Darwin's dilemma: the realities of the Cambrian ‘explosion’

2006/05/03 by Simon Conway Morris · 3 citations
Earth and Planetary Sciences · #Paleontology and Stratigraphy of Fossils #Marine Biology and Ecology Research #Geology and Paleoclimatology Research

paper · doi:10.1098/rstb.2006.1846

openalex publication_date 2006/05/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/15

Abstract

The Cambrian 'explosion' is widely regarded as one of the fulcrum points in the history of life, yet its origins and causes remain deeply controversial. New data from the fossil record, especially of Burgess Shale-type Lagerstätten, indicate, however, that the assembly of bodyplans is not only largely a Cambrian phenomenon, but can already be documented in fair detail. This speaks against a much more ancient origin of the metazoans, and current work is doing much to reconcile the apparent discrepancies between the fossil record, including the Ediacaran assemblages of latest Neoproterozoic age and molecular 'clocks'. Hypotheses to explain the Cambrian 'explosion' continue to be generated, but the recurrent confusion of cause and effect suggests that the wrong sort of question is being asked. Here I propose that despite its step-like function this evolutionary event is the inevitable consequence of Earth and biospheric change.

Citations

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