The origin of life remains a mystery after 200 years. The Origin of Species Darwin contains a question that could not answer. How did the first living being that gave rise to the species? Biologist eluded post a reply, perhaps for lack of evidence or perhaps because of their religious beliefs. A century later there is still no conclusive evidence, but two opposing schools. One notes that the first life on Earth originated when the planet was young. Others have no doubt that came from space. “It’s 28 times more likely that life originated in space,” said Chandra Wickramasinghe. This astronomer at the University of Cardiff (UK) has argued for decades the theory of panspermia. Affirms that the space is full of cellular life that is trapped inside comets. One of them was shattered when it collided with the atmosphere of the Earth some 3,800 million years. Although most of the bacteria died, a minority survived the trip and launched life on Earth. “The theory now is extraordinary is that seeks to confine the life and evolution to a single planet,” says Wickramasinghe in an article to be published in the International Journal of Astrobiology. In their view, life is a cosmic phenomenon supported by bacteria that float in the space dust. Darwin ventured that life originated in a “hot pond” The hypothesis is supported by studies that have shown that bacteria can withstand extreme conditions similar to those that would live for interstellar travel. Also in other studies that have found basic organic compounds floating in space. Constant phenomenon Wickramasinghe says that panspermia is still happening even today. A few years ago, his team, funded by the Indian space agency, found bacteria at heights of up to 40 kilometers above the ground whose presence was detected with balloons. The study has been discredited by some scientists and Wickramasinghe himself acknowledges that some doubt that their samples were contaminated are difficult to refute. He adds that, given the importance of the discovery, the big agencies like NASA should repeat it soon. “Years ago, talking about panspermia was sufficient to withdraw colleagues salute you,” says the researcher of the CSIC and the Universidad Autonoma de Madrid Ricardo Amils. “Today there are no smiles when you ask this question,” he adds. Amils studying bacteria that live in Rio Tinto (Huelva). The environment in which they live is so extreme that it would be used to investigate how life on Mars. According to the expert, life is much more robust than thought a few years ago and several studies have shown that some organisms are able to survive space travel. The only downside is that panspermia does not end the debate, but it moves, it does not explain how they formed these first bacteria that have come to Earth. Many other experts believe the first spark of life on Earth happened. This is what Darwin suggested in a letter to his friend Joseph Dalton Hooker in 1871. Described in a brief paragraph a warm little pond with ammonia and other chemicals between the light and electricity could generate a reaction that would lead to the first proteins. These compounds would react to more complex forms to cause a primitive protocell. “Darwin was right with the pond, because unlike the ocean, these small deposits can accumulate and dry chemicals, temperature changes and other changes needed for life originates,” says Jack Szostak, a researcher at Harvard University ( USA). His laboratory is one of the most advanced in reproducing chemical reactions that led to the first cell, which could be very different to today. I have managed to assemble cell membranes able to grow and divide. They have also achieved basic genetic material capable of replication, ie, the basic engine of evolution. “We have a protocell able to play after a few years,” says Szostak. “That would explain how emerge Darwin described evolution from the chemical. “Years ago if you were talking about panspermia removed the greeting” While looking for that recipe Szostak primeval guru Craig Venter synthetic biology pursues the opposite course. It involves taking a cutting modern cell genome and go up to the minimum of genes capable of sustaining life. Like panspermia, these lines of research will also lead to a new question. No person shall ensure that the primitive cell is created in a lab like the one that emerged in the Earth some 3,500 million years. “We can never see exactly what happened,” laments Henderson Cleaves, a researcher at the Carnegie Institution for Science, USA. Last year, Cleaves raised another famous theory on the origin of life that had fallen into disgrace. It was based on an experiment with flasks made in 1953 by Stanley Miller to prove that a spark in the early ocean created the first building blocks of life: amino acids, building blocks of proteins. Miller got amino acids, but their assumptions about the early atmosphere that enveloped the earth was wrong. Over 50 years later, Cleaves rescued results from a second experiment Miller had also generated compounds. Instead of an ancient sea, the experiment emulated the conditions of a volcano, where, according to investigators, could have arisen the coveted first cell. “We can never know exactly what happened 3,500 million years ago” Other smaller volcanoes that spit out water from the sea floor are also candidates for having provided the first life. In 2000, the U.S. research ship Atlantis found in mid-Atlantic hydrothermal vent a way previously unknown. It was calcium carbonate towers 50 meters over spitting water at a temperature above the seafloor. Subsequent research in the area, dubbed the Lost City, showed that its interior is a complex network of tiny containers with a cut similar to a tissue. These small compartments were the times of first cells, according to NASA scientist Mike Russell. Receptacles allowing them to concentrate the compounds giving rise to complex molecules and energy to reach the DNA and genes. Again, the hypothesis can not prove that’s what happened, but scientists do not give up on finding more answers about the origin of species. “I am convinced we will get to answer the question,” says Amils. “I do not think anyone can say when, although it is becoming increasingly close,” he concludes.
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