Archaean

¹ British  

/ ɑːˈkiːən /

adjective

1. of or relating to the highly metamorphosed rocks formed in the early Precambrian era

2. the earlier of two divisions of the Precambrian era, during which the earliest forms of life are assumed to have appeared

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archaean ² British  

/ ɑːˈkɪən /

noun

1. any member of the Archaea , a domain of prokaryotic microorganisms, distinguished from bacteria on molecular phylogenetic grounds and often found in hostile environments, such as volcanic vents and hot springs

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Example Sentences

Now, the team hopes to analyze samples from the structures, which it calls “archaean domes,” in search of the elusive Asgard archaea, organisms previously found only in the deep ocean and thought to hold clues to the evolution of simple microbes into complex eukaryotes.

From Science Magazine

These microbes represent many limbs of the archaean evolutionary tree, indicating that salt-loving adaptations emerged many times.

From New York Times

Our measurements show a stepwise total decrease of 0.08 per mille in the average triple-oxygen-isotope value of shales across the Archaean–Proterozoic boundary.

From Nature

We suggest that our data are best explained by a shift in the nature of water–rock interactions, from near-coastal in the Archaean era to predominantly continental in the Proterozoic, accompanied by a decrease in average surface temperatures.

From Nature

Kositcin, N. & Krapež, B. Relationship between detrital zircon age-spectra and the tectonic evolution of the Late Archaean Witwatersrand Basin, South Africa.

From Nature