Response to Comment on “Fossilized Nuclei and Germination Structures Identify Ediacaran ‘Animal Embryos’ as Encysting Protists”
نویسندگان
چکیده
The objections of Xiao et al. to our reinterpretation are based on incorrect assumptions. The lack of nanocrystals lining the nuclear membrane is consistent with membrane fossilization, and nucleus volume through development is correlated to cytoplasm volume and fully consistent with sizes of eukaryote nuclei. Identical envelope structure unites the developmental stages of the fossils, and 2 cleavage and Y-shaped junctions are holozoan symplesiomorphies.
منابع مشابه
Comment on "Fossilized nuclei and germination structures identify Ediacaran 'animal embryos' as encysting protists".
On the basis of putative nuclei and endospores, Huldtgren et al. (Reports, 23 December 2011, p. 1696) propose that embryo-like Doushantuo microfossils are nonmetazoan holozoans akin to mesomycetozoeans. However, both size and preservation preclude interpretation of internal structures as nuclei. Moreover, the authors may have conflated two different populations; some specimens display a pseudop...
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Globular fossils showing palintomic cell cleavage in the Ediacaran Doushantuo Formation, China, are widely regarded as embryos of early metazoans, although metazoan synapomorphies, tissue differentiation, and associated juveniles or adults are lacking. We demonstrate using synchrotron-based x-ray tomographic microscopy that the fossils have features incompatible with multicellular metazoan embr...
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