They now know that a whale fall may host even more species than a hydrothermal vent—many unique to whale falls. Recently discovered “blind zombie worms?use an internal “bacterial garden?to break down the whale bone and feed on the fats and proteins inside. “They are an example of extreme evolutionary novelty,?says Smith, “a new feeding strategy that scientists never dreamed of …?Sometimes the worms are so abundant on the whale bones, it looks like a waving lawn of grass. While the first zombie worms were described only a few months ago from one whale skeleton off California, Craig and co-workers have just found another species off Sweden and now think these zombie worms may occur worldwide.
Because of their ability to break down lipids in cold water, these animals and their bacterial garden may hold a key to better cold water washing detergents. But more importantly, study of whale worms and other whale-fall species help scientists understand how life has diversified in specialized habitats in the deep-sea. Deep-sea vent tube worms may have originated from shallow-water species, using whale falls as a food source along the way. “Whale bone worms have been around for 30 to 40 million years. It’s conceivable that whale worms first appeared on whales and later adapted to deep-sea hydrothermal vents,?Smith explains. Whale fall habitats can form underwater stepping-stones—food archipelagos?for the dispersal of deep-sea species. “If you calculate the abundance of whale falls on the sea floor ?say for grey whales in the northeast Pacific, the neighboring whale falls are about 5-10 kilometers away, which is a very reasonable dispersal distance for the animals that live on them,?says Smith.
In the North Atlantic, where only 10% of historic populations of the great whales are estimated to still survive, Smith speculates that substantial species extinction may have occurred in the whal