Death assemblages—the skeletal remains of organisms preserved in modern sediments—provide a unique window into ecological and environmental change across timescales that often exceed direct observation. Long used by paleontologists to investigate taphonomic processes, these subfossil accumulations are increasingly recognized as ecological archives with applications to contemporary conservation and environmental management. In this seminar, I explore how death assemblages from benthic shellfish can be used to address questions spanning paleoecology, community ecology, and conservation biology. Drawing on collaborations with public biomonitoring programs, I show how the dead record can help evaluate whether skeletal remains faithfully capture community structure, identify responses to biological invasions and other anthropogenic stressors, and reveal how environmental conditions influence patterns of skeletal accumulation and preservation. I also discuss emerging work on feedbacks between shell-rich sediments and living communities, highlighting how taphonomic processes can actively shape ecological habitats rather than merely record them. Together, these examples illustrate how death assemblages serve not only as records of the past, but also as powerful tools for understanding and managing environmental change in the present and future.