Trait Conservatism Research Articles

Strong conservatism in leaf anatomical traits and their multidimensional relationships with leaf economic traits in grasslands under different stressful environments

BackgroundPlant traits and plant adaptive strategies have been affected by the increasing intensity and severity of environmental changes. Given the uncertainty surrounding future environmental conditions, investigating plant trait variations under various stresses is crucial for unraveling plant survival strategies. Leaf anatomical traits are closely responsible for plants’ photosynthesis, respiration and transpiration. However, knowledge of how the multi-species leaf anatomical traits varied in extremely and moderately stressful environments is limited. Our objective was to compare the variation of leaf anatomic traits and adaptation strategies in two different stressful regions of the Qinghai-Tibet Plateau (TP) and Mongolian Plateau (MP) of China.MethodsWe sampled ten sites in each of the two regions (MP and TP) along an environmental gradient. Seven leaf anatomical traits and two leaf economic traits were measured for all leaf samples. Leaf anatomical traits include the traits related to leaf physiological processes (mesophyll thickness (MT), palisade tissue thickness (PT), spongy tissue thickness (ST), palisade-spongy tissue thickness ratio (PST) and epidermal thickness (ET)) and the traits related to trait construction investment (epiderm-leaf thickness ratio (ET/LT) and mesophyll-leaf thickness ratio (MT/LT)). Leaf economic traits include specific leaf area (SLA) and leaf nitrogen content (LN).ResultsThe results revealed that leaf anatomical traits in the TP exhibited greater phylogenetic conservation with thicker structures, being less susceptible to environmental impacts than those in the MP. Additionally, the leaf anatomical and economic traits decoupled both in the MP and TP.ConclusionThese findings highlight that plants adopt diverse strategies to cope with extremely and moderately environmental stresses, but multidimensional trait patterns are generally favored in stressful environments.

A highly resolved nuclear phylogeny uncovers strong phylogenetic conservatism and correlated evolution of fruit color and size in Solanum L.

Mutualisms between plants and fruit-eating animals were key to the radiation of angiosperms. Still, phylogenetic uncertainties limit our understanding of fleshy-fruit evolution, as in the case of Solanum, a genus with remarkable fleshy-fruit diversity, but with unresolved phylogenetic relationships. We used 1786 nuclear genes from 247 species, including 122 newly generated transcriptomes/genomes, to reconstruct the Solanum phylogeny and examine the tempo and mode of the evolution of fruit color and size. Our analysis resolved the backbone phylogeny of Solanum, providing high support for its clades. Our results pushed back the origin of Solanum to 53.1 million years ago (Ma), with most major clades diverging between 35 and 27 Ma. Evolution of Solanum fruit color and size revealed high levels of trait conservatism, where medium-sized berries that remain green when ripe are the likely ancestral form. Our analyses revealed that fruit size and color are evolutionary correlated, where dull-colored fruits are two times larger than black/purple and red fruits. We conclude that the strong phylogenetic conservatism shown in the color and size of Solanum fruits could limit the influences of fruit-eating animals on fleshy-fruit evolution. Our findings highlight the importance of phylogenetic constraints on the diversification of fleshy-fruit functional traits.

Phylogenetic conservatism and coordination in traits of Chinese woody endemic flora

Phylogenetic conservatism and coordination in traits of Chinese woody endemic flora

Environmental colour pattern variation in Mediterranean Podarcis

BackgroundLizards of the genus Podarcis are widespread in the Mediterranean region, including islands and island archipelagos. These small-bodied lizards have a predominantly protective green-brown colouration. However, some populations display unusual patterns, in which the colouration is predominantly blue or uniformly black. This study explores the factors that influence this chromatic variation, whether environmental (climate and island conditions) or evolutionary (phylogenetic trait conservatism). The colouration of 1400 individuals (27 species) was analysed in the CIELAB colour space.ResultsPagel’s λ indicated that colouration is weakly conserved within phylogenetic lineages. Although the island surface plays a key role in the chromatic variability of these lacertids, geographic isolation and climate hold less influence. The colouration of some small island populations tends to be uniform and dark, possibly due to intense intraspecific competition and lower predatory pressure.ConclusionsThis study highlights the importance of island populations in understanding the processes that favour the emergence of extreme phenotypes in small ectothermic vertebrates.

Phylogeny and climate explain contrasting hydraulic traits in different life forms of 150 woody Fabaceae species

Abstract The contrasting hydraulic traits observed among different plant life forms are shaped by entangled environmental and evolutionary processes. However, we lack understanding of the relative importance of life form, climate and phylogeny in explaining the variance of hydraulic traits. We analysed seven hydraulic traits and eleven climatic variables of 150 Fabaceae species representing three life forms from 62 sites worldwide, using phylogenetic comparative analyses and variance partitioning. The phylogenetic signal found in most traits disappeared after considering life form, indicating that phylogenetic conservatism in traits originated from the divergence among life forms. The trait‐climate relationships were also phylogenetically dependent, implying that trait responses are driven by climate and phylogeny together. Variance partitioning showed that phylogeny and climate explained greater trait variation than life form did. Synthesis. The climate‐driven hydraulic trait responses in Fabaceae still existed with phylogeny being considered, suggesting that this large family may be particularly sensitive to climate change. Our results emphasise the need to include phylogeny in plant hydraulic adaptation studies under future climate change.

Soil deterioration due to long-term grazing of desert-steppe promotes stress-tolerant ecological strategies in plants

Predicting the impact of grazing on desert steppes' vegetation is crucial for sustainable management. The competitor, stress-tolerator and ruderal (CSR) theory has offer valuable insights into plant adaptive capacity and predicting changes in vegetation structure. However, whether adaptive strategy of desert steppe change with grazing intensity is not understood yet. We conducted a comprehensive assessment of the effects of 19 years of varying grazing intensities (no grazing: CK; light grazing: LG; moderate grazing: MG; heavy grazing: HG) on plant CSR strategies. Within the desert steppe ecosystem, the prevailing plant community strategy leaned towards SR (Stress-tolerant/Ruderal) under non-grazed conditions (C:S:R = 2:48:50 %). However, as grazing intensity increased, the S-score increased significantly from 48 % to 62 % while the R-score decreased from 50 % to 36 %. This trend persisted across functional groups and species, except for shrubs, due to the convergent response of traits and ecological strategies of these species under intense grazing pressure. Furthermore, our findings reveal that the shift of CSR on the community level was primarily influenced by soil nutrients and soil density, but not by evolutionary history (phylogenetic conservatism of traits). This suggests that plant traits co-evolved under prolonged environmental stress, resulting consistent variation and ecological strategies in desert grasslands. Overall, long-term grazing reinforced selective pressure, creating a simplified plant community structure with low levels of diversity and productivity, dominated by conservative resource-use strategy. This study highlights the mechanisms of plant adaptation to the prolonged grazing disturbance in desert steppes.

Phylogenetic diversity and community wide-trait means offer different insights into mechanisms regulating aboveground carbon storage

Both attributes of functional traits and phylogenetic diversity influence ecosystem functions, but which of these factors is most important is still poorly understood in natural systems. Using data from West African forests and tree savannas, we analyse how (i) phylogenetic diversity complements attributes of functional traits in explaining aboveground carbon (AGC); (ii) phylogenetic diversity relates with attributes of functional traits along gradients of phylogenetic signal; and (iii) pathways between phylogenetic diversity and attributes of functional traits relate AGC to soil and climate. Phylogenetic diversity was measured as standardised effect size of Mean Pairwise Distance (sesMPD) and Mean Nearest Taxon Distance (sesMNTD). Functional dispersion (FDis) and community weighted mean (CWM) were calculated for four traits related to leaf economics spectrum and plant life-history.Functional traits-based models explained 11 % of AGC variability. With two out of the four traits being phylogenetically conserved, incorporating phylogenetic diversity in the models increased the explained variance in AGC by 15 %. The slope of phylogenetic diversity-trait relationship was more responsive to trait conservatism for FDis than CWM. AGC was positively influenced by sesMPD and CWM of plant maximum height. In turn, CWM of plant maximum height increased with higher soil nitrogen and climate moisture, whereas sesMPD was negatively related with climate moisture. Although FDis was positively associated with sesMPD, it was not as important as sesMPD and CWM of plant maximum height in influencing and relating AGC to soil nitrogen and climate moisture.Our results suggest that phylogenetic diversity is important for AGC but does not fully reflect the functional mechanisms pertaining to community-wide trait means. The study also demonstrates the role of environment in regulating AGC, which operates through differences in community fitness driven by tall plant stature, and evolutionary processes whereby closely related species are maintained in less arid environments.

Discordant spatiotemporal dynamics of functional and phylogenetic diversity of rotiferan communities exposed to aquaculture effluent.

The growth of the human population brought about the global intensification of aquacultural production, and aquaculture became the fastest growing animal husbandry sector. Effluent from aquaculture is an anthropogenic environmental burden, containing organic matter, nutrients and suspended solids that affect water quality especially in the water bodies of high biodiversity and conservation value. Water quality assessment often relies on bioindicators, analysing changes in taxonomic diversity of various freshwater organismal groups. Stepping beyond taxon diversity, we used functional and phylogenetic diversities of rotifers to identify factors affecting their community organization in response to an aquaculture effluent gradient in the largest oxbow lake in the Carpathian Basin, Hungary. Sampling was carried out three times per season at five points along a 3.5 km section of the oxbow lake, including the point of effluent inflow. We used eight traits to evaluate functional diversity: body size, trophi type, feeding mode, protection type, body wall type, corona type, habitat preference and tolerance level. Functional and phylogenetic distances among the 24 species identified indicated trait conservatism. Rotiferan diversity increased with increasing distance from the point of influx in spring and summer. Among the factors affecting community organization in spring and summer, we find examples of environmental filtering, while in autumn the role of biotic interaction is more frequent. Under nutrient-rich conditions in spring and summer, organisms belonging to the same functional group were dominant, whereas under oligotrophic conditions, more diverse but less abundant groups were present. Considering functional and phylogenetic traits allowed us to identify organising forces of rotifer communities in the largest oxbow lake of the Hungarian Lowland.

Species identity and resource availability explain variation among above and below-ground functional traits in Himalayan temperate forests

Trait variation across spatial and temporal scales allows plants to adapt to changing environments. Understanding the mechanisms driving trait variability, it is important to unravel how plant functional traits adapt to changing climates. Plant chemical traits (C, N, P, K, S, Ca, Mg, Mn, Zn, Fe, Cu, and Na) for leaf, stem, and root were studied for ten dominant evergreen tree species along increasing elevation (1500–3000 m asl) for three seasons (summer, monsoon, and winter) in temperate forests of western Himalaya, India. We also collected five soil samples from each plot to analyze chemical trait variation with respective soil nutrient concentrations. Our results suggested that temperature significantly (P < 0.05) affected leaf traits, whereas stem and root traits were maximally driven by light and water availability (P < 0.05). Maximum trait variance was observed at species level (∼48%) followed by individual level (∼45%). Coniferous species displayed strong trait coordination among organs, whereas broad-leaved species showed strong correlation with environmental resources. Trait correlation with respective soil nutrient concentration was found strongest for the root, followed by stem, and ultimately got lost for leaf traits (except Ca, Mg, and Mn). Weaker plant–soil interaction for leaf traits showed external factors such as lopping alter plant-soil relationship. We provide evidence of varying degrees of trait conservatism within broad-leaved and coniferous trees that leads to increased trait variability. We also emphasize the importance of considering major abiotic and biotic stresses exerted on different plant organs when investigating trait variation along environmental gradients.

Species phylogeny, ecology, and root traits as predictors of root exudate composition.

Root traits including root exudates are key factors affecting plant interactions with soil and thus play an important role in determining ecosystem processes. The drivers of their variation, however, remain poorly understood. We determined the relative importance of phylogeny and species ecology in determining root traits and analyzed the extent to which root exudate composition can be predicted by other root traits. We measured different root morphological and biochemical traits (including exudate profiles) of 65 plant species grown in a controlled system. We tested phylogenetic conservatism in traits and disentangled the individual and overlapping effects of phylogeny and species ecology on traits. We also predicted root exudate composition using other root traits. Phylogenetic signal differed greatly among root traits, with the strongest signal in phenol content in plant tissues. Interspecific variation in root traits was partly explained by species ecology, but phylogeny was more important in most cases. Species exudate composition could be partly predicted by specific root length, root dry matter content, root biomass, and root diameter, but a large part of variation remained unexplained. In conclusion, root exudation cannot be easily predicted based on other root traits and more comparative data on root exudation are needed to understand their diversity.

Niche conservatism over deep timescales and diverse niche axes in land vertebrates

AbstractAimThere has been considerable interest in niche conservatism, the idea that ecological variables are similar among related species. Much research has focused on climatic niches of recently diverged species, rather than deeper timescales or non‐climatic niche axes. Furthermore, it has been suggested that conservatism disappears over deeper timescales, and is greater in alpha niche traits (like diet and microhabitat) than beta niche variables (like climate). Here, we test these latter two ideas by comparing patterns of phylogenetic conservatism among 10 niche variables across major clades of land vertebrates.LocationGlobal.Time PeriodPresent to 350 million years ago.Major Taxa StudiedTetrapods, including amphibians, mammals, lepidosaurs (including lizards and snakes), turtles, crocodilians and birds.MethodsThe 10 niche variables included four alpha niche components (diet, diel activity, habitat, body temperature) and six beta niche components (related to climatic temperature and precipitation). We analysed these variables on time‐calibrated phylogenies with similar taxon sampling (~1700 species), using phylogenetic signal (lambda) to estimate conservatism, along with the D statistic and estimates of evolutionary rates.ResultsPhylogenetic signal was generally strong across all variables, with lambda generally &gt;0.80 (with 1.0 representing maximum signal). Nevertheless, mean phylogenetic signal was lower in beta niche traits than alpha niche traits (based on lambda and especially the D statistic), and alpha niche traits showed significantly slower rates of evolution.Main ConclusionsWe address two long‐held views in the literature on niche conservatism, rejecting one but supporting the other. We show that phylogenetic signal does not disappear over deep timescales for many important niche variables, even over 350 million years. We also generally support greater conservatism in alpha niche traits than beta niche traits over hundreds of millions of years, a pattern that was previously suggested (but not explicitly tested) based on closely related species.

Species‐specific functional traits rather than phylogenetic relatedness better predict future range‐shift responses of odonates

Abstract Climate change has the potential to modify habitat characteristics and, consequently, induce species responses to ongoing environmental changes. Functional traits determine both if a species can persist and maintain stable population sizes in particular ecological conditions, and its capacity to disperse to more favourable habitats. Given that functional traits evolve over time, one could expect closely related species to show similar responses to climate change, which should identify vulnerable lineages. Alternatively, species‐specific functional traits may anticipate species responses to climate change, and therefore, trait composition should be a strong predictor. We compiled a comprehensive dataset of functional traits of 84 Iberian and Moroccan odonates species and built a phylogenetic tree to determine if dissimilarity of traits and phylogenetic relatedness are relevant to better discriminate species range‐shift responses to climate change. Modelling results for 66 species showed clear impacts of the increase in temperature and drought events on their potential distribution. The traits that best‐discriminated species that expanded their ranges were multivoltinism, short‐life cycles and preference for temporary habitats, whereas species with a reduced and displaced potential distribution were mostly semivoltine, with a short flying season, oviposition on gravel and restricted to permanent streams, small rivers or oligotrophic lakes. Trait conservatism was rejected and phylogenetic relatedness was a poor predictor of range shifts. Considering odonates as model organisms, traits such as voltinism, beginning and prolongation of flight period and preference of temporal habitats should be examined to anticipate range‐shift responses of freshwater insects to climate change.

Why phylogenetic signal of traits is important in ecosystems: uniformity of a plant trait increases soil fauna, but only in a phylogenetically uniform vegetation

Phylogenetically closely related plant species often share similar trait states (phylogenetic signal), but local assembly may favor dissimilar relatives and thereby decouple the diversity of a trait from the diversity of phylogenetic lineages. Associated fauna might either benefit from plant trait diversity, because it provides them complementary resources, or suffer from it due to dilution of preferred resources. We hence hypothesize that decoupling of trait and phylogenetic diversity weakens the relationship between the plant-trait diversity and the abundance and diversity of associated fauna. Studying permanent meadows, we tested for combined effects of plant phylogenetic diversity and diversity of two functional traits (specific leaf area, leaf dry matter content) on major groups of soil fauna (earthworms, mites, springtails, nematodes). We found that only in phylogenetically uniform plant communities, was uniformity in the functional traits associated with (i) high abundance in springtails, and (ii) high abundance of the sub-group that feeds more directly on plant material (in springtails and mites) or those that are more prone to disturbance (in nematodes), and (iii) high diversity in all three groups tested (springtails, earthworms, nematodes). Our results suggest that soil fauna profits from the resource concentration in local plant communities that are uniform in both functional traits and phylogenetic lineages. Soil fauna would hence benefit from co-occurrence of closely related plants that have conserved the same trait values, rather than of distantly related plants that have converged in traits. This might result in faster decomposition and a positive feedback between trait conservatism and ecosystem functioning.

The role of phylogenetic relatedness on success of non‐native plants crossing the naturalization–invasion transition in North America

Understanding the causes and consequences of biological invasions is a great challenge in ecology and conservation biology. The ability to predict which naturalized species are likely to become invasive would be a great step forward in managing and preventing invasions. The goal of this study is to test whether invasive species are a phylogenetically clustered subset of naturalized species at continental and regional scales, and to compare phylogenetic relatedness of invasive angiosperms with respect to species pools of non‐native naturalized angiosperms in North America. We divided North America into 65 state‐ or province‐level regions, and collated naturalized and invasive species lists of angiosperms for each region. Two phylogenetic metrics (net relatedness index (NRI) and nearest taxon index (NTI)), which represent different evolutionary depths, were used to quantify phylogenetic relatedness of naturalized and invasive angiosperms in North America, with respect to different species pools. We related phylogenetic relatedness of invasive angiosperms to climatic variables. We found that most invasive angiosperm assemblages are a phylogenetically clustered subset of their respective naturalized species pools, and the phylogenetic clustering of invasive species is greater in regions with lower temperature and precipitation. The pattern of phylogenetic clustering of invasive species likely reflects phylogenetic conservatism of traits associated with invasiveness. It may also reflect a tendency towards greater invasiveness for species with novel trait combinations compared to the non‐invasive naturalized species assemblages.

Morphology and niche evolution influence hummingbird speciation rates.

How traits affect speciation is a long-standing question in evolution. We investigate whether speciation rates are affected by the traits themselves or by the rates of their evolution, in hummingbirds, a clade with great variation in speciation rates, morphology and ecological niches. Further, we test two opposing hypotheses, postulating that speciation rates are promoted by trait conservatism or, alternatively, by trait divergence. To address these questions, we analyse morphological (body mass and bill length) and niche traits (temperature and precipitation position and breadth, and mid-elevation), using a variety of methods to estimate speciation rates and correlate them with traits and their evolutionary rates. When it comes to the traits, we find faster speciation in smaller hummingbirds with shorter bills, living at higher elevations and experiencing greater temperature ranges. As for the trait evolutionary rates, we find that speciation increases with rates of divergence in the niche traits, but not in the morphological traits. Together, these results reveal the interplay of mechanisms through which different traits and their evolutionary rates (conservatism or divergence) influence the origination of hummingbird diversity.

A dated phylogeny of the Neotropical Dipterygeae clade reveals 30 million years of winged papilionate floral conservatism in the otherwise florally labile early-branching papilionoid legumes

Abstract The early-branching clades of Fabaceae subfamily Papilionoideae are characterized by their remarkable lability in floral architecture. In contrast, more derived papilionoid lineages are marked by evolutionary conservatism towards strongly bilateral, papilionate flowers. Here, we show an unexpected example of conservatism of a unique floral architecture during the early diversification history of the papilionoids. We built the most comprehensively sampled molecular phylogenetic tree with a focus on the early-diverging papilionoid Dipterygeae clade to evaluate conservatism of the winged papilionate architecture and associated traits related to flower specialization (e.g. zygomorphy, petal differentiation, stable stamen number and stamen sheath). Dipterygeae comprise c. 22 species of mostly giant trees from across tropical forests in Central America and the Amazon, but they are also ecologically dominant in the savannas of the Brazilian Central Plateau. Phylogenetic analyses of nuclear ribosomal ITS/5.8S and plastid matK and trnL intron sequences strongly supported inter-relationships and the monophyly of each genus (Dipteryx, Monopteryx, Pterodon and Taralea). Bayesian relaxed-clock dating and a Bayesian model of ancestral character estimation revealed c. 30 Myr of conservatism of all winged papilionate-related flower traits in a clade comprising the most recent common ancestor of Dipteryx, Pterodon and Taralea, but lability in fruit morphology during the diversification of the entire Dipterygeae clade. Despite Monopteryx and remaining Dipterygeae being florally discrepant, they are collectively defined by a floral synapomorphy that is unique among all papilionoid Fabaceae: the highly differentiated calyx, where the two upper lobes are enlarged and wing-like, whereas the other three lower lobes are reduced. We suggest that the different dispersal strategies and the ancient winged papilionate floral conservatism in Dipterygeae, which has maintained effective ecological interactions with specialized pollinators and ensured the protection of young flower buds and developing fruits, may explain successful evolutionary and ecological persistence of the clade across the main Neotropical biomes.

Drivers of taxonomic, functional and phylogenetic diversities in dominant ground-dwelling arthropods of coastal heathlands.

Although functional and phylogenetic diversities are increasingly used in ecology for a variety of purposes, their relationship remains unclear, and this relationship likely differs among taxa, yet most recent studies focused on plants. We hypothesize that communities may be diverse in functional traits due to presence of: many phylogenetic lineages, trait divergence within lineages, many species and random functional variation among species, weak filtering of traits in favorable environments, or strong trait divergence in unfavorable environments. We tested these predictions for taxa showing higher (ants), or lower (spiders, ground beetles) degrees of competition and niche construction, both of which might decouple functional traits from phylogenetic position or from the environment. Studying > 11,000 individuals and 216 species from coastal heathlands, we estimated functional as minimum spanning trees using traits related to the morphology, feeding habits and dispersal, respectively. Relationships between functional and phylogenetic diversities were overall positive and strong. In ants, this relationship disappeared after accounting for taxonomic diversities and environments, whereas in beetles and spiders taxonomic diversity is related to functional diversity only via increasing phylogenetic diversity. Environmental constraints reduced functional diversity in ants, but affected functional diversity only indirectly via phylogenetic diversity (ground beetles) and taxonomic and then phylogenetic diversity (spiders and ground beetles). Results are consistent with phylogenetic conservatism in traits in spiders and ground beetles. In ants, in contrast, traits appear more phylogenetically neutral with any new species potentially representing a new trait state, tentatively suggesting that competition or niche construction might decouple phylogenetics from trait diversity.

Impact of nitrogen and phosphorus addition on resident soil and root mycobiomes in beech forests

N and P are essential macronutrients for all organisms. How shifts in the availability of N or P affect fungal communities in temperate forests is not well understood. Here, we conducted a factorial P × N fertilization experiment to disentangle the effects of nutrient availability on soil-residing, root-associated, and ectomycorrhizal fungi in beech (Fagus sylvatica) forests differing in P availability. We tested the hypotheses that in P-poor forests, P fertilization leads to enhanced fungal diversity in soil and roots, resulting in enhanced P nutrition of beech, and that N fertilization aggravates P shortages, shifting the fungal communities toward nitrophilic species. In response to fertilizer treatments (1 × 50 kg ha−1 P and 5 × 30 kg ha−1 N within 2 years), the labile P fractions increased in soil and roots, regardless of plant-available P in soil. Root total P decreased in response to N fertilization and root total P increased in response to P addition at the low P site. Ectomycorrhizal species richness was unaffected by fertilizer treatments, but the relative abundances of ectomycorrhizal fungi increased in response to P or N addition. At the taxon level, fungal assemblages were unaffected by fertilizer treatments, but at the order level, different response patterns for saprotrophic fungi among soil and ectomycorrhizal fungi on roots were found. Boletales increased in response to P, and Russulales decreased under N + P addition. Our results suggest that trait conservatism in related species afforded resistance of the resident mycobiome composition to nutritional imbalances.

Phylogenetic conservatism drives nutrient dynamics of coral reef fishes

The relative importance of evolutionary history and ecology for traits that drive ecosystem processes is poorly understood. Consumers are essential drivers of nutrient cycling on coral reefs, and thus ecosystem productivity. We use nine consumer “chemical traits” associated with nutrient cycling, collected from 1,572 individual coral reef fishes (178 species spanning 41 families) in two biogeographic regions, the Caribbean and Polynesia, to quantify the relative importance of phylogenetic history and ecological context as drivers of chemical trait variation on coral reefs. We find: (1) phylogenetic relatedness is the best predictor of all chemical traits, substantially outweighing the importance of ecological factors thought to be key drivers of these traits, (2) phylogenetic conservatism in chemical traits is greater in the Caribbean than Polynesia, where our data suggests that ecological forces have a greater influence on chemical trait variation, and (3) differences in chemical traits between regions can be explained by differences in nutrient limitation associated with the geologic context of our study locations. Our study provides multiple lines of evidence that phylogeny is a critical determinant of contemporary nutrient dynamics on coral reefs. More broadly our findings highlight the utility of evolutionary history to improve prediction in ecosystem ecology.

Looking at the past to infer into the future: Thermal traits track environmental change in Liolaemidae.

The diversity of habitats generated by the Andes uplift resulted a mosaic of heterogeneous environments in South America for species to evolve a variety of ecological and physiological specializations. Species in the lizard family Liolaemidae occupy a myriad of habitats in the Andes. Here, we analyze the tempo and mode of evolution in the thermal biology of liolaemids. We assessed whether there is evidence of local adaptation (lability) or conservatism (stasis) in thermal traits. We tested the hypothesis that abiotic factors (e.g., geography, climate) rather than intrinsic factors (egg-laying [oviparous] or live-bearing [viviparous], substrate affinity) explain variation in field active body temperature (Tb ), preferred temperature (Tp ), hours of restriction of activity, and potential hours of activity. Although most traits exhibited high phylogenetic signal, we found variation in thermal biology was shaped by geography, climate, and ecological diversity. Ancestral character reconstruction showed shifts in Tb tracked environmental change in the past ∼20,000 years. Thermal preference is 3°C higher than Tb , yet exhibited a lower rate of evolution than Tb and air temperature. Viviparous Liolaemus have lower Tb s than oviparous species, whereas Tp is high for both modes of reproduction, a key difference that results in a thermal buffer for viviparous species to cope with global warming. The rapid increase in environmental temperatures expected in the next 50-80 years in combination with anthropogenic loss of habitats are projected to cause extirpations and extinctions in oviparous species.