Viruses may not only be found on Earth but could exist in ecosystems holding life in other parts of the universe, The Guardian reported, citing a scientist.
Professor Paul Davies, an astrobiologist, cosmologist and director of the Beyond Center for Fundamental Concepts in Science at Arizona State University, said that the model humankind applies to aliens ranges from microbial life to super advanced civilizations trying to contact us.
This aligns the idea that a wide range of microorganisms would probably support life, whatever form it takes, with viruses being a part of the equation, according to The Guardian.
“Viruses actually form part of the web of life,” said Davies to the news publication. “I would expect that if you’ve got microbial life on another planet, you’re bound to have – if it’s going to be sustainable and sustained – the full complexity and robustness that will go with being able to exchange genetic information.”
Viruses can be thought of as mobile, genetic elements, and research indicates genetic material from viruses has been incorporated into the genomes of humans and other animals by a process known as horizontal gene transfer.
“A friend of mine thinks most, but certainly a significant fraction, of the human genome is actually of viral origin,” Davies was quoted as saying.
According to the scientist, while the importance of microbes to life is well known, the role of viruses is less widely appreciated.
But he said if there is cellular life on other worlds, viruses or something similar, would probably exist to transfer genetic information between them.
What’s more, he said, it is unlikely alien life would be homogenous.
“I don’t think it’s a matter that you go to some other planet, and there will just be you one type of microbe and it’s perfectly happy. I think it’s got to be a whole ecosystem,” the Guardian reported him as saying.
While the thought of extraterrestrial viruses may seem alarming, Davies suggests there is no need for humans to panic.
“The dangerous viruses are those that are very closely adapted to their hosts,” he said. “If there is a truly alien virus, then chances are it wouldn’t be remotely dangerous.”
Research conducted by scientists from the University of Cambridge suggested that signs of life may be detected beyond our solar system within two to three years.
But the need to consider entire ecosystems does not only apply when considering alien life.
“Most people think about, well, we would need to have very large spacecraft, and then sort of recycle things for the very long journey, and then all the technology you’d need to take,” he said.
“Actually, the toughest part of this problem is what would be the microbiology that you’d have to take – it’s no good just taking a few pigs and potatoes and things like that and hoping when you get to the other end it’ll all be wonderful and self-sustainable.”
Davies noted that not all viruses are bad, and are in fact mostly good, he said.
Among their positive roles, phages are viruses that infect bacteria helping to keep their populations in check, he said. Many viruses are also linked to a host of other important processes, including helping plants survive in extremely hot soils, and influencing biogeochemical cycles.
There is also a scientific argument that a significant fraction of the human genome may be remnants of ancient viruses, The Guardian reported.
“We hear about the microbiome inside us, and there’s a planetary microbiome,” said Davies. But he argues there is also a human and planetary virome, with viruses playing a fundamental role in nature.
“I think without viruses, there may be no sustained life on planet Earth,” he said.