Invasive vs. Native Marine Mussels (Mytilus)
Evolution and past environmental history can influence how species interact today. On the West Coast of North America, the Mediterranean mussel, Mytilus galloprovincialis, is an invasive species that has displaced the native, Mytilus trossulus, along the southern edge of its former range. These two species exhibit different physiological tolerances to extreme temperature and salinity; the invasive species has greater heat tolerance, while the native species can tolerate lower salinity. Our research has shown that these physiological differences are underlain by the differential regulation of key genes. Thus, species differences at the molecular level underlie differences in whole-organism physiology.
How does molecular physiology influence invasive vs. native biogeographic patterns? This work suggests that molecular physiology facilitates the success of this invasive mussel species in southern California. Accordingly, we might predict that global warming will lead to a range expansion of invasive M. galloprovincialis. However, climate change will likely lead to changes in both temperature and coastal salinity conditions; therefore the further spread of this invasive species remains uncertain.