I am an environmental physiologist who takes a comparative approach to understanding how animals are adapted to survive in harsh environments. My current research program is mainly focused on what limits most fish species to live in either fresh or salt water, while others can tolerate a wide range of environmental salinity. To do so, I study the role and regulation of the sodium pump in osmoregulation and how the expression of different isoforms of this protein may limit the salinity tolerance of fishes. My research focuses on several euryhaline fish groups including the salmonids (salmon, trout and charr), sturgeons, killifish, stickleback and poeciliids (guppies, swords, mollies).