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Early Life, Science, and Wrestling Palaeontologia Electronica http://palaeo-electronica.org EARLY LIFE, SCIENCE, AND WRESTLING Stefan Bengtson The road to wisdom? – Well, it’s plain fossilized signatures of life correctly. The and simple to express: fact that most natural entities, life not least, Err and err have fuzzy boundaries is commonly and err again ignored or denied, because words, the but less tools of our thoughts and communication, and less seem so crisp. Either a thing is a fossil and less organism or it isn’t, isn’t it? Either a thing Piet Hein was living or it wasn’t, wasn’t it? The sim- To someone who has been reading ple fact, however, is that right at the the recent media reports, the foundations boundaries of life, at its very beginning of palaeontology and astrobiology would here on Earth, the task to recognize it is seem to be crumbling. The up till now hardest of all and demands the utmost of widely accepted geochemical and palae- our skill and imagination – and humility. ontological evidences for the earliest life Let’s not worry for the moment about on Earth (Schopf 1993; Mojzsis et al. where the correct, or best, answers lie in 1996) have been thrown into serious this ongoing debate, but rather a little doubt (Brasier et al. 2002; Fedo and about how the scientific process is por- Whitehouse 2002; Zuilen et al. 2002). The trayed in the media, and how that influ- issue is of paramount importance for our ences us as scientists. The open-ended understanding of life on Earth and beyond: nature of the scientific inquiry is its most The apparent establishment of life on important characteristic. This is a much Earth as soon as environmental conditions more crucial piece of knowledge in a mod- allowed it some 3.85 Ga ago, and the ern society than any single scientific dis- appearance of microbial fossils soon covery. But it’s a difficult one to grasp, for thereafter (well, about 400 million years its message of "there is no absolute cer- later), have suggested to us that life is tainty" is confusingly similar to "there is no somehow built into the fabric of the uni- absolute truth". The latter is a recipe for verse and will start evolving as soon as "anything goes"; the former describes sci- conditions are right. If our basic presump- ence. tion is wrong, the possibility of finding life In retrospect, it’s often easy to see elsewhere in the universe suddenly which ideas were right and which were becomes bleaker. wrong. When matters are developing, it’s It would seem as though in this most not so easy. Furthermore, "wrong" ideas important of contexts paleontology has sometimes lead to good science. Just one failed its most basic task: to identify the example: The hypothesis of spontaneous Bengtson, Stefan, 2002. EARLY LIFE, SCIENCE, AND WRESTLING. Palaeontologia Electronica, vol. 5, issue 1, editorial 4: 3pp., 96KB; http://palaeo-electronica.org. BENGTSON, STEFAN: EARLY LIFE, SCIENCE, AND WRESTLING generation of life has many times been to the principle that science is an open- shown to be inadequate, but it has proba- ended search, that the value of a hypothe- bly inspired more good science than most sis lies in whether it can help to advance "correct" hypotheses – just think of knowledge rather than being in an abso- Francesco Redi, Louis Pasteur, and John lute sense true. Above all, we take pride in Tyndall. Today, the hypothesis isn’t dead, our ability to learn through error. At the but it has moved to the Archean stage, same time we know that scientists – like where it continues to generate good all creative people – have egos, often big research. Only the future will tell us ones. But unlike art (where the products whether in the end the hypothesis will be are, by definition, artificial), scientific prod- as inadequate to explain the origin of life ucts concern themselves with facts and on Earth as it was to account for the histories about which there is ultimately appearance of maggots in flesh or infuso- only one "right" answer. When a prominent rians in water. But even if that turns out to scientist’s prominent interpretation of an be the case, the hypothesis will have con- object is falsified, some personal damage tinued to stimulate good research. It’s thus is all but inevitable. So, science is a a good hypothesis. Had it been just a nutty human endeavor, run by humans for idea, few would have bothered to refute it. humans. No change there, then. The world is full of nutty ideas, most of Nevertheless, a healthy scientific cul- which are not even worth refuting, but we ture shouldn’t encourage itself or the gen- shouldn’t be afraid of nut-flavored scien- eral public to focus on the egotistical tific hypotheses as long as they are in aspects of the process. Certainly, it should some way testable. Even if "wrong", they foster honest and careful work (there is no may teach us something. inherent value in making errors), but it Life isn’t fair. A palaeontologist who should also encourage retractions from misidentifies a clam for a coral may be earlier held positions when they lead into a temporarily embarrassed but isn’t likely to cul-de-sac. A cornerstone of such a cul- suffer any career damage only for that ture is prestige-less dialogue. Do we have blunder. Only his or her peers will know, such a culture? Maybe, but when one of and will likely shrug it off, knowing that the flagships of science suddenly looks they may goof someday too. One who more like a tabloid picked up at a super- mistakes an a biologically formed structure market checkout counter, it’s time to real- for the world’s oldest fossil is in deeper ize that such a culture has to be nurtured trouble, however much more difficult that in order to survive. task is, if only because the action takes So finally to the point. What prompts place in the limelight. Colleagues will turn this diatribe is Rex Dalton’s (2002) recent on him or her. The same media that have news feature in Nature on the arguments hyped the discovery in the first place will between Bill Schopf and Martin Brasier be quick to pooh-pooh it now. regarding the alleged earliest fossils on In a way, there’s a fair balance here: Earth. I don’t read wrestling magazines, The greater the rewards for success, the but I figure their readers would be comfort- greater the punishment for failure. A scien- able with this portrayal of a scientific dis- tist should enter that mined territory with pute as a heavy-weight match, where one eyes wide open. But fame and shame is of the combatants is painted as a righ- not what good science is made of, or teous if haughty knight, and the other as a should be made of. We all pay lip service scoundrel who has been able to fool the 2 BENGTSON, STEFAN: EARLY LIFE, SCIENCE, AND WRESTLING world for too long. No matter that the ness, but as scientists we should be much "scoundrel" has probably done more to more concerned with the science than with advance the science of Precambrian pale- the splatter entertainment. Besides, good obiology as a multidisciplinary endeavor science is much more fun – and much than anybody else – down with him! more honest – than media-manufactured It’s disheartening to read such a yarn wrestling matches. in a journal dedicated to the advancement of science. Yet we cannot just blame sci- ACKNOWLEDGEMENT ence journalists for the shortcomings of Thanks to Norm MacLeod for useful the scientific culture. It’s each and every- comments. one’s responsibility to help keep it sound. Indeed, we should blow the whistle at vil- REFERENCES lains who forge or steal results. But being Brasier, M.D., Green, O.R., Jephcoat, A.P., Kleppe, A.K., right or wrong in science is not a matter of Van Kranendonk, M.J., Lindsay, J.F., Steele, A. & heroes and villains, and shouldn’t be con- Grassineau, N.V. 2002. Questioning the evidence for Earth’s oldest fossils. Nature, 416:76–81. strued as such. Instead, we should foster Dalton, R. 2002. Squaring up over ancient life. Nature, an atmosphere where we can deal con- 417:782–784. structively with conflicting interpretations. Fedo, C.M. & Whitehouse, M.J. 2002. Metasomatic ori- In a good atmosphere there is an open gin of quartz-pyroxene rock, Akilia, Greenland, and implications for Earth’s earliest life. Science scientific discussion, where ideas are 296:1448–1452. tested against each other and against Mojzsis, S.J., Arrhenius, G., McKeegan, K.D., Harrison, observations in a spirit of mutual coopera- T.M., Nutman, A.P. & Friend, C.R.L. 1996. Evidence tion and collaborative search for the best for life on Earth before 3,800 million years ago. Nature, 384:55–59. available interpretation. In a foul atmo- Schopf, J.W. 1993. Microfossils of the Early Archean sphere, the proponents of the respective Apex Chert: New evidence of the antiquity of life. Sci- ideas punch each other to pulp in a wres- ence, 260:640–646. Zuilen, M.A. van, Lepland, A. & Arrhenius, G. 2002. tling ring before a cheering audience. If Reassessing the evidence for the earliest traces of they want to do it anyway, that’s their busi- life. Nature, 418:627–630. Copyright: Palaeontologia Electronica, 30 August 2002 http://palaeo-electronica.org 3.
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