Research sheds new light on 'world's oldest animal fossils'
A team of researchers, led by the University of Bristol, has uncovered that ancient fossils, thought to be some of the world's earliest examples of animal remains, could in fact belong to other groups such as algae.
|A spiny acritarch from the Doushantuo biota imaged using synchrotron tomography. The affinities |
of these fossils are unknown [Credit: John Cunningham, University of Bristol]
Dr John Cunningham from the University of Bristol's School of Earth Sciences, said: "Dated at around 600 million years old, these rocks preserve an assemblage of microscopic fossils, perfectly-aged to be candidates for the oldest evidence of animal life. These fossils aren't recognisable as remains of fully grown animals, but some resemble embryos, ranging from single cells to clusters of thousands. The preservation is so exquisite, that even sub-cellular structures can be identified, including possible nuclei."
|A fossil alga from the Doushantuo biota imaged using synchrotron tomography. The specimen has been |
virtually cut to reveal the internal anatomy. These fossils are thought to be red algae
[Credit: John Cunningham, University of Bristol]
Now scientists have reviewed all the evidence pointing towards an animal identity of the Weng'an fossils. Their findings have revealed that none of the characteristics previously used to define the fossils as animals are actually unique to animals alone, opening up the possibility for alternative identifications.
Dr Cunningham added: "It could be that the fossils belong to other groups, such as algae, and these possibilities need to be investigated carefully."
Despite these results, paleontologists are continuing to make new discoveries from the Weng'an Biota, and these are helping to refine our knowledge of evolution during the Ediacaran.
Dr Cunningham concluded: "It might be possible that we'll find definite animals in the Doushantuo Formation, but it'll be like finding a needle in a haystack, or should we say an embryo in a really, really big quarry."
The findings are published in Journal of the Geological Society.
Source: University of Bristol [May 03, 2017]