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middle devonian
In the geological timescale, the Middle Devonian epoch (from 393.3 ± 1.2 million years ago to 382.7 ± 1.6 million years ago) occurred during the Devonian period, after the end of the Emsian age.
devonian period
Age of fishes, early amphibians.
devonian age
Geological period of fish diversification.
devonian system
Late Devonian extinction
The Late Devonian extinction consisted of several extinction events in the Late Devonian Epoch, which collectively represent one of the five largest mass extinction events in the history of life on Earth.
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