Ediacara biota
Retallack discovered fossil soils at classical South Australian sites for the Ediacara biota and reported it is evidence that these fossils formerly regarded as marine were instead terrestrial organisms such as lichens, slime molds and microbial colonies. Retallack has also reinterpreted volcanic tuffs of Newfoundland as terrestrial lapilli and sanidine tuffs, and so found fossiliferous Ediacaran paleosols there as well