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The DOI matches its Crossref record; 4 of the 4 references it cites were found in a registry or an index.

Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan

Han, Tsu-Ming, Runnegar, Bruce·1992·Science
DOI 10.1126/science.1631544
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Abstract

Hundreds of specimens of spirally coiled, megascopic, carbonaceous fossils resembling Grypania spiralis (Walcott), have been found in the 2.1-billion-year-old Negaunee Iron-Formation at the Empire Mine, near Marquette, Michigan. This occurrence of Grypania is 700 million to 1000 million years older than fossils from previously known sites in Montana, China, and India. As Grypania appears to have been a photosynthetic alga, this discovery places the origin of organelle-bearing eukaryotic cells prior to 2.1 billion years ago.

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Metadata

Authors
Han, T.-M., & Runnegar, B.
Venue
Science
Publisher
American Association for the Advancement of Science (AAAS)
Published
1992-07-10
Volume
257
Issue
5067
Pages
232-235
ISSN
  • 0036-8075 (ISSN-L)
  • 1095-9203
DOI
10.1126/science.1631544
OpenAlex
W1992853665
Cited by
469
References
4
FWCI
22.67
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan. https://app.cochat.ai/papers/10.1126/science.1631544
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Han, T.-M., & Runnegar, B. (1992). Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan. Science. https://doi.org/10.1126/science.1631544

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