stro·​mat·​o·​lite | \ strō-ˈma-tə-ˌlīt How to pronounce stromatolite (audio) \

Definition of stromatolite

: a laminated usually mounded sedimentary fossil formed from layers of cyanobacteria, calcium carbonate, and trapped sediment

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Other Words from stromatolite

stromatolitic \ strō-​ˌma-​tə-​ˈli-​tik How to pronounce stromatolitic (audio) \ adjective

Examples of stromatolite in a Sentence

Recent Examples on the Web

Their first observation is the simplest—there's a problem with the shape of the purported stromatolites. Scott K. Johnson, Ars Technica, "New study argues against some of the oldest evidence for life," 18 Oct. 2018 Some of Earth's oldest fossils come in the form of stromatolites: layered structures created by aquatic colonies of photosynthetic microbes called cyanobacteria. National Geographic, "6 Amazing Structures Built by Surprising Creatures," 7 May 2018 According to a 2016 study in Scientific Reports, stromatolites dominated Earth's fossil record for four-fifths of our planet's history, with some of the oldest stromatolites yet found ranging from 3.48 to 3.7 billion years old. National Geographic, "6 Amazing Structures Built by Surprising Creatures," 7 May 2018 They are called stromatolites, a microbial mat formed in shallow water by trapping and binding sedimentary grain by biofilms. Brian E. Clark, Milwaukee Journal Sentinel, "A mastodon and a meteor older than Earth are highlights of the UW Geology Museum," 9 Mar. 2018 The region is full of stromatolites, layers of rock that were produced by ancient photosynthesizing bacteria that grew in moist mats and trapped layers of sediments over time. Ben Panko, Smithsonian, "Fossils From Ancient Hot Springs Suggest Life May Have Evolved on Land," 11 May 2017 Stromatolites today are often found in saltwater environments, which is why scientists have for decades assumed that the Dresser Formation was once an ocean shoreline. Ben Panko, Smithsonian, "Fossils from Ancient Hot Springs Suggest Life May Have Evolved on Land," 11 May 2017 But even with samples from our home planet, not all scientists are convinced that these ancient structures are fossils, since stromatolites can form without the assistance of microbial mats. National Geographic, "NASA’s Bold Plan to Hunt for Fossils on Mars," 17 Oct. 2016 Ancient rocks in Greenland that date to 3.7 billion years ago contain hints of microbial mats of cyanobacteria known as stromatolites, while another formation in Quebec may date back 4.28 billion years. Fox News, "Scientists may have discovered the oldest evidence of life on land," 11 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'stromatolite.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of stromatolite

1930, in the meaning defined above

History and Etymology for stromatolite

Latin stromat-, stroma bed covering + English -o- + -lite

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The first known use of stromatolite was in 1930

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to reflect, repel, echo, or resound

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