Until now, the oldest traces of motility (an organism is able to move independently with the help of metabolic energy) of about 600 million years ago. But now, newly analyzed fossils suggest that the mobility of the data back to 2.1 billion years ago. (Scale: 1 cm, or 0.4 inch.)
(A. El Albani/IC2MP/CNRS – Université de Poitiers)
About 2.1 billion years ago, a blob-like creature inched along on a young Earth. If the organism moved, carved tunnels, which may be the earliest evidence of a moving creature on this planet.
Until this discovery, the earliest evidence of motility, that is, an organism is able to move independently using its own metabolic energy, dated at about 570 million years ago, according to the fossils of the different locations. That is a good 1.5 billion years younger than the new.
What links the teeny, tiny tunnels was probably a cluster of cells that are in the grades form of a slug-like multicellular organism, the researchers said. And maybe, this sluggy conglomerate a tunnel through the mud in search of greener pastures or food to eat, the international team of scientists said. [In Images: The Oldest Fossils on Earth]
However, not everyone agrees that these tunnels were created by complex life, and a researcher, not affiliated with the study, called the claims “inaccurate.”
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The researchers found the traces of the fossils in the tour of Gabon, along Africa’s west coast. A trace fossil is a fossil that is not part of an organism in the body that it leaves behind, like a footprint, a burrow or even poop. In this case, the trace fossils are a series of narrow tunnels which were created in what was once called Francevillian inland sea, an oxygenated shallow marine environment that existed during the Paleoproterozoic, an era with a duration of approximately 2.5 billion euros to 1.6 billion years ago.
After collecting hundreds of copies of the old inland sea, the scientists in the recent study found fossilized tunnels. These structures indicate that some ancient multicellular organisms were complex enough to scoot through the mud, says first author, Abderrazak El Albani, a professor of environment and geochemistry at the IC2MP, an institute of the University of Poitiers and the National Centre for Scientific Research (CNRS) in France.
There is a modern analogue to these strange slug-like creature. In times of hunger, and some cellular slime molds together in what is called a “migrating slug stage,” so they can look for food together, El Albani said.
The tunnels of these ancient creatures left behind are small, with a maximum diameter of 2.3 inches (6 cm) and a length of 6.7 inch (17 cm). What’s more, the tunnels seem to be something that is laterally and vertically through the slush, El Albani said Live Science. To determine for sure that these tunnels were left by living creatures, the researchers analysed the structures in different ways. For starters, the scientists used an X-ray computed microtomography (micro-CT) scan to analyze the model in 3D (see above video).
The team analyzed the chemical components in the trail of the fossils, find that these traces were of biological origin and are also tailored to the age of 2.1 billion year old sediment around them. In addition, the tunnels were next petrified microbial mats, known as biofilms. Perhaps it is strange, slug-like beast to graze on these microbial “carpets” the researchers said.
While much about this critter remains a mystery, its existence raises new questions about the history of life, El Abani said. This Was the first time that a complex organism moved, and traffic was perfected later? Or was this the creature experiment short when oxygen levels dropped drastically to about 2 billion years ago, just for this kind of movement to resurface much later? [7 Theories on the Origin of Life]
But not everyone thinks that these tunnels represent the oldest evidence of motility.
“The claim sounds really inaccurate,” Tanja Bosak, a professor of geobiology in the Department of Earth, atmospheric and Planetary Sciences at the Massachusetts Institute of Technology, told Science in an e-mail. “Maybe they are referring to something macroscopic to move — there are much older rocks (stromatolites) with shapes and textures that require the former presence of motile bacteria.”
She stresses that she had no time for a thorough reading of the study, Bosak told Live Science, “I hope that they discuss this somewhere, and the tone of the optimistic claims at least a little bit.”
The study was published online yesterday (Feb. 11) in the journal Proceedings of the National Academy of Sciences.
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Originally published on Live Science.