Fossils 555 million years of human ancestors

The researchers found the tiny rice-like worm-like creature, the oldest ancestor on a pedigree tree consisting of humans and most animals.

The worm-like creature called Ikaria wariootia lived 555 million years ago. It is considered the earliest symmetric species to appear. Symmetrical animals on both sides have front and back, left and right.

The restored figure of Ikaria wariootia.(Photo: CNN).

Geology professor Mary Droser and PhD student Scott Evans at the University of California, Riverside, USA, examine fossil caves dating back to the end of the Ediacara period 555 million years ago in Nilpena, South Australia, by dynamite symmetrical objects created by the two sides . But the researchers found no evidence that any species lived in caves. Upon closer inspection, they saw an oval trace near the cave.

The results of the 3D laser scan reveal that the remains of the creature with a body shape and the size of a rice grain have a recognizable head and tail and V-shaped grooves like muscle fibers. Muscle contraction helps it move and burrow. The team also identified it as having a mouth, intestines and anus. The size of the creature also matches the caves the researchers found. They published their findings in the journal Proceedings of the National Academy of Sciences on March 23.

Professor Droser and colleagues named the creature Ikaria wariootia, which means "meeting place" in the Aboriginal adnyamathanha of the fossil found Australian area. Ikaria finds and eats organic matter by burrowing through the sand at the bottom of the sea. The team speculated it had basic senses based on the groove groove.

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