taphonomy

Taphonomy is the study of the processes that affect an organism from the moment of death to its discovery as a fossil or its inclusion in the fossil record. It encompasses decay, disarticulation, transport before burial, burial, and subsequent diagenetic or lithification changes. Taphonomy also examines biases introduced by differential preservation that influence which organisms and tissues are preserved and in what form.

The field distinguishes biostratinomy, the pre-burial phase including decay, scavenging, sediment entrainment, and transport, from diagenesis, the chemical, physical, and structural modifications that occur after burial. Preservation modes include permineralization, replacement, carbonization, molds and casts, and, when organisms are trapped in amber or preserved in other matrices, exceptional preservation.

Taphonomic analysis informs interpretations of depositional environments, paleocommunities, and the completeness of fossil assemblages, and it helps identify postmortem disturbances such as scavenging or transport that may confound ecological reconstructions. In forensic science, forensic taphonomy applies similar principles to estimate time since death, postmortem interval, and postmortem movement.

A variety of factors influence taphonomic outcomes: the biology and anatomy of the organism, environmental conditions at death (oxygen levels, temperature, moisture), sedimentology and burial rate, chemical composition of surrounding waters, and time. Lagerstätten illustrate how particular conditions can yield extraordinary preservation, whereas other settings produce only sparse or fragmented remains.

Overall, taphonomy connects death, decay, and burial with the fossil record, providing a framework to interpret preservation and bias across geological time.