The strange life form 500 million years ago wasn’t an animal at all: ScienceAlert

We have a strange case of mistaken identity that needs to be reported. The fossils were previously thought to have been left by prehistoric tentacle-bearing aquatic invertebrates freezes It may actually have been created by a different source: seaweed.

That’s the conclusion of a new study of the 500-million-year-old remains, which has taken a fresh look at them Primary fission gates excavations it He thought to represent the oldest recorded Bryozoans remains.

In addition to seemingly setting the record straight, the findings again change what we know about the evolution of Bryozoans. To date, they are the only fossilized animals that have not been around Cambrian explosionwhen life on Earth really began to accelerate.

“We tend to think of the Cambrian Explosion as a unique period in evolutionary history in which all the blueprints for animal life were drawn,” He says Paleontologist Martin Smith, of Durham University in the UK. “Most of the later development boiled down to smaller-scale tinkering with these original body plans.”

“But if Bryozoans really did evolve after the Cambrian period, it shows that evolution preserved its creative touch after this crucial period of innovation—the course of life might not have been well defined half a billion years ago.”

The study authors examined a small P.gateshousei Fossils found in the hills of southern China, separate from the group identified as bryozoans, have discovered previously unseen evidence of soft parts in their specimens.

These new discoveries make these fossils more suitable for green algae, in a group known as dacicladalisparticularly in signs of an outer membrane that was not present in other fossil specimens, the new study suggests.

This, in turn, could teach us more about the Cambrian Explosion: it is very likely that these algae played a more important role than previously thought in the rapidly increasing biodiversity that occurred at the time.

“Where previous fossils had only preserved the skeleton of these early organisms, our new material has revealed what used to live inside these chambers.” He says Paleontologist Zhang Xiguang, of Yunnan University in China.

“Instead of the tentacles we’d expect to see in Bryozoans, we detected simple leaf-like edges — and realized we weren’t looking at fossil animals, but rather at seaweed.”

This means that the oldest Briozoan fossils that experts are most certain of will not appear until the geological period after the Cambrian, Ordovician period – roughly 40 million years after the date of these fossils.

The mysterious case of lost bryozoan fossils has apparently been opened again. Why is this class of creatures the only ones that did not appear in one of the most sudden explosions of life in the history of living things?

One answer may be that we haven’t found the right clues yet. It’s possible that the first forms of Bryozoans had softer parts, which means they didn’t leave behind fossils in the early stages of their evolution.

“An increasing number of Cambrian fossils…display characteristics reconcilable with a bryozoic affinity—but on the basis of currently available material, no taxonomy can be interpreted with a sufficient degree of certainty to document a pre-Ordovician origin of the bryozoa,” He writes The researchers in their published paper.

Research published in nature.