Journal
NATURE ECOLOGY & EVOLUTION
Volume 1, Issue 10, Pages 1455-1464Publisher
NATURE PUBLISHING GROUP
DOI: 10.1038/s41559-017-0301-9
Keywords
-
Categories
Funding
- CNPq-Conselho Nacional Desenvolvimento Cientifico e Tecnologico- Brazil [451245/2012-1]
- NERC Isotope Geoscience Facilities Steering Committee grant [IP-1560-0515]
- Natural Environment Research Council [NE/L011409/2, NE/L501554/1]
- Sao Paulo Research Foundation (FAPESP), Brazil [2009/02312-4, 2010/02677-0, 2013/17835-8, 2016-06114-6]
- NSERC discovery grant
- St. Anne's College, University of Oxford
- NERC [nigl010001, NE/P013775/1, NE/L011409/2] Funding Source: UKRI
- Natural Environment Research Council [NE/L011409/2, nigl010001] Funding Source: researchfish
Ask authors/readers for more resources
The evolutionary events during the Ediacaran-Cambrian transition (similar to 541 Myr ago) are unparalleled in Earth history. The fossil record suggests that most extant animal phyla appeared in a geologically brief interval, with the oldest unequivocal bilaterian body fossils found in the Early Cambrian. Molecular clocks and biomarkers provide independent estimates for the timing of animal origins, and both suggest a cryptic Neoproterozoic history for Metazoa that extends considerably beyond the Cambrian fossil record. We report an assemblage of ichnofossils from Ediacaran-Cambrian siltstones in Brazil, alongside U-Pb radioisotopic dates that constrain the age of the oldest specimens to 555-542 Myr. X-ray microtomography reveals three-dimensionally preserved traces ranging from 50 to 600 mu m in diameter, indicative of small-bodied, meiofaunal tracemakers. Burrow morphologies suggest they were created by a nematoid-like organism that used undulating locomotion to move through the sediment. This assemblage demonstrates animal-sediment interactions in the latest Ediacaran period, and provides the oldest known fossil evidence for meiofaunal bilaterians. Our discovery highlights meiofaunal ichnofossils as a hitherto unexplored window for tracking animal evolution in deep time, and reveals that both meiofaunal and macrofaunal bilaterians began to explore infaunal niches during the late Ediacaran.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available