Adaptive Plasticity · Vertebrate Evolution · Genomics & Transcriptomis
How does plasticity evolve and how is it regulated on a molecular level? That's what we are here to figure out.
Adaptive plasticity has long been known to help populations and species rapidly match their environment. But how does plasticity do this? And what does that mean for evolution? Our lab focuses on shedding light on the genetic basis of phenotypic plasticity and to understand the mechanisms behind it. Whether it means to understand how gene expression is affected, cells change, or developmental trajectories fork under different environmental circumstances
Ultimately, we want to find the answer to some long lasting questions and theories of adaptive plasticity.
Phenotypic plasticity, the ability of an organism to change its characteristics with changes in the environment, is an important mechanism by which populations can survive and flourish. Especially in our time, where human-induced environmental changes occur all around the globe, it is important to understand how populations can produce different characters from the same genetic code to deal with these environmental changes. Additionally, our understanding of how this ability evolved is still limited.
The goal is to clarify:
- What are the mechanisms that allow populations to change (i.e., to show plasticity) and
- How does this ability evolve?
The Trinidadian guppy Poecilia reticulata offers an amazing and well-established system to address these questions. In a long-term selection experiment we will expose guppies to different light environments and track the evolution of color vision on a molecular and behavioral level. Cutting-edge methods will be used to understand the genomic, transcriptomic and mechanistic basis of color vision and color vision plasticity.
Past Work
Heterochronic opsin expression due to early light deprivation results in drastically shifted visual sensitivity in a cichlid fish: Possible role of thyroid hormone signaling
Color vision under water can be challenging, because the light under water changes drastically with depth and turbidity. These factors can change throughout the life-time of a fish. To be best suited for under-water vision, cichlid fishes adapt to match their needs at different stages during development. The different stages can be affected strongly by different light environments, but the strongest effect can be observed when fish are reared in complete darkness: color vision progresses through all the developmental stages within only few days and reaches an almost adult phenotype in very young embryos. The explanation for this is … Read more
Reverting ontogeny: rapid phenotypic plasticity of colour vision in cichlid fish
The light environment of fishes can change rapidly, for example, due to algal blooms or pollution. Such events can drastically shift the light from blue light in clear waters to more green or red light. Can fish adapt to such rapid changes to maintain visual functions? For cichlid fishes, this is true. Within few days Nicaraguan cichlids can match their color vision to their environment. This process is not only a one-way road where fish rapidly adapt to different wavelengths of light, they can reverse changes when their light environment changes a second time. At least as juveniles… Read more
A Genomic Cluster Containing Novel and Conserved Genes is Associated with Cichlid Fish Dental Developmental Convergence
One of the hypothesized reasons why cichlid fishes are among the most species rich vertebrate groups are their incredibly diverse and well adapted pharyngeal jaws. Depending on the food items different species feed on, they develop different phenotypes. For example, species feeding on soft items like algae develop countless small and pointed teeth to shred their food. Other species that feed on hard items like snails develop few large and massive teeth. These two extreme phenotypes evolved numerous times independently in different cichlid species. We have shown that gene birth gave rise to … Read more
Differential Regulation of Opsin Gene Expression in Response to Internal and External Stimuli
The Nicaraguan Midas cichlids rapidly adapted to new light environment. One hypothesis is that developmental mechanisms were co-opted during adaptation. Since plasticity evolved in rapidly as well, we assumed that even here developmental mechanisms could have been co-opted to allow for plasticity to rapidly evolve. We tested this hypothesis with a combination of light environment and thyroid hormone treatments. We found that plasticity and development (mimicked by changes in thyroid hormone levels) were independent mechanisms and little overlap can be observed in the…Read more
Supported By
