The most recent discoveries are about signs of life in hot springs that are old 3.48 billion-year. These hot springs are placed in Western Australia’s region called Pilbara. The discovery may produce many debates on the first signs of life on Earth, and where they truly appeared. It can also influence in our thoughts and plans on looking for a proper place for life on Mars.
Darwin’s approach to life and its beginning is basically a little and warm pond. But during the last years the most similar locations to this pond, the volcanic hot spring’s ‘edges’ are replaced by the ocean floor’s openings in which flows rich mineral water. These two theories and their competition may end up by creating our decision on where and how to look for further life on Earth and beyond. Moreover, Mars is well known to have had own hot springs in the past; whereas, hydrothermal vents probably exist on Enceladus and Europa.
The evidence of life at hot springs we have was old 400 years, so as this theory is afflicted. But, the marine fossils and the molecular clocks had shown that life is around 4 billion years old. We are also familiar with the fact that nor plants or the animals could get onto the land until a little while back. This had shown the existence of microbes in earthly locations even 2.7-2.9 billion years ago. This fact too, developed a great confusion of whether the origins of life were actually encircled by land. Thinking of the life and its moving from ocean to land for around billion years, it is more understandable than moving from the land pools.
Tara Djokic is a PhD student from the University of New South Wales who announced the univocal, earthly rocks which are old 3.5 billion years, actually contain life. This moves the debate to another place. Her argument and interpretation does not state that life began exactly in hot springs, but her announcement to IFLScience reduces the suspicions on that idea.
The conclusion of the origins of life on Earth may never be disposed, but we should know that space is another dimension. Even though so far, every mission to Mars was considered to find or hopefully produced more specific information about finding life, Mars 2020 rover is seeking more straight forward. The locations which are believed to have life origins shrink slowly, and Djokic states that only one of the three locations, the Columbia Hills, on which Spirit landed, has hot spring’s leftovers.
Djokic believes that her discovery may lead to a drastic turn of events, in which Columbia Hills will contribute, saying that, if it is believed that life once existed in hot springs in the history of Earth, then, it is very likely to be found in hot springs on Mars, too. Moreover, if the fact the life on Earth once began in hot springs, then, the missions which are directly studying the Solar System and its moons may be a waste of time, due to the layers of ice that hide the ocean and the hydrothermal vents.
The springs studied by Djokic took place above the ground. They weren’t placed in the deeper part of the ocean, containing geyserites, which is a mineral that is rare to find in environments with fresh water. This mineral forms when fluids rich with silica meet water. Djokic couldn’t find geyserites older than 400 million years. She explained to IFLScience the existence of this huge gap in the fossil record, but she also stated that the nature of the volcano’s environments is inconstant, in which, many of the older locations probably had been destroyed in many eruptions within the years.
The discovery of this old geyserite is very interesting. But finding stromatolites inside the old springs is main reason for Djokic’s work to be published in Nature Communications. Stromatolites are microbes, or forms of fossils that, speaking of this issue, are no less than the oldest evidence of life. The rocks also contained well-protected bubbles as signals of microbes. The co-author, Professor Martin Van Kranendonk said that these microbes show the existing of life in fresh water and on land, a long time ago.
The things that Djokic discovered look much like other fossils that we have already seen before; she explained that the textures of the rocks and the bubbles within, look more like the modern springs than the ones from the ancient places. She also stated that, even though we don’t know much about the microbes that provoked many questions, a mix of life-forms that live from the sunlight and from the energy from the springs, exist.
Source > iflscience.com