BioScience 113

As climate change is set to exceed the current physiological limits of many species, survival in future oceans will depend on the ability to acclimate, adapt, and/or migrate. However, this response may be further complicated by ecological interactions, such as symbioses, where the fate of two or more organisms are tied together. Cnidarians, such as coral and sea anemones, form a mutually beneficial relationship with microscopic algae, but this symbiosis breaks down under high temperature.

The flora and fauna on this planet are currently facing unprecedented environmental change. In response, species can go extinct, adapt, or move where they live. Species in the ocean are moving in response to recent anthropogenic impacts at a rate 6x faster than species in terrestrial ecosystems. However, there is immense variability around this average. Species vary in movement to new locations based on population size, traits such as reproductive strategy and mobility, and where they are living.

Among the many constituents of a plant’s environment, water is critical to the functionality of most of a plant’s physiological processes. Therefore, it is imperative to clarify how plants acquire, retain, utilize, and lose water to understand how these organisms will perform in a changing environment. The most salient metrics of plant responses to drought at leaf scale are pressure volume (PV) curve traits, estimated from the relationship between leaf water potential (Ψleaf), a common measurement of water stress, and relative water content (RWC).

The study of kinematics explicitly integrates the morphologies that organisms possess with motions they generate and is vital to our understanding of the evolution of functional systems. Traditional methods have primarily focused on detailed comparisons of relatively few taxa. I will discuss my recent work on an approach for evaluating complex biological motions in a manner amenable to both single species analysis and broad comparative study of kinematic diversity.

The sun is the ultimate source of energy for almost all forms of life on Earth, with about half of global primary productivity occurring in marine systems. While chlorophyll-based photosystems have been studied since the 19th century, the presence of rhodopsin (retinal-based) light harvesting complexes in marine environments was not known until the year 2000. Microbial rhodopsins are simple light-driven ion-pumps present in greater than 80% of the bacteria in the ocean’s photic zone and appear in all three domains of microbial life.

Insect interactions with host plants and other organisms provide unique and powerful models for understanding the evolutionary ecology of species interactions and molecular responses to stressors including host plant toxins, pathogens, and pesticides. I will present work investigating 1) the effects of plant toxins on specialist insect fitness and gene expression, and 2) the interactive effects of evolved pesticide resistance, pesticide exposure, and pathogen infection on insect fitness, immunity, and gene expression.

I will talk about the ecology and genetics behind germination responses to cold in Arabidopsis thaliana and the environmental changes that explain the evolution of the germination niche in this species.

The Hawaiian bobtail squid, Euprymna scolopes, is well known for its light organ association with the bioluminescent bacterium Vibrio fischeri. Female squid also house a bacterial consortium as part of their reproductive system that helps protect developing eggs from pathogens. I'll cover our current research into understanding the function of this defensive symbiosis and how the association is established during development.

Working in Dr. Peyman Golshani's lab at UCLA and nearing the completion of his PhD, Blake Madruga is currently designing, building, and using, novel compact multiphoton microscope systems that can be worn by freely behaving mice to image neural activity as they navigate, intract, and perform tasks. This system addresses the studies that have shown decreased or modified neural activity in mice participating in otherwise unnatural head-fixed or virtual reality based behaviours.

Francesca Mariani is an Associate Professor and Director of the Master's Program in Stem Cell Biology & Regenerative Medicine at Keck School of Medicine, University of Southern California.