Dr Kipling Makes Exceedingly Good Hypotheses, Perhaps

Scientists Attempt to Produce Two Identical Snowflakes- Not There Yet Fellas 

I've written about the Drake equation previously. This simple equation attempts to estimate the number of extraterrestrial civilisations in the galaxy. Dr Drake proposed his famous equation during a coffee break at a conference in 1961. To be fair to Dr Drake, his off-the-cuff formula was not designed to be taken too seriously. His hastily framed equation was meant to stimulate discussion concerning the possibility of advanced alien life within our Milky Way galaxy. The equation, as originally proposed, contained nine terms, and at the time, seven of the terms were unknown. Therefore, depending on input data, it was possible to generate a vast range of possibilities. As a serious equation of scientific merit, it was not. However, in the public mind, it has taken on a significance way above its original intention. The general public should hold its head in shame. Dr Drake has been exonerated. ,  

Most Astrophycists, and scientists in general, consider that due to the presence of billions of stars within our galaxy and the appreciation that most host orbiting planets, it is almost inevitable that there are intelligent technological civilisations 'out there'. The number of civilisations is open to speculation, but generally, most pundits place the number in the thousands or millions. To suggest that we might be alone in a cold, insentient universe is akin to heresy, a display of arrogance and hubris by feeble-minded insular humans. With all that said, it cannot be denied that we have absolutely no credible evidence for the existence of any extraterrestrial civilisation in our galaxy. Speculation and hypotheses are fine, but for knowledge to progress, we need data, and currently, that is sadly lacking.    

A British Astrophysicist, Dr David Kipling, has decided to look at the problem from a different angle. What follows is taken from his seminal paper: 'An Objective Bayesian Analysis of Life’s Early Start and Our Late Arrival' published on an open access platform: PNAS. May 18, 2020, 17 (22) 11995-12003. After reading through the paper, I have to admit that the general reader may be put off by the mathematical treatment of the problem and the technical jargon employed. I will endeavour to summarise the paper and present its key elements and conclusions without emphasising the mathematical/statistical notation present in the original paper. This, hopefully, will aid clarity as I suspect most readers are unlikely to be aware of Bayesian statistics and some of the 'mathematical niceties' proceeding from the analysis. On occasion, the paper lapses into pure logic and, therefore, has no appeal to most. Frankly, I am not equipped with the high level of statistical education necessary to fully appreciate the chain of reasoning provided in the paper. However, I am familiar with Bayesian statistics as I've used the technique to calculate genetic risk in patients. A brief digression is in order.

In my professional experience, the technique was useful for calculating the risk of an individual having a particular genetic disorder based on prior 'risk' knowledge. Risk may be updated as new data becomes available. This technique is applicable to conditions that do not conform to classical simple genetic inheritance and is relevant to polygenic conditions where a number of genes represent risk factors or modifiers. A good example of such a condition is schizophrenia or cancer. Back to the paper. 

Initially, the paper deals with setting the time parameters regarding the 'First Emergence of Life' and the advent of the 'Intelligent Observer' The analysis specifically relates to Earth's condition and represents a hypothetical rerun from the conception of life and its appreciation due to the emergence of the 'Intelligent Observer'. By subjecting various time parameters to Bayesian analysis, it is hoped that the results will shed light on the statistical probability of life's inception and the subsequent evolution of intelligent organisms. This analysis may be further extrapolated and applied to other planetary systems within our galaxy and provide a degree of statistical validity for the presence or absence of extraterrestrial civilisations.

Findings and Conclusions

Different models are compared while admitting that the true timing for life's emergence is controversial, with estimates varying wildly. Even taking into account the difficulties in determining the correct time scale, a rerun utilising a variety of time parameters was remarkably consistent in predicting life's early start in Earth's history. As soon as conditions became stable and conducive to supporting life, biogenesis became almost inevitable.    

Earth came into being 4.5 billion years ago, and life has been detected in the fossil record dating back to  3.5 billion years ago. Although these organisms were simple prokaryotes, they were capable of complex metabolic processes, indicating that they had evolutionary antecedents. Thus, life's inception through abiogenesis occurred (origin of life) millions of years previously. Admittedly, this 'first life' and its preceding proto-life have left no mark within the fossil record. This negative observation does not negate their original existence. Given the right conditions, the inception of life is likely a rapid process. The other observation made is that the evolution of intelligence seems to appear late in Earth's development, suggesting that is not an inevitable phenomenon. The implication is that if Earth's 'time clock' was reset, the formation of life would be virtually inevitable. However, the evolution of an intelligent species able to harness technology is less certain. 

Commentary

What are we to make of this analysis? Dr. Kipling's statistical approach to the problem is undoubtedly interesting and novel. The main takeaway notion to be absorbed is perhaps we should not expect our galaxy to be teeming with extraterrestrial advanced civilisations. Simple life may be common, as biogenesis is highly likely to occur, but there are a number of important evolutionary steps that are crucial for the eventual development of intelligent agents capable of self-reflection and the building of rocket ships. It is sobering to contemplate that while life dates back 4 billion years, the first important step toward intelligence, the evolution to eukaryotes, had to await a further 2 billion years. This was a crucial step in the evolution of more complex multicellular organisms. Additional evolutionary steps required to achieve humanity were numerous and complex- well worthy of a future post (maybe).   

Intuitively, given the vast size of the galaxy and its contents therein, it is natural to assume there must be others 'out there' very much like us. But perhaps we really are special and mayhap unique. Dr Kipling, in a podcast, introduces the analogy of the snowflake. Each snowflake is structured so that its form is unique; no two snowflakes are alike, and the chance that this can occur is 1, followed by 768 zeros. In other words, essentially zero.   

Dr Kipling introduces a compelling approach to the great existential question: 'Are we really alone?' This approach is fascinating but suffers from the limitation of all approaches to this question—the lack of input data. Dr Kipling focuses on the only two parameters available to him: the 'emergence of life' and the emergence of the 'intelligent observer'. As with any mathematical technique, the quality and the quantity of the input data are crucial for the calculation of credible results. A reliance on just a single parameter (time) severely limits what can be achieved, especially when we are trying to extend the analysis to a different case, i.e. aliens. Notwithstanding the limitations of this approach, the good doctor demands applause for innovative critical thinking and introduces the reader to an alternative and thought-provoking narrative.