Examples of using Devonian in English and their translations into Serbian
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Cyrillic
Middle Devonian.
It is assumed the proto-caribbean basin existed in the Devonian period.
The first specimens appear during the Devonian period(about 415 million years ago).
Four Devonian taxa tentatively included in the tree presented above are known from fragmentary remains.
Lycophytes first appeared early in the Devonian Period.(about 400 million years ago).
However, the land fauna did not have a major impact on the Earth until it diversified in the Devonian.
The earliest acanthodians were marine, but during the Devonian, freshwater species became predominant.
The Devonian also saw the rise of the first labyrinthodonts, which was a transitional between fishes and amphibians.
This animation presents some animals and plants that lived between the Devonian and Permian periods(358-299 million years ago).
Stegocephalians(see section on classification below for a definition of this group)originated no later than the Upper Devonian.
Only Ichthyostega and other Devonian taxa(Acanthostega, Tulerpeton) were not believed to be on one of these two main evolutionary lineages.
The first jawed vertebrates appeared in the latest Ordovician andbecame common in the Devonian, often known as the"Age of Fishes".
Over four hundred million years ago, in the Devonian period, the genus Eryops was the last common ancestor of both warm-blooded and cold-blooded lifeforms.
The earliest fossils are known from the Cambrian'Orsten' of Sweden,the Silurian Wenlock Series of England and the Devonian Hunsrück Slate of Germany.
Spider-like arachnids with silk-producing spigots appear in the Devonian period about 386 million years ago, but these animals apparently lacked spinnerets.
It has been suggested that global cooling caused or contributed to the End-Ordovician, Permian-Triassic,Late Devonian extinctions, and possibly others.
Discovery of fairly complete specimens of the Devonian choanate Acanthostega(Coates and Clack, 1990) confirms that its limbs were poorly suited to walk on dry land(Zimmer, 1995).
The internal gills may have disappeared fairly early in the Carboniferous, andthere is no trace of lepidotrichia in stegocephalians after the Devonian, and this may indicate a slightly less aquatic lifestyle.
Fossils of aquatic scorpions with gills appear in the Silurian and Devonian periods, and the earliest fossil of an air-breathing scorpion with book lungs dates from the Early Carboniferous period.
It could conceivably represent a more basal form, excluded from the smallest clade that includes Elginerpeton, Ventastega and more crownward forms, andthis would imply a single stegocephalian ghost lineage extending from the Middle through the Late Devonian, in addition to a few ghost lineages in finned tetrapodomorphs(Laurin, 2010; figure, part B).
However, the recent discovery of a Middle Devonian(Eifelian) trackway(Niedzwiedzki et al., 2010) in the abandoned Zachelmie quarry(Poland) makes it more likely that forms such as Elginerpeton possessed digits.
Coates(1991, 1996) suggested that the pentadactyl condition arose twice(at least in the fore limb)because in his proposed phylogenies, the Devonian polydactylous stegocephalian Tulerpeton was believed to be more closely related to amniotes than to lissamphibians.
At the end of the Devonian period(360 million years ago), the seas, rivers and lakes were teeming with life while the land was the realm of early plants and devoid of vertebrates, though some, such as Ichthyostega, may have sometimes hauled themselves out of the water.
Therefore, internal gills were probably lost early in the evolution of stegocephalians, in the Devonian or the Mississippian(about 360 million years ago), and no tetrapod ever had internal gills.
The oldest definitive insect fossil is the Devonian Rhyniognatha hirsti, dated at 396 to 407 million years ago, but its mandibles are of a type found only in winged insects, which suggests that the earliest insects appeared in the Silurian period.
A theory found in most popular books is that the arid climate that was once thought to have prevailed in the Devonian had forced our sarcopterygian ancestors to crawl out of seasonally drying ponds to reach larger, deeper bodies of water(Romer, 1933).
However, a problem with this scenario is that the Devonian is no longer viewed as having been seasonally dry, and classical Late Devonian formations, such as the Escuminac in Quebec, Canada, are now thought to have been estuarine(hence, no seasonal drought could possibly occur, as the sea level is largely independent of seasons).
Ferns first appear in the fossil record 360 million years ago in the late Devonian period but many of the current families and species did not appear until roughly 145 million years ago in the early Cretaceous, after flowering plants came to dominate many environments.