Whale falls are distributed heterogeneously throughout space and time, with a concentration along migration routes. There is much faunal overlap in these whale falls across oceans. Mussels and vesicomyid clams belong to groups that harbor chemosynthetic bacteria, which can draw energy from inorganic chemicals, such as sulfur. Before their presence was discovered at whale falls, the only known habitats of these groups were sunken wood and hydrothermal vents. Similarly, lucinid clams were previously only known to inhabit carbon seeps and anoxic seafloor sediments. Osedax, a genus of deep-sea polychaete worms, act as ecosystem engineers by excreting acid to erode whale bones and absorbing the nutrients trapped within. This enhances biodiversity in the deep sea by increasing the water diffusion into the matrix of bones and facilitating colonization of the bone matrix by rarer species. Osedax have more dramatic effects in juvenile skeletons, which are not as well-calcified as adult skeletons.