Terrestrial life, extinct and past; or alive and present is amazingly diverse – in appearance anyway, but also in the environments they inhabit and the abilities they have to survive and thrive. But under the skin, our fundamental biochemistry, be you T-Rex, or be you a maple tree, or be you a bacteria, or be you, you, well you’re all as closely related as makes no odds. Extraterrestrial life will also be amazingly diverse – in appearance. However, the fundamental biochemistry that makes them, them, might be equally diverse relative to what makes you, you.
Traditional Hollywood fare, when it comes to envisioning aliens, tends to take the cost-friendly option and place actors in strange looking, but humanoid form costumes and associated makeup. Or, forget the costumes, maybe they just give the actors pointed ears or paint a few dots on them or wrinkle their noses! The question remains, will real, as opposed to Hollywood
Continued from yesterday’s blog…
Chemistry: Life-Not-As-We-Know-It: Humanoid, or non-humanoid life forms, with biochemistry very different from ours, is a reasonable rarity in science fiction. When such beings are depicted, they tend to be pure energy entities (fairly easily done via special effects), or something resembling terrestrial life forms albeit given an exotic biochemistry. Star Trek’s Horta are a case in point.
It’s going to be chemistry, not physiology that ultimately dictates life-not-as-we-know-it. Substitute liquid ammonia or ethane for water; silicon for carbon; copper for iron in the blood (Mr. Spock, anyone?), the literature of speculative astrobiology, not to mention the literature of science fiction as well as sci-fi TV series and films are relatively rare of really alien aliens, everything from pure energy beings to solid rock and crystalline life forms, but hardly non-existent. Alas, life-not-as-we-know-it, that is non-CHON (Carbon, Hydrogen, Oxygen & Nitrogen) life has been at best a ‘what if’ scientific and literary speculation of the purest kind. When subjected by biochemical specialists to critical examination, non-CHON biochemistries were found wanting as likely viable alternatives. For example, replacing carbon with silicon would have oxygen breathing aliens exhale not carbon dioxide but silicon dioxide – sand! Translated, we find the devil’s in the biochemical details as it were. While the possibility for alternative biochemistries can not be totally dismissed, we know CHON life can exist, so taking that certainty, we run with that first and foremost, when, in the first instance, looking for ET.
Really Far Out, Star Scout: Dark Life Composed of Dark Matter and Fueled by Dark Energy: However, while on the subject of life-not-as-we-know-it, you’re in for a bit of a surprise.
You are a minority, and it has nothing to do with your sex, age, blood type, religion, racial or ethnic characteristics, I.Q., or any other similar or related thing.
You are a minority, even a rarity, in that all the stuffs (matter and energy) that make you, you, and make you tick, is in itself a minority or a rarity in the cosmos, and it’s not because most of the cosmos is ‘empty’ space (not that in quantum theory space can ever be 100% empty). All that you experience (see, hear, feel, smell and taste) around you, be it from your immediate surrounds out to the farthest reaches of the cosmos is the result of just 4% (or thereabouts) of the ‘stuff’ we know and love – electrons and positrons, protons (composed in turn of quarks) and antiprotons, neutrons (again in turn composed of quarks) and antineutrons, neutrinos and antineutrinos, photons (electromagnetism), the theoretical to date undetected gravitons (gravity), gluons (the strong nuclear force), etc. And 4% of anything represents a minority, even approaches the definition of rarity.
The other 96% (or thereabouts) of the cosmos is made up apparently of both ‘dark matter’ and ‘dark energy’, which isn’t your run of the mill electrons, protons, neutrons, electromagnetism, gravity (although ‘dark matter’ exhibits a positive gravity akin to normal matter.), etc. yet can and does interact with the cosmos and its contents. It’s sort of like having a room full of 100 people, only 96 of them are ghosts, albeit physical enough to interact with the contents of the room (just like real ghosts allegedly do).
One needs to point out that thus far at least, there’s no actual known connection between ‘dark matter’ and ‘dark energy’ apart from the fact that neither is visible to us in the way that a star or light bulb is visible; thus, the common term ‘dark’. Both ‘dark matter’ and ‘dark energy’ have been detected by more indirect means, primarily their influences on the 4% of stuffs we can see.
The subject of astrobiology (as outlined above) deals mainly with the question of finding extraterrestrial life-as-we-know-it. That is, finding life like us based around traditional forms of matter and energy; life with similar chemistry, energy needs, and environmental requirements. However, astrobiologists do like to speculate and cast their minds far and wide and envision possible forms of life that fall in the category of life-not-as-we-know-it; life that makes use of exotic chemistries, unfamiliar energies, and (to us) extremely hostile environments.
So, the question proposed is could a form of ‘dark life’ originate and evolve out of some combination of ‘dark matter’ and/or ‘dark energy’? (This would be an ultimate life-not-as-we-know-it prize for astrobiologists.) Well, since we don’t really know what ‘dark matter’ is – its chemistry and other properties – and since we don’t have a handle on the nature of ‘dark energy’ either, one can’t conclude one way or another at this stage. Let’s just call it a whopping big “maybe”. Perhaps (the late) Sir Fred Hoyle’s Black Cloud concept as expressed in his sci-fi novel of that name, might not have been that far off the mark after all!
The major fly in this ointment is, I suspect, that ‘dark energy’ is a repulsive force, which at first glance, seems incompatible with life of any kind. Thus, for the moment, I’ll include it as a ‘dead end’. However, it’s early speculative days yet and there’s a long way to go before ruling anything either in, or out.
An idle thought however, we wonder what the missing 96% of the Universe is – just calling it ‘dark matter’ and ‘dark energy’ doesn’t tell us what it is. Perhaps a ‘dark energy/matter’ being wonders what the missing 4% of their Universe is composed of!
Further recommended readings:
Barlowe, Wayne Douglas & Summers, Ian; Barlowe’s Guide to Extra-Terrestrials; Methuen of Australia, Sydney; 1980:
Cockell, Charles S.; Impossible Extinction: Natural Catastrophes and the Supremacy of the Microbial World; Cambridge University Press; Cambridge
Friend, Tim; The Third Kingdom : The Untold Story of Archaea and the Future of Biotechnology; Joseph Henry Press, Washington , D.C.
Gates, Evalyn; Einstein’s Telescope: The Hunt for Dark Matter and Dark Energy in the Universe; W.W. Norton & Co., New York
Hooper, Dan; Dark Cosmos: In Search of Our Universe’s Missing Mass and Energy; Smithsonian Books, New York
Huyghe, Patrick; The Field Guide to Extraterrestrials; New English Library, London
Krauss, Lawrence M.; Quintessence: The Mystery of Missing Mass in the Universe; Vintage, London
Siegel, Richard & Suares, Jean-Claude; Alien Creatures; Harper & Row, Sydney and Melbourne; 1978:
Ward, Peter; Life As We Do Not Know It: The NASA Search for (and Synthesis of) Alien Life; Penguin Books, New York
Wharton, David A.; Life at the Limits: Organisms in Extreme Environments; Cambridge University Press, Cambridge
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