Preservation of species abundance in marine death assemblages

Fossil assemblages of skeletal material are thought to differ from their so urce live communities, particularly in relative abundance of species, owing to potential bias from postmortem transport and time-averaging of multiple generations. However, statistical meta-analysis of 85 marine molluscan dat a sets indicates that, although sensitive to sieve mesh-size and environmen t, time-averaged death assemblages retain a strong signal of species' origi nal rank orders. Naturally accumulated death assemblages thus provide a rel iable means of acquiring the abundance data that are key to a new generatio n of paleobiologic and macroecologic questions and to extending ecological time-series via sedimentary cores.