title: Demecology in the Cambrian: synchronized molting in arthropods from the Burgess Shale.
abstract: BACKGROUND
  The Burgess Shale is well known for its preservation of a diverse soft-bodied biota dating from the Cambrian period (Series 3, Stage 5). While previous paleoecological studies have focused on particular species (autecology) or entire paleocommunities (synecology), studies on the ecology of populations (demecology) of Burgess Shale organisms have remained mainly anecdotal.
  
  
  RESULTS
  Here, we present evidence for mass molting events in two unrelated arthropods from the Burgess Shale Walcott Quarry, Canadaspis perfecta and a megacheiran referred to as Alalcomenaeus sp.
  
  
  CONCLUSIONS
  These findings suggest that the triggers for such supposed synchronized molting appeared early on during the Cambrian radiation, and synchronized molting in the Cambrian may have had similar functions in the past as it does today. In addition, the finding of numerous juvenile Alalcomenaeus sp. molts associated with the putative alga Dictyophycus suggests a possible nursery habitat. In this nursery habitat a population of this animal might have found a more protected environment in which to spend critical developmental phases, as do many modern species today.
authors.affiliation: Zoological Institute and Museum, Department of Cytology and Evolutionary Biology, Soldmannstrasse 23, 17487 Greifswald, Germany. joachim.haug@palaeo-evo-devo.info
authors.forename: Joachim T
authors.initials: JT
authors.lastname: Haug
authors.forename: Jean-Bernard
authors.initials: JB
authors.lastname: Caron
authors.forename: Carolin
authors.initials: C
authors.lastname: Haug
mesh_terms: D000818:Animals; D001181:Arthropods / Q000502:physiology*; D001955:British Columbia; D055669:Ecological and Environmental Phenomena; D005580:Fossils; D005858:Germany; D018978:Molting; D013997:Time Factors