Publications
Following publications have been announced by our department Biological Carbon Pump. For further information please contact Dr. Jana Hinners, author resp. co-author of the publications:
Hinners J., Argyle, P.A., Walworth, N.G., Doblin, M.A., Levine, N.M., & Collins, S. (2024): Multi-trait diversification in marine diatoms in constant and warmed environments. Proc. R. Soc., B. 291, 20232564, doi:10.1098/rspb.2023.2564
Abstract:
Phytoplankton are photosynthetic marine microbes that affect food webs, nutrient cycles and climate regulation. Their roles are determined by correlated phytoplankton functional traits including cell size, chlorophyll content and cellular composition. Here, we explore patterns of evolution in interrelated trait values and correlations. Because both chance events and natural selection contribute to phytoplankton trait evolution, we used population bottlenecks to diversify six genotypes of Thalassiosirid diatoms. We then evolved them as large populations in two environments. Interspecific variation and within-species evolution were visualized for nine traits and their correlations using reduced axes (a trait-scape). Our main findings are that shifts in trait values resulted in movement of evolving populations within the trait-scape in both environments, but were more frequent when large populations evolved in a novel environment. Which trait relationships evolved was population-specific, but greater departures from ancestral trait correlations were associated with lower population growth rates. There was no single master trait that could be used to understand multi-trait evolution. Instead, repeatable multi-trait evolution occurred along a major axis of variation defined by several diatom traits and trait relationships. Because trait-scapes capture changes in trait relationships and values together, they offer an insightful way to study multi-trait variation.
Hochfeld, I., & Hinners, J. (2024): Evolutionary adaptation to steady or changing environments affects competitive outcomes in marine phytoplankton. Limnol Oceanogr, 69: 1172-1186, doi:10.1002/lno.12559
Abstract:
The interplay of phytoplankton competition and adaptation affects how phytoplankton, and ultimately marine ecosystems, respond to global warming. However, current ecosystem models that are run under global warming scenarios do not include both processes simultaneously. To fill this gap, we developed an innovative ecosystem model for the Baltic Sea that simulates competition between three phytoplankton functional groups and allows for adaptation to changing temperatures. As adaptation can be affected by the resuspension of dormant resting cells from the sediment, we explicitly implemented this mechanism. We found that resuspension tends to slow down adaptation, and that competition and adaptation influence each other. The outcome of the competition-adaptation interplay depends on environmental conditions. In a steady environment, competition drives adaptation to individual temperature niches to reduce competition pressure. In a changing environment, adaptation allows inferior competitors to mitigate the dominance of preadapted superior competitors. Our results demonstrate that by neglecting adaptation, models can systematically overestimate warming-related changes in taxa dominance. Ecosystem models should include both competition and adaptation to accurately simulate phytoplankton responses to global warming. Our model is ideally suited to integrate emerging evolutionary data based on long-term data series (e.g., from sediment archives) to further improve projections of future ecosystem change.
