Ultrastructure, morphology, and topology of Cambrian palynomorphs from the Lone Rock Formation, Wisconsin, USA
نویسندگان
چکیده
animal life on land. The current benchmark for evidence of plants on land is about 450,000,000 years ago (Late Ordovician). Tantalizing microscopic fossils of chemically resistant spore walls occur in land-derived rocks around the world, and predate this Late Ordovician age by over 50,000,000 years (Upper Cambrian) and possibly beyond. Figuring out what kinds of organisms (algae, primitive plants, or something in between) produced these spores has proven to be a challenge that we have chosen to address with the use of powerful instruments called electron microscopes. Ultrastructure, Morphology, and Topology of Cambrian Palynomorphs from the Lone Rock Formation, Wisconsin, USA
منابع مشابه
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