This 22 April 2020 video from the USA says about itself:
How do barnacles survive environmental changes? Long-term work by a Brown University research team, with funding from the National Science Foundation, has confirmed that a central metabolic protein Mpi and the gene encoding the protein is what helps the barnacle survive extreme environmental changes.
Different versions of the Mpi enzyme are present at different levels, depending on where the barnacles have settled in the rocky shoreline. One form performs well under high stress, like on a hot day at low tide; the other form does better under low stress. This allows barnacles to survive and prosper in fluctuating extremes and has prepared them for success in an ever-changing environment.