Complex sentence: Some supporters of the drift theory state that in Australia, vegetation that is uncommon in swamps, such as pine trees, have been found in some coal seams, and that the rocks found around coal seams are sedimentary in nature.
Split into simpler sentences: Some supporters of the drift theory state that in Australia, vegetation that is uncommon in swamps, such as pine trees, have been found in some coal seams. They also state that the rocks found around coal seams are sedimentary in nature.