A breakdown in disparity between Gondwanan and Laurasian marginal marine ecosystems towards the end of the Devonian has previously been noted, possibly caused by increasing proximity of Laurasia
to Gondwana (Young 1987).
The researchers believe a barrier free connection would have allowed the beasts' migration from Laurasia
and Gondwana - the northernmost parts of Pangea - to the southern tip of the continent.
If you look up Gondwana, you will see in the Late Triassic an area between Gondwana (South America, Africa, India, Antarctica and Australia) and Laurasia
(North America, Europe and Asia) called the Tethys Sea.
At the time of divarication, Laurasia
, still intact, would have facilitated movement between regions.
During the Triassic, the Earth's continents were united as Pangaea, with one southern landmass known as Gondwana and one northern one known as Laurasia
. Africa was part of Gondwana, which is also where most of the Triassic dinosaur fossils have been found.
About 200 million years ago, Pangaea (super continent) broke into two new continents, Laurasia
existing as a part of the split, in the late Mesozoic era and Gondwanaland.
Presumably the early angiosperms radiated into Laurasia
in the region of what is now North Africa, the Iberian Peninsula, and the Middle East.
As late as 120 million years ago, many of the landmasses that we identify as continents today fit together like two giant puzzle pieces: Gondwana in the southern hemisphere and Laurasia
in the northern hemisphere.
The Kazakhstan and North China plates form a part of eastern Laurasia
which had accreted by late Devonian times; the part of Myanmar which produces Cretaceous amber (Grimaldi et al.