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Plum, K.

Publications and source records attributed to Plum, K..

2 recordsLinked to original sources

Temperature stress disrupts reciprocal adaptation in a microbial predator-prey system

Antagonist interactions, such as predator-prey interactions, are widespread in nature and drive both ecological and evolutionary outcomes. Coevolutionary outcomes of antagonistic interactions have been shown to be influenced by environmental conditions, yet the role of abiotic stress in modifying these outcomes remains insufficiently understood. Here we explored how the addition of temperature stress altered evolutionary trajectories of traits of both species in the Pseudomonas fluorescens - Tetrahymena pyriformis (bacteria-ciliate) predator prey system. We found that temperature stress impeded the evolution of traits important for antagonistic interactions in both species. Prey defense levels as well as predators ability to eat prey were limited under temperature stress. We also found that the addition of temperature stress altered growth rate evolution in evolving populations of both species. Taken together, our results show that temperature stress not only alters the evolutionary trajectories of both predator and prey traits but also hinders their coevolution. These findings suggest that environmental stressors may weaken reciprocal coevolution which could have important consequences for the stability and persistence of ecological communities.

evolutionary biology↗

Rapid Adaptation to Road Salts in a Freshwater Microbial Eukaryote

Humans are changing habitat for wildlife in myriad ways and for populations to persist, they must adapt to this change. In parts of the world that experience snow and ice, road salts are often used to make driving safer in the winter. Runoff from these roads increases the salinity in nearby bodies of water, which has been shown to have detrimental physiological and ecological effects in freshwater ecosystems; however, the evolutionary consequences of salinization remain unclear. Tetrahymena are microbial eukaryotes that live in freshwater habitats and serve as an important link in the microbial food loop. In this study, we test how T. thermophila can evolve in response to increasing concentrations of road salts in their environment. Using experimental evolution, we found that T. thermophila adapt quickly to survive and grow better in increasing salinity. However, populations adapted to the highest salt concentrations experience fitness tradeoffs in salt-free environments. These results demonstrate the rapidity with which microbial populations can respond to anthropogenic changes to their environment, yet highlight the potential costs associated with this adaptation.

evolutionary biology↗