Agencies that cause disarticulation:

Another style of disarticulation is disintegration during floating. As a carcass floats, it rots and drops body parts in a well defined sequence. For example, in fish, the lower jaw would be the first to drop and then continuing through fin bones, skull bones and scales, until the final mid-body segment at last sinks to the bottom. Carcasses in water disarticulate within weeks to months.

Burial effectively removes carcasses from many large scavengers and retards the rate of soft tissue decomposition and disarticulation. Skeletal disarticulation can continue after burial, by burrowing, which is readily recognizable because it leaves bones oriented obliquely to the bedding.

Just like the fish, these wildebeasts have drifted
down a river. As they would begin to decay they
would lose certain bones and parts before
others, leaving a trail of scattered and disarticulated