Guest Post – Life’s Origin: Probable or Improbable?

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The blue marble, NASA

Are we alone in the universe? Is there alien life out there somewhere? These are questions that have long intrigued humankind. Answers have ranged from the optimistic postulate by Frank Drake forty years ago of more than 1,000 civilizations in our galaxy alone to the much more pessimistic opinion of the astrobiologists, Ward and Brownlee, in 2000 that complex life may be extremely rare in the universe at large. Whereas the latter authors contend that intelligent life may be scarce, they express the belief that simple (microbial) life is abundant in the universe.

The likelihood of simple life being widespread depends, of course, on the probability of life’s origin. On this question there is again a wide range of opinion among scientists. Ward and Brownlee believe that life’s origin on Earth was highly probable and microbial life is common in the universe because it occurred so quickly on the geological time scale here on Earth. Life is believed to have appeared on Earth relatively soon after the planet formed and cooled down enough to allow liquid water to exist at a habitable temperature. There is indirect evidence in the form of carbon deposits with C-12 isotopic enrichment attributable to living organisms as long as 3.8 billion years ago, just after the last large series of meteor impacts on the moon and presumably on the Earth as well (see last week’s post). However, not everyone in the scientific community is persuaded that life has a high probability of getting started on any planet, including planet Earth.

Jacques Monod, Nobel laureate in Biology, once likened the origin of life to winning a lottery. He believed this event was very improbable based on the extreme difficulty of explaining it scientifically. He wrote that it was a pure stroke of luck and “our number came up in the Monte Carlo game.” Richard Dawkins once asked the question, “What is the largest single event of sheer naked coincidence, sheer unadulterated miraculous luck that we are allowed to get away with in our theories, and still say that we have a satisfactory explanation of life?”[1]Dawkins’ answer:  “The maximum amount of luck that we are allowed to assume, before we reject a particular theory of the origin of life, has odds of one in N, where N is the number of suitable planets in the universe.”[2]Of course, if the odds are much better than one in N, that would be like buying many tickets in the lottery making it likely that many planets would “win.” But if the opposite is true, then Monod’s analysis is accurate, winning planets would be rare, and obviously we could only be on one of the small number of winners, or maybe the only one.

Most current origin of life scientists are convinced that life has a relatively high probability of appearing on a temperate, rocky planet with abundant water. Their confidence cannot be based on knowledge of the probabilities involved, however, since this would require an understanding of how life got started. At the present time, the origin of life remains one of the great unanswered mysteries of modern science. It can be argued that without a clear scientific explanation of life’s origin from inanimate matter, estimations of the odds for life’s appearance remain extremely uncertain.

Meanwhile other contemporary scientists have suggested that the probability of life’s origin may be miniscule based on our current understanding. For example, physicist Paul Davies opines that “we may be living in a universe that has 1020potential Earth-like planets within the body of space we can see. But 1020is a trifling number compared to the odds against shuffling those molecules into the right formation. If it happened by chance shuffling, we’re it.”[3]Davies remains hopeful that scientists will discover new principles that will help to explain how life emerged from inanimate matter, which would improve the odds. One extreme example of a molecular biologist in the low probability camp is the Russian-born American, Eugene Koonin. He is so pessimistic about the probability of life’s origin that he suggests that the number of planets in the universe is not sufficient to compensate. He therefore resorts to the postulate of a multiverse, proposing that 10500universes may be necessary.[4]

There currently remains no definitive scientific answer to the question of life’s probability. We may well ask, what are the philosophical/theological implications? The difficulty of explaining life’s origin and the accompanying estimates of low probability have led some Christians to bring God into the picture. Design by an intelligent creator is invoked or the special, miraculous intervention by Jehovah is cited as an explanation for what seems to be a miraculous appearance of life. In the former case, design is predicated on the extremely low probabilities for life in some current estimates. When the probabilities are too low to attribute the event to chance, the action of a designer is invoked. In the latter case, God is inserted into the picture where science has failed—a classic “God of the gaps” maneuver. I would argue that neither approach is sound theologically. God is sovereign over all his creation, both the probable and the highly improbable. What may appear to us as a random event with a probability of virtually zero, is still the result of the will of him who upholds the entire universe by his powerful Word.  Our appropriate response is to applaud the efforts of scientists attempting to understand creation, including how life got started on this planet, all the while continuing to give glory to the Creator for the matchless creativity exhibited in this marvelous universe.

[1]Richard Dawkins, The Blind Watchmaker (New York and London: W. W. Norton & Co., 1996), p. 141.

[2]Ibid., p.144.

[3]Paul Davies in Chris Impey,  Talking about Life: Conversations on Astrobiology(Cambridge: Cambridge University Press, 2010), p.352.

[4]Eugene Koonin, The Logic of Chance: The Nature and Origin of Biological Evolution (Upper Saddle River, NJ: FT Press Science, 2011).

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© L Funck

Larry Funck is an Emeritus Professor of Chemistry at Wheaton College where he has taught since 1969. In 1995-96 he served as a Fulbright Fellow at the National University of Lesotho in southern Africa. From 2009 to 2013 he was Chief Reader for the College Board’s Advanced Placement Chemistry program. He currently teaches the origin of life component in the Theories of Origins course at Wheaton and is a co-author with the other faculty of a textbook entitled Understanding Scientific Theories of Origins: Cosmology, Geology, and Biology in Christian Perspective to be published later this year by InterVarsity Press. Married for over fifty years, he enjoys classical music, following major league baseball and learning to know his grandchildren.

Guest Post: Life as old as the Earth? The earliest evidence for living things

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Cross-section of a fossil stromatolite © James St John, flickr, https://creativecommons.org/licenses/by/2.0/

The history of life on Earth is almost as long as the history of Earth itself. The most precise scientific dating methods tell us that our planet formed 4567 million years ago, although there are no rock samples preserved from this ancient and chaotic time. The oldest known Earth materials are about 4300 million years old, and are found in the remote deserts of western Australia. The oldest probable evidence for life on Earth has been dated between 3700 and 3800 million years, in west Greenland, and is so sophisticated that the history of life on earth must extend much further back. These observations suggest that life is a fundamental property of our planet, a feature which makes the Earth very different from its immediate rocky neighbours. Continue reading

How Biofriendly is the Universe?

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Kepler-186f: artist’s concept. Image credit: NASA Ames/JPL-Caltech/T. Pyle

It’s obvious that our own planet is friendly to life, but what about the rest of the universe? Is the rest of space too cold and dark – or hot – to allow life to develop? Was the development of life on earth a hugely improbably event, or pretty much a forgone conclusion? The Nobel Prize-winning biochemist Christian de Duve spent the last few years of his career investigating this question, and came up with a surprising answer. In this post I’ll share five of the characteristics of life that he studied. Continue reading

Rare Earth: Why ‘simple’ life may be common in the universe, but animals may be unique to our planet

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Cropped from: Artist’s impression of a M dwarf star surrounded by planets. Credit: NASA/JPL-Caltech

Anyone who has watched enough nature documentaries will know that life can exist pretty much anywhere on Earth. One episode of the Blue Planet II series showed a hydrothermal vent – a crack in the mid-ocean ridge where hot gases and water pour out. Bacteria thrive in the scalding water around the vents, getting their energy from chemicals like hydrogen and sulphur, and enabling a rich ecosystem of bacteria-eating crabs, shrimps, and other animals to build up to such a density that it rivals Continue reading

Life in a Purposeful Universe?

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Supernova remnant in the Large Magellanic Cloud , by NASA’s Goddard Space Flight Center/Jenny Hottle

What does astronomy have to do with the living world? Is a vast universe really necessary to life? Any does science say anything at all about purpose? In today’s podcast (transcript below) I discussed these questions with astrophysicist Dr Jennifer Wiseman, who shared some of her personal perspectives. Jennifer is a person of faith who has spent time thinking about the questions about meaning and purpose that her work raises. For her, science does not compel belief in God, but it can vastly enrich the sense of a purposeful and awe-inspiring creation. Continue reading

From the Dust: How the universe became fruitful for life

Star cluster. NASA, ESA & E. Sabbi (ESA:STScI) 678125main_hubble_sparkles_full_full
Two clusters of massive stars that may be in the early stages of merging. NASA, ESA & E. Sabbi (ESA/STScI)

How can a universe that seems so cold, dark, and sterile become a place where life can flourish? This is one of the questions that the astronomer Dr Jennifer Wiseman asked in her seminar at the Faraday Institute last month. In her talk, part of which I have summarised here in my own words, she explained why the cosmos can be seen as a very fruitful place – and why this idea is compatible with her own sense of  purpose for the world.

Jennifer grew up on a farm in Arkansas, where she came to know the stars in a way that those of us who have lived in light-polluted cities all our lives could never appreciate. She went Continue reading

Guest Post: God, Bubbles and the Origin of Life

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Bubble by zacktionman. Flickr. (CC BY-NC 2.0)

There is something about the sight of a bubble hanging effortlessly in the air that excites a childlike wonder in us, whatever our age. Perhaps it’s their delicate beauty, almost transparent, glimmering with a rainbow of colours? Perhaps it’s the temptation to pop them? For me, the most amazing thing about bubbles is that they make themselves. Continue reading