Tracking climate-change-induced biological invasions by metabarcoding archived natural eDNA samplers
Junk, Isabelle; Schmitt, Nina; Krehenwinkel, Henrik
Current Biology 33 (2023), 943-944; online: 25 September 2023
Abstract
In a time of unprecedented environmental change, understanding the response of organisms and ecosystems to change is paramount. However, our knowledge of anthropogenic impacts on ecosystems is limited by a lack of standardized retrospective biomonitoring data. Here, we use a four-decade time series of archived blue mussels to trace spatiotemporal biodiversity change in coastal ecosystems.
The filter-feeding mussels, which were initially collected for pollution monitoring, can serve as natural eDNA samplers, carrying an imprint of the surrounding aquatic community at the time of sampling. By sequencing the preserved DNA, we characterize highly diverse mussel-associated communities and reconstruct the invasion trajectory of an invasive species, the barnacle Austrominius modestus. We quantitatively trace population growth of the invader to the detriment of native taxa and uncover repeated population collapses and reinvasions after cold winters. By providing highly resolved temporal data on community assembly and global warming-driven invasion processes, natural eDNA sampler time series overcome a critical shortfall in our understanding of biodiversity change in the Anthropocene.