Prey identity affects fitness of a generalist consumer in a brown food web.

The use of ever-advancing sequencing technologies has revealed incredible biodiversity at the microbial scale, and yet we know little about the ecological interactions in these communities. For example, in the phytotelmic community found in the purple pitcher plant, ecologists typically consider the bacteria as a functionally homogenous group. In this food web, bacteria decompose detritus and are consumed by protozoa that are considered generalist consumers.

Nutrient dynamics in coral symbiosis depend on both the relative and absolute abundance of Symbiodiniaceae species.

Background: Symbionts provide a variety of reproductive, nutritional, and defensive resources to their hosts, but those resources can vary depending on symbiont community composition. As genetic techniques open our eyes to the breadth of symbiont diversity within myriad microbiomes, symbiosis research has begun to consider what ecological mechanisms affect the identity and relative abundance of symbiont species and how this community structure impacts resource exchange among partners. Here, we manipulated the in hospite density and relative ratio of two species of coral endosymbionts (Symbiodinium microadriaticum and Breviolum minutum) and used stable isotope enrichment to trace nutrient exchange with the host, Briareum asbestinum.

Predator dispersal influences predator distribution but not prey diversity in pitcher plant microbial metacommunities.

The spatial distribution of predators can affect both the distribution and diversity of their prey. Therefore, differences in predator dispersal ability that affect their spatial distribution, could also affect prey communities. Here, we use the microbial communities within pitcher plant leaves as a model system to test the relationship between predator (protozoa) dispersal ability and distribution, and its consequences for prey (bacteria) diversity and composition.

Symbiont genotype influences holobiont response to increased temperature.

As coral reefs face warming oceans and increased coral bleaching, a whitening of the coral due to loss of microalgal endosymbionts, the possibility of evolutionary rescue offers some hope for reef persistence. In tightly linked mutualisms, evolutionary rescue may occur through evolution of the host and/or endosymbionts. Many obligate mutualisms are composed of relatively small, fast-growing symbionts with greater potential to evolve on ecologically relevant time scales than their relatively large, slower growing hosts.

Individual variation in growth and physiology of symbionts in response to temperature.

In many cases, understanding species' responses to climate change requires understanding variation among individuals in response to such change. For species with strong symbiotic relationships, such as many coral reef species, genetic variation in symbiont responses to temperature may affect the response to increased ocean temperatures. To assess variation among symbiont genotypes, we examined the population dynamics and physiological responses of genotypes of in response to increased temperature.

Evolutionary responses to global change in species-rich communities.

Evolution in nature occurs in the proverbial tangled bank. The species interactions characterizing this tangled bank can be strongly affected by global change and can also influence the fitness and selective effects of a global change on a focal population. As a result, species interactions can influence which traits will promote adaptation and the magnitude or direction of evolutionary responses to the global change.

Illegal Trade of Wild-Captured Lemur catta within Madagascar.

Lemur catta is the most reported illegal captive lemur. We document 286 L. catta that were held in illegal captive conditions in Madagascar.

Genetic variation in , a coral reef symbiont, in response to temperature and nutrients.

Symbionts within the family are important on coral reefs because they provide significant amounts of carbon to many different reef species. The breakdown of this mutualism that occurs as a result of increasingly warmer ocean temperatures is a major threat to coral reef ecosystems globally. Recombination during sexual reproduction and high rates of somatic mutation can lead to increased genetic variation within symbiont species, which may provide the fuel for natural selection and adaptation.

Pick your trade-offs wisely: Predator-prey eco-evo dynamics are qualitatively different under different trade-offs.

In recent decades, myriad studies have explored the population dynamics of coevolving populations of predator and prey. A variety of choices are made in these models: exponential or logistic prey growth in the absence of a predator, various forms of predator functional response, and uni- or bi-directional trait axes. In addition, some form of trade-offs are assumed in order to prevent run-away evolution of the prey and predator traits.

Genetic variation in mutualistic and antagonistic interactions in an invasive legume.

Mutualists may play an important role in invasion success. The ability to take advantage of novel mutualists or survive and reproduce despite a lack of mutualists may facilitate invasion by those individuals with such traits. Here, we used two greenhouse studies to examine how soil microbial communities in general and mutualistic rhizobia in particular affect the performance of a legume species (Medicago polymorpha) that has invaded five continents.

Evolution of increased Medicaco polymorpha size during invasion does not result in increased competitive ability.

Species invading new habitats experience novel selection pressures that can lead to rapid evolution, which may contribute to invasion success and/or increased impact on native community members. Many studies have hypothesized that plants in the introduced range will be larger than those in the native range, leading to increases in competitive ability. There is mixed support for evolution of larger sizes in the introduced range, but few studies have explicitly tested whether evolutionary changes result in decreased competitive responses or increased competitive effects on other species in the community.

Testing genotypic variation of an invasive plant species in response to soil disturbance and herbivory.

Herbivores, competitors, and predators can inhibit biological invasions ("biotic resistance" sensu Elton 1959), while disturbance typically promotes biological invasions. Although biotic resistance and disturbance are often considered separately in the invasion literature, these two forces may be linked. One mechanism by which disturbance may facilitate biological invasions is by decreasing the effectiveness of biotic resistance.

A shift from exploitation to interference competition with increasing density affects population and community dynamics.

Intraspecific competition influences population and community dynamics and occurs via two mechanisms. Exploitative competition is an indirect effect that occurs through use of a shared resource and depends on resource availability. Interference competition occurs by obstructing access to a resource and may not depend on resource availability.

Quantifying nonadditive selection caused by indirect ecological effects.

In natural biological communities, species interact with many other species. Multiple species interactions can lead to indirect ecological effects that have important fitness consequences and can cause nonadditive patterns of natural selection. Given that indirect ecological effects are common in nature, nonadditive selection may also be quite common.

Causes and consequences of failed adaptation to biological invasions: the role of ecological constraints.

Biological invasions are a major challenge to native communities and have the potential to exert strong selection on native populations. As a result, native taxa may adapt to the presence of invaders through increased competitive ability, increased antipredator defences or altered morphologies that may limit encounters with toxic prey. Yet, in some cases, species may fail to adapt to biological invasions.

Rethinking niche evolution: experiments with natural communities of Protozoa in pitcher plants.

Classic niche theory predicts that competing species will evolve to use different resources and interact less, whereas recent niche-converge ideas predict that species evolve to use similar resources and interact more. Most data supporting niche evolution are based on observations of contemporary niche use, whereas experimental support is quite sparse. We followed the evolution of four species of Protozoa during succession in the water-filled leaves of the pitcher plant, Sarracenia purpurea, and found that evolution in multispecies systems follows a surprising pattern.

The relative importance of rapid evolution for plant-microbe interactions depends on ecological context.

Evolution can occur on ecological time-scales, affecting community and ecosystem processes. However, the importance of evolutionary change relative to ecological processes remains largely unknown. Here, we analyse data from a long-term experiment in which we allowed plant populations to evolve for three generations in dry or wet soils and used a reciprocal transplant to compare the ecological effect of drought and the effect of plant evolutionary responses to drought on soil microbial communities and nutrient availability.

Testing successional hypotheses of stability, heterogeneity, and diversity in pitcher-plant inquiline communities.

Succession is a foundation concept in ecology that describes changes in species composition through time, yet many successional patterns have not been thoroughly investigated. We highlight three hypotheses about succession that are often not clearly stated or tested: (1) individual communities become more stable over time, (2) replicate communities become more similar over time, and (3) diversity peaks at mid-succession. Testing general patterns of succession requires estimates of variation in trajectories within and among replicate communities.

Evolution in response to direct and indirect ecological effects in pitcher plant inquiline communities.

Ecologists have long recognized the importance of indirect ecological effects on species abundances, coexistence, and diversity. However, the evolutionary consequences of indirect interactions are rarely considered. Here I conduct selection experiments and examine the evolutionary response of Colpoda sp.

Evolution of prey in ecological time reduces the effect size of predators in experimental microcosms.

Ecologists have long studied the effect of predators on prey population abundance while evolutionary biologists have measured prey trait evolution in response to predation. Ecological and evolutionary processes were generally thought to occur on different time scales, but recent evidence suggests that evolution may alter the ecological effects of predation over the course of ecological experiments. We used a protozoan and its mosquito-larvae predator, naturally found in the water-filled leaves of pitcher plants, to examine the effect of prey evolution on predator-prey interactions.

Beyond the Patch: Disturbance Affects Species Abundances in the surrounding Community.

The role of disturbance in community ecology has been studied extensively and is thought to free resources and reset successional sequences at the local scale and create heterogeneity at the regional scale. Most studies have investigated effects on either the disturbed patch or on the entire community, but have generally ignored any effect of or on the community surrounding disturbed patches. We used marine fouling communities to examine the effect of a surrounding community on species abundance within a disturbed patch and the effect of a disturbance on species abudance in the surrounding community.

The risk of polyspermy in three congeneric sea urchins and its implications for gametic incompatibility and reproductive isolation.

Developmental failure caused by excess sperm (polyspermy) is thought to be an important mechanism driving the evolution of gamete-recognition proteins, reproductive isolation, and speciation in marine organisms. However, these theories assume that there is heritable variation in the susceptibility to polyspermy and that this variation is related to the overall affinity between sperm and eggs. These assumptions have not been critically examined.