Unlocking the early fossil record of the arthropod central nervous system

Gregory D. Edgecombe, Xiaoya Ma, Nicholas J Strausfeld

Research output: Contribution to journalArticle

19 Scopus citations

Abstract

Extant panarthropods (euarthropods, onychophorans and tardigrades) are hallmarked by stunning morphological and taxonomic diversity, but their central nervous systems (CNS) are relatively conserved. The timing of divergences of the ground pattern CNS organization of the major panarthropod clades has been poorly constrained because of a scarcity of data from their early fossil record. Although the CNS has been documented in three-dimensional detail in insects from Cenozoic ambers, it is widely assumed that these tissues are too prone to decay to withstand other styles of fossilization or geologically older preservation. However,CambrianBurgess Shale-type compressions have emergedas sources of fossilized brains and nerve cords. CNS in these Cambrian fossils are preserved as carbon films or as iron oxides/hydroxides after pyrite in association with carbon. Experiments with carcasses compacted in fine-grained sediment depict preservation of neural tissue for a more prolonged temporal window than anticipated by decay experiments in other media. CNS and compound eye characters in exceptionally preserved Cambrian fossils predict divergences of the mandibulate and chelicerate ground patterns by Cambrian Stage 3 (ca 518 Ma), a dating that is compatible with molecular estimates for these splits.

Original languageEnglish (US)
Article number20150038
JournalPhilosophical transactions of the Royal Society of London. Series B: Biological sciences
Volume370
Issue number1684
DOIs
StatePublished - Dec 19 2015

Keywords

  • Arthropoda
  • Brains
  • Burgess shale
  • Cambrian
  • Chengjiang

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'Unlocking the early fossil record of the arthropod central nervous system'. Together they form a unique fingerprint.

Cite this