PALEOCOMMUNITY RECONSTRUCTION AND ACCUMULATION OF MICROMAMMALIANREMAINS (LATE EOCENE, SOUTHERN ENGLAND)

摘要

A taphonomic study was conducted on disarticulated micromammalianbones and isolated teeth from a late Eocene (Priabonian) assemblage inthe Headon Hill Formation (Solent Group, Hampshire Basin, Isle ofWight, United Kingdom). The aim was to understand accumulatingmechanisms and additional postmortem agents that influenced andpotentially biased the assemblage. Skeletal elements (N = 4296) belongto three marsupials, two glirid and two theridomyid rodents, twochiropterans, three nyctitheres, two omomyid primates, one pantolestid,and one apatothere. Surface modifications (i.e., etching, breakage,splitting, and impact marks) occur on bone, enamel, and dentine.Qualitative and quantitative analyses of surface modifications of eachindividual taxon resulted in recognition of several taphonomic agents.Predation of two theridomyid and at least two marsupial species by themammalian carnivore Cynodictis cf. lacustris (also present in the fauna) isindicated by high proportions of etched remains, broken bones, andpuncture marks. Variations within the assemblage in proportions ofmodified specimens or numbers of individuals are interpreted as reflectingdifferences in cause of death, habits, locomotor adaptations, and predator-prey relationships. The rodents, marsupials, and probably the nyctitheresare judged to have been living close to the site of deposition, justifyingtheir previous use for isotope-based paleoclimate studies and demonstrat-ing their participation in the local paleocommunity.