<Ol> <Li> Mobile scavenger stage: Big and mobile deep - sea animals arrive at the site almost immediately after whales fall on the bottom . Amphipods, crabs, sleeper sharks and hagfish are all scavengers . </Li> <Li> Opportunistic stage: Organisms arrive which colonize the bones and surrounding sediments that have been contaminated with organic matter from the carcass and any other tissue left by the scavengers . One genus is Osedax., a tube worm . The larva is born without sex . The surrounding environment determines the sex of the larva . When a larva settles on a whale bone, it turns into a female; when a larva settles on or in a female, it turns into a dwarf male . One female Osedax can carry more than 200 of these male individuals in its oviduct . </Li> <Li> Sulfophilic stage: Further decomposition of bones and seawater sulfate reduction happen at this stage . Bacteria create a sulphide - rich environment analogous to hydrothermal vents . Polynoids, bivalves, gastropods and other sulphur - loving creatures move in . </Li> </Ol> <Li> Mobile scavenger stage: Big and mobile deep - sea animals arrive at the site almost immediately after whales fall on the bottom . Amphipods, crabs, sleeper sharks and hagfish are all scavengers . </Li> <Li> Opportunistic stage: Organisms arrive which colonize the bones and surrounding sediments that have been contaminated with organic matter from the carcass and any other tissue left by the scavengers . One genus is Osedax., a tube worm . The larva is born without sex . The surrounding environment determines the sex of the larva . When a larva settles on a whale bone, it turns into a female; when a larva settles on or in a female, it turns into a dwarf male . One female Osedax can carry more than 200 of these male individuals in its oviduct . </Li> <Li> Sulfophilic stage: Further decomposition of bones and seawater sulfate reduction happen at this stage . Bacteria create a sulphide - rich environment analogous to hydrothermal vents . Polynoids, bivalves, gastropods and other sulphur - loving creatures move in . </Li>

The main source of light in the deep sea is