Molecular clocks and the early evolution of metazoan nervous systems.

Journal Article (Review;Journal Article)

The timing of early animal evolution remains poorly resolved, yet remains critical for understanding nervous system evolution. Methods for estimating divergence times from sequence data have improved considerably, providing a more refined understanding of key divergences. The best molecular estimates point to the origin of metazoans and bilaterians tens to hundreds of millions of years earlier than their first appearances in the fossil record. Both the molecular and fossil records are compatible, however, with the possibility of tiny, unskeletonized, low energy budget animals during the Proterozoic that had planktonic, benthic, or meiofaunal lifestyles. Such animals would likely have had relatively simple nervous systems equipped primarily to detect food, avoid inhospitable environments and locate mates. The appearance of the first macropredators during the Cambrian would have changed the selective landscape dramatically, likely driving the evolution of complex sense organs, sophisticated sensory processing systems, and diverse effector systems involved in capturing prey and avoiding predation.

Full Text

Duke Authors

Cited Authors

  • Wray, GA

Published Date

  • December 2015

Published In

Volume / Issue

  • 370 / 1684

Start / End Page

  • 20150046 -

PubMed ID

  • 26554040

Pubmed Central ID

  • PMC4650124

Electronic International Standard Serial Number (EISSN)

  • 1471-2970

International Standard Serial Number (ISSN)

  • 0962-8436

Digital Object Identifier (DOI)

  • 10.1098/rstb.2015.0046


  • eng