This pandemic year has seen us confined to our homes and restricted from travelling the world. Not so for some microscopic bacteria in the ocean: Throughout the globe, they partner up with clams from the family Lucinidae, which live unseen in the sand beneath the shimmering blue waters of coastal habitats. This partnership is the clams’ passport to their extensive global reach. The bacteria can also travel a long way. According to research by scientists from the Max Planck Institute for Marine Microbiology in Bremen and the University of Vienna now published in PNAS, the bacterial symbionts living in lucinid gills can travel the world without borders.