『Abstract
The origin and expansion of biomineralization in eukaryotes played
a critical role in Earth history, linking biological and geochemical
processes. However, the onset of this phenomenon is poorly constrained
due to a limited early fossil record of biomineralization. although
macroscopic evidence for biomineralization is not known until
the late Ediacaran, we here report biologically controlled phosphatic
biomineralization of scale microfossils from mid-Neoproterozoic
(pre-Sturtian) strata of northwest Canada. Primary biological
control on mineralization is supported by the identification of
apatite in both chert-hosted and limestone-hosted specimens, the
conspicuously rigid original morphology of the scale microfossils
relative to co-occurring organic-walled cyanobacteria and acritarchs,
and the microstructure of the constituent phosphate. Cell-enveloping
mineralized scales occur in a wide range of extant protists, but
the apparent restriction of phosphate scales to one modern taxon
of green algae suggests a possible affiliation for these fossils.
Documentation of primary phosphate biomineralization in Fifteenmile
Group (Yukon Territory, Canada) microfossils greatly extends the
known record of biologically controlled mineralization and provides
a unique window into the diversity of early eukaryotes.』
Introduction
Geologic setting
Material and methods
Morphology and composition
Original composition
Taxonomic affinity
Discussion
Conclusion
Acknowledgments
References cited