A controversial claim has been put forth by a researcher at the
University of Oregon that could shake some limbs on the tree of
life. Researcher Gregory Retallack argues that ancient
multicellular fossils previously thought to be ancestors of
early marine life are vestiges of land-dwelling lichen or other
microbial colonies. Mr. Retallack points to Ediacaran fossils as
evidence that land creatures may not have come from the sea.
Ediacaran fossils date to 542-635 million years ago. They have
been thought of as fossil jellyfish, worms and sea pens, but
this researcher says that Ediacaran fossils are preserved in
ways that are completely different from marine invertebrate
fossils. Ediacaran fossils are located in iron-colored
impressions like planet fossils and microbes in fossil soils.