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Hallucigenia
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Weird fossil worm with legs and spikes finally reveals its head

Hallucigenia was a worm-like marine animal with legs, spikes and a head that is difficult to distinguish from its tail. It is only a few centimetres long, and its body is as thin as a pin.
This enigmatic 508-million-year-old worm-like creature has been tricking scientists since the 1970s. Reconstructions of what it would have looked like had it upside down, on its side and even back to front.
Now Martin Smith of the University of Cambridge and his colleagues think they finally have the correct description of this creature, which lived during the Cambrian explosion when most major animal groups first emerge in the fossil record.

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RE: Ancient life
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Title: Paleoarchean trace fossils in altered volcanic glass
Author: Hubert Staudigel, Harald Furnes, and Maarten DeWit

The dawn of sustainable life on earth is preserved in the form of fossil or chemical evidence in ancient rock sequences, such as the Barberton Greenstone Belt in South Africa. Studies of sedimentary rocks offered a glimpse at life at the earth's surface, and trace fossils in pillow lavas offered evidence for a potential deep biosphere back in time to the Paleoarchean. Recent data cast doubt on the biogenicity of these putative trace fossils, rejecting their potential in exploring a deep biosphere. We discuss biogenicity of Cenozoic and Archean examples of such putative biocorrosion textures and conclude that microbial origin remains the best explanation for the textures described previously in these Paleoarchean rocks (e.g., >3.4 Ga).

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Oldest fossils controversy resolved

New analysis of world-famous 3.46 billion-year-old rocks by researchers from the University of Bristol, the University of Oxford and UWA (the University of Western Australia) is set to finally resolve a long running evolutionary controversy.
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Early life hunt inspired by oldest fossils debate

A team from Oxford University, the University of Bristol, and the University of Western Australia has analysed 3.46 billion-year-old rocks containing structures once thought to be Earths oldest microfossils. The team present high-spatial resolution data that show these 'Apex chert microfossils' do not match younger fossils of microscopic life and instead comprise peculiarly-shaped minerals.
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Chinese scientists have discovered a 600 million-year-old sponge-like fossil, predating existing findings of primitive animals by 60 million years.
The Nanjing Institute of Geology and Paleontology at the Chinese Academy of Sciences on Monday said that the tiny fossil, which only measures two to three cubic millimeters, was discovered in the Weng'an biota in the southwest province of Guizhou.

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Coated droplets hint at formation of early cells

Researchers at the University of Bristol have designed a chemical system that brings together alternative ideas on how primitive cells were formed on the early Earth to produce a new model of protocell organization. The work is described in an article published this week in Nature Chemistry.
The most fundamental requirement for the emergence of cells on the early Earth is the existence of a closed compartment, but how this came about remains a mystery.

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Theory on origin of animals challenged: Animals need only extremely little oxygen

One of science's strongest dogmas is that complex life on Earth could only evolve when oxygen levels in the atmosphere rose to close to modern levels. But now studies of a small sea sponge fished out of a Danish Fjord shows that complex life does not need high levels of oxygen in order to live and grow.
The origin of complex life is one of science's greatest mysteries. How could the first small primitive cells evolve into the diversity of advanced life forms that exists on Earth today? The explanation in all textbooks is: Oxygen. Complex life evolved because the atmospheric levels of oxygen began to rise app. 630 - 635 million years ago.
However new studies of a common sea sponge from Kerteminde Fjord in Denmark shows that this explanation needs to be reconsidered. The sponge studies show that animals can live and grow even with very limited oxygen supplies.

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3 billion-year-old microfossils include plankton

Spindle-shaped inclusions in 3 billion-year-old rocks are microfossils of plankton that probably inhabited the oceans around the globe during that time, according to an international team of researchers.
The researchers not only showed that these inclusions in the rocks were biological in origin, but also that they were likely planktonic autotrophs -- free-floating, tiny ocean organisms that produce energy from their environment.

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Early feast clue to smell of ancient Earth

Tiny 1,900 million-year-old fossils from rocks around Lake Superior, Canada, give the first ever snapshot of organisms eating each other and suggest what the ancient Earth would have smelled like.
The fossils, preserved in Gunflint chert, capture ancient microbes in the act of feasting on a cyanobacterium-like fossil called Gunflintia - with the perforated sheaths of Gunflintia being the discarded leftovers of this early meal.

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Planet's oldest fossils found in Pilbara, experts say

Scientists analysing Australian rocks have discovered traces of bacteria that lived a record-breaking 3.49 billion years ago, a mere billion years after Earth formed. If the find withstands the scrutiny that inevitably faces claims of fossils this old, it could move scientists one step closer to understanding the first chapters of life on Earth. The discovery could also spur the search for ancient life on other planets.
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