Devonian period

(redirected from Devonian)
Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.

Devonian period

a geological period lasting from about 415 to 370 million years ago. Many freshwater fish existed during this period and plants became established on land. True seed plants evolved and lycopods reached the size of trees. Amphibians evolved, the first known insects, spiders and mites occurred and most graptolites became extinct. Britain still lay south of the equator with the Thames at 10 °S. See GEOLOGICAL TIME.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
This press release contains forward-looking statements about Devonian's objectives, strategies and businesses that involve risks and uncertainties.
The phacopide trilobites are relatively common in the Sarcheshmeh Member (the uppermost Devonian unit of the Khoshyeilaq Formation) exposed in the eastern Alborz Mountains along the road connecting Shahrud and Azadshahr.
"We now have strong patent protection in North America, strengthening our company's commercial potential," said Devonian's president and CEO, Dr Andre P.
Twelve Devonian tetrapods have previously been described, all of which came from the Devonian tropics, between 30 degrees north and south of the equator.
Previously the age of this succession had been regarded as wholly Early Devonian (Lochkovian or Pragian), based principally on an undescribed ostracod, which Berdan (1990) considered to belong to a quadrilobate beyrichiacean form allied to Cornikloedenina; but it is more like Carinokloedenia from the Pragian of Podolia and the Lochkovian of northern France.
The sedimentary thickness from Devonian to Early Permian is more than 14, 000 m [23, 31].
But all the Silurian, most of the Devonian and a major part of the Carboniferous and Lower Permian sequences are missing.
The research team, which includes Assistant Professor Sarah Carmichael, is examining the relationship between climate change and changes in the ecosystems in the Devonian period, from 419 to 359 million years ago.
Terrestrialisation was believed to have occurred early in their history, probably during the Devonian period, with allegedly aquatic Proscorpiidae coexisting with terrestrial Mesoscorpionina and 'palaeosterns' until the early Carboniferous (Jeram 1998).
If the Jurassic age was 145 million years ago and the Devonian was 359 million years ago, what is the present day epoch called?
King Leopold Ranges; Gogo Fish fossil sites; Kimberley Plateau and Lennard Shelf Devonian reef outcrops; the vine thicket of northern Kimberley coast and islands; Broome sandstone dinosaur trackways; Roebuck Bay; the Kimberley Coast from Buccaneer Archipelago to King George River including offshore islands; Mitchell River National Park; King George Falls; King George River; Geikie Gorge Conservation Park; Windjana Gorge National Park; and King Leopold Range Conservation Park.