The subduction of the Iapetus Ocean resulted in the first contact between Laurussia and Gondwana in the Late Devonian and terminated in full collision or the Hercynian/Variscan orogeny in the early Carboniferous (340 Mya).
 The Variscan orogeny closed the Rheic Ocean (between Avalonia and Armorica) and the Proto-Tethys Ocean (between Armorica and Gondwana) to form the supercontinent Pangaea.
 The Variscan orogeny is complex and the exact timing and the order of the collisions between involved microcontinent has been debated for decades.

Pangaea was completely assembled by the Permian except for the Asian blocks.
 The supercontinent was centred on the Equator during the Triassic and Jurassic, a period that saw the emergence of the Pangaean megamonsoon.
 Heavy rainfall resulted in high groundwater tables, in turn resulting in peat formation and extensive coal deposits.

During the Cambrian and Early Ordovician, when wide oceans separated all major continents, only pelagic marine organisms, such as plankton, could move freely across the open ocean and therefore the oceanic gaps between continents are easily detected in the fossil records of marine bottom dwellers and non-marine species.
 By the Late Ordovician, when continents were pushed closer together closing the oceanic gaps, benthos (brachiopods and trilobites) could spread between continents while ostracods and fishes remained isolated.
 As Laurussia formed during the Devonian and Pangaea formed, fish species in both Laurussia and Gondwana began to migrate between continents and before the end of the Devonian similar species were found on both side of what remained of the Variscan barrier.

The oldest tree fossils are from the Middle Devonian pteridophyte Gilboa forest in central Laurussia (today New York, United States).

In the late Carboniferous, Laurussia was centred on the Equator and covered by tropical rainforests, commonly referred to as the coal forest.
 By the Permian, the climate had become arid and these rainforests collapsed, lycopsids (giant mosses) were replaced by treeferns.
 In the dry climate a detritivorous fauna – including ringed worms, molluscs, and arthropods – elvolved and diversified, alongside vertebrates – insectivores and piscivores such as amphibians and early amniotes (land-living reptiles).
The subduction of the Iapetus Ocean resulted in the first contact between Laurussia and Gondwana in the Late Devonian and terminated in full collision or the Hercynian/Variscan orogeny in the early Carboniferous (340 Mya).  The Variscan orogeny closed the Rheic Ocean (between Avalonia and Armorica) and the Proto-Tethys Ocean (between Armorica and Gondwana) to form the supercontinent Pangaea.  The Variscan orogeny is complex and the exact timing and the order of the collisions between involved microcontinent has been debated for decades.
Pangaea was completely assembled by the Permian except for the Asian blocks.  The supercontinent was centred on the Equator during the Triassic and Jurassic, a period that saw the emergence of the Pangaean megamonsoon.  Heavy rainfall resulted in high groundwater tables, in turn resulting in peat formation and extensive coal deposits.
During the Cambrian and Early Ordovician, when wide oceans separated all major continents, only pelagic marine organisms, such as plankton, could move freely across the open ocean and therefore the oceanic gaps between continents are easily detected in the fossil records of marine bottom dwellers and non-marine species.  By the Late Ordovician, when continents were pushed closer together closing the oceanic gaps, benthos (brachiopods and trilobites) could spread between continents while ostracods and fishes remained isolated.  As Laurussia formed during the Devonian and Pangaea formed, fish species in both Laurussia and Gondwana began to migrate between continents and before the end of the Devonian similar species were found on both side of what remained of the Variscan barrier.
The oldest tree fossils are from the Middle Devonian pteridophyte Gilboa forest in central Laurussia (today New York, United States).
In the late Carboniferous, Laurussia was centred on the Equator and covered by tropical rainforests, commonly referred to as the coal forest.  By the Permian, the climate had become arid and these rainforests collapsed, lycopsids (giant mosses) were replaced by treeferns.  In the dry climate a detritivorous fauna – including ringed worms, molluscs, and arthropods – elvolved and diversified, alongside vertebrates – insectivores and piscivores such as amphibians and early amniotes (land-living reptiles).
Laurasia