is calculated by aggregating information on local communities, local or α-diversity corresponds to diversity in one locality, and turnover or β-diversity corresponds to the average turnover between localities and the region. Location France. Methods We used the Rao quadratic entropy decomposition of diversity to calculate local, regional and turnover diversity for each of three diversity facets (taxonomic, phylogenetic and functional) in breeding bird communities of France. Spatial autoregressive models and partial regression analyses were used to analyse the relationships between each diversity facet and environmental gradients (climate and land use). Results Changes in γ-diversity are driven by changes in both α- and β-diversity. Low levels of human impact generally favour all three facets of regional diversity and heterogeneous landscapes usually harbour higher β-diversity in the three facets of diversity, although functional and phylogenetic turnover show some relationships in the opposite direction. Spatial and environmental factors explain a large percentage of the variation in the three diversity facets (>60%), and this is especially true for phylogenetic diversity. In all cases, spatial structure plays a preponderant role in explaining diversity gradients, suggesting an important role for dispersal limitations in structuring diversity at different spatial scales. Main conclusions Our results generally support the idea that hypotheses that have previously been applied to taxonomic diversity, both at local and regional scales, can be extended to phylogenetic and functional diversity. Specifically, changes in regional diversity are the result of changes in both local and turnover diversity, some environmental conditions such as human development have a great impact on diversity levels, and heterogeneous landscapes tend to have higher diversity levels. Interestingly, differences between diversity facets could potentially provide further insights into how large- and small-scale ecological processes interact at the onset of macroecological patterns.

ISSN 1948‐6596 news and update update Beyond taxonomical space: large‐scale ecology meets func‐ tional and phylogenetic diversity Community ecology traditionally focuses on hypo‐ thetical‐deductive and experimental approaches and often is criticized for narrowing our under‐ standing of nature to local idiosyncrasies, ignoring the importance of historical explanations. On the other hand, approaches taken by macroecologists and biogeographers have been excessively ex‐ ploratory and correlative, with limited success in elucidating the mechanisms responsible for many of the large‐scale patterns we observe in nature (see Gaston & Blackburn 1999, Ricklefs 2008 and references therein). Recognizing that both ap‐ proaches can learn from each other is pivotal in the challenge of integrating data from different scales in order to unravel the ecological and evo‐ lutionary mechanisms that influence current pat‐ terns in biodiversity and ecosystem functioning. Species richness has been the most com‐ mon metric used to represent all aspects of bio‐ logical diversity (from genetic and taxonomic to phenetic diversity). However, species richness alone cannot describe the processes involved in species coexistence and ecosystem functioning and also does not describe properly the differ‐ ences in community structure. In contrast, phy‐ logenetic and functional diversities allow us to understand the relative importance of species composition in terms of evolutionary history and ecological similarities. Phylogenetic diversity (PD) is a biodiversity measure that accounts for the phylogenetic relationship (hence evolutionary his‐ tory) among species, whereas functional diversity (FD) represents how species are distributed in a multidimensional niche space defined by ecologi‐ cal traits. Phylogenetic and functional approaches to community ecology emerged as prominent fields of research in the last decade (Fig. 1), but some‐ how independently and without much crossover in the first years. Early PD measures were pro‐ posed as a tool to select conservation areas, but later the idea was extended to understand how communities are assembled from a regional pool. FD, which initially was considered the holy grail of the biodiversity‐ecosystem functioning agenda, also was rapidly applied as a metric for investigat‐ ing assembly rules (see Pavoine & Bonsall 2011). How could macroecology and biogeography bene‐ fit from these two approaches? The answer lies in understanding what FD and PD should represent and how they relate to each other: while phyloge‐ netic community ecology links evolutionary and biogeographic history to present‐day ecology, functional diversity (as any trait‐based approach) links niche theory to large‐scale approaches, such as macroecology, biogeography or phylogeogra‐ phy. Therefore, combining ecological and phyloge‐ netic frameworks to explain large scale patterns of biodiversity is an important step, taken recently. Large‐scale studies involving PD and FD seems to be increasing at similar rates (Fig.1). Recently, it was shown that both measures can be decom‐ posed into gamma (regional), alpha (local) and beta (turnover) components. Whereas large‐scale studies and any‐scale studies follows a similar trend for beta‐PD, there were few studies with beta‐FD (none at large‐scale). This is perhaps be‐ cause biogeographers and macroecologists were more aware of evolutionary and historical hy‐ potheses, so the conceptual framework of beta‐ PD was likely to be absorbed first. Also, this could reflect the assumption that closely related species should be ecologically more similar than distant related species and, thus, PD should be a good surrogate for FD (in fact this is what most large and local‐scale PD studies used to assume). This traditional assumption is now debated (e.g. Losos 2008), and these two measures may be viewed as complementary, rather than competing, ap‐ proaches (Gomez et al. 2010, Diniz‐Filho et al. 2011, Meynard et al. 2011, Pavoine & Bonsall 2011, Safi et al. 2011). While some large‐scale studies involving PD and FD are exploratory (e.g. Meynard et al. 2011) others have presented hypotheses and predic‐ tions. Safi et al. (2011) investigated global pat‐ frontiers of biogeography 3.3, 2011 — © 2011 the authors; journal compilation © 2011 The International Biogeography Society

Ecosystems with forest and grassland patches as alternative stable states usually contain various closed, semi‐open and open habitats, which may be aligned along a vegetation cover gradient. Taxonomic diversity usually peaks near the middle of the gradient, but our knowledge on functional and phylogenetic diversity trends along gradients is more limited. We investigated the eight main habitats of Hungarian forest‐grassland mosaics, representing various vegetation cover values, and compared their species composition as well as their taxonomic, functional and phylogenetic diversity. We found a compositional gradient ranging from large forest patches through smaller‐sized forest patches and edges to closed and open grasslands. Species richness peaked at the middle of the gradient (at edges). Shannon diversity was high near the middle and at the open end of the gradient. Functional diversity was high throughout woody habitats (in forests and at edges) and was significantly lower in grasslands. When considering all species, phylogenetic diversity tended to peak at north‐facing forest edges. When excluding non‐angiosperms, this peak disappeared. The high taxonomic diversity at the middle of the gradient is in line with the edge‐effect theory. Our results suggest that community assembly in grasslands may be dominated by environmental filtering, while competition may be decisive in woody habitats. The low phylogenetic diversity of grassland habitats can be explained by their young evolutionary age compared to forests. Synthesis. Functional and phylogenetic diversity do not necessarily coincide with taxonomic diversity along vegetation cover gradients. In ecosystems where forest and grassland patches represent alternative stable states, the trends of taxonomic diversity may be similar to those revealed here, but functional diversity patterns may be more system‐specific for some traits. Trends in phylogenetic diversity may vary according to the evolutionary age of the habitats.