We can predict that aliens exist, if aliens exist


I am informed that Oxford biologists have outlined what alien life would look like — I’m a bit put off by the title. One of those things that reduces the credibility of a story for me is when the editor feels the need to pump up the authority by prefixing “biologist” with the name of a prestigious university. Wouldn’t just “biologists have outlined what alien life would look like” been adequate?

I went ahead and read the source paper in the International Journal of Astrobiology, “Darwin’s Aliens”, and you know, I’m not very impressed. It claims in the abstract that “we can make specific predictions about the biological makeup of complex aliens,” but it doesn’t — it makes vague, amorphous generalities about possible aliens. Basically, it says that there would be replicators of some sort that would use natural selection, and then it announces that there would have been “major transitions” in their evolutionary history to generate complexity.

Uh, OK.

Picture an alien. If what you are picturing is a simple replicating molecule, then this ‘alien’ might not undergo natural selection. For example, it could replicate itself perfectly every time, and thus there would be no variation, and it would never improve. Or it might have such a high error rate in replication that it quickly deteriorates. If we count things like that as life, then there could be aliens that do not undergo natural selection. But if you are picturing anything more complex or purposeful than a simple molecule, then the alien you are picturing has undergone natural selection. This is the kind of prediction that theory can make. Given heredity, variation and differential success, aliens will undergo natural selection. Or, more interestingly, without those three things, aliens could not be more complicated than a replicating molecule. Given an adapted alien, one with an appearance of design or purpose, it will have undergone natural selection.

The telling phrase in there is this one:

This is the kind of prediction that theory can make. Given heredity, variation and differential success, aliens will undergo natural selection.

I agree. That’s the kind of prediction you can make. It’s kind of…broad, don’t you think?

Then they toss in their edifying zinger.

In particular, the evolution of complex life on the Earth appears to have depended upon a small number of what have been termed major evolutionary transitions in individuality. In each transition, a group of individuals that could previously replicate independently cooperate to form a new, more complex life form or higher level organism. For example, genes cooperated to form genomes, different single-celled organisms formed the eukaryotic cell, cells cooperated to form multicellular organisms, and multicellular organisms formed eusocial societies.

Who would have guessed? Complex organisms must have experienced increases in complexity in their evolutionary history.

You want another tautology?

Once again, picture an alien. If you are picturing something like unlinked replicating molecules or undifferentiated blobs of slime, then your aliens might not have undergone major transitions. But if what you are picturing has different parts with specialized functions, then your alien is likely to have undergone major transitions. What matters is not that we call them ‘major transitions’, but rather that complexity requires multiple parts of an organism striving to the same purpose, and that theory predicts that this requires restrictive conditions. Consequently, if we find complex organisms, we can make predictions about what they will be like.

If we find complex organisms, then we can predict what they will be like. You keep using that word, “predict”. I don’t think it means what you think it means.

Now we get an illustrative illustration of what an alien might look like.

Major transitions in space: ‘The Octomite’. A complex alien that comprises a hierarchy of entities, where each lower-level collection of entities has aligned evolutionary interests such that conflict is effectively eliminated. These entities engage in a division of labour, with various parts specializing on various tasks, such that the parts are mutually dependent.

Why? The authors seem to think that they can therefore predict that aliens will consist of a literal hierarchy of complexity, with literal morphological layers. I ask you, is there anything on Earth that looks like this? Then their model fails to predict any of the forms found on the one known planet with complex life, and is therefore rather pointless.

They have a summary of their method for making predictions.

When using evolutionary theory to make predictions about extraterrestrial life, it is important to avoid circularity. Our chain of argument is: (1) Extraterrestrial life will have undergone natural selection. (2) Knowing that aliens undergo natural selection, we can make further predictions about their biology, based on the theory of natural selection. In particular, we can say something about complex aliens – that they will likely have undergone major transitions. (3) Theory tells us that restrictive conditions, which eliminate conflict, are required for major transitions. (4) Consequently, complex aliens will be composed of a nested hierarchy of entities, with the conditions required to eliminate conflict at each of those levels.

I feel like I should remind you all that in their abstract, they say “we can make specific predictions about the biological makeup of complex aliens.” Those aren’t specific predictions. I don’t see how those generalities are at all useful in the task they’ve set themselves.

Also, nowhere in their model do they take into account the confounding variable of chance — it’s as if all they have to do is invoke natural selection and then the history of the species unfolds. Which it doesn’t.

Maybe that’s the point of highlighting the authors’ university — it’s supposed to make us overlook the bullshit.

Comments

  1. chigau (違う) says

    Maybe that’s the point of highlighting the authors’ university — it’s supposed to make us overlook the bullshit.

    Remember harvardmba?

  2. birgerjohansson says

    …and here is an alternative lineage from our own planet, this example (see image) is from the early Cretaceous.

    Mammal-like reptile survived much longer than thought https://phys.org/news/2016-04-mammal-like-reptile-survived-longer-thought.html
    (The image depicts an animal covered in hair, but hair may have evolved after the true mammals split off. Although this lineage could have evolved hair or other insulating structures independently, the way therpod dinosaurs did (feathers) or pterodactyls (hair), the image should be taken with a grain of salt.)

  3. Artor says

    Octomite looks a bit like a tardigrade crossed with an Old One. These geniuses never considered UN-natural selection, did they?

  4. says

    So… that looks a LOT like an alien in Brightness Reef by David Brin. A set of rings that looslely communicate with each other. They were uplifted by another group of aliens with the addition of a “Master Ring” that brought all the others into line.

    Interesting books. Not a new idea though.

  5. willj says

    My theory, which is mine, is that all brontosauruses are thin at one end, much much thicker in the middle and then thin again at the far end.

  6. birgerjohansson says

    “the confounding variable of chance” -the mammal-like reptile above is in fact a relatively close kin.

    Avians have developed impressive brains (parrots, corvids) even though our closest common ancestor was a *very* primitive stem-amniote, ca 250 million years ago.
    Bony fish with fins that were “pre-adapted” for walking on land came slightly earlier than ray-finned fish, but have since been pushed to marginal niches in the ocean.
    And imagine if cephalopods develop myeline sheathing around their rnerve bundles…

  7. davidnangle says

    It seems to be covered in assholes. Perhaps its form was dictated by its creator, in His metaphorical image.

  8. birgerjohansson says

    willj @ 7, in addition I think most succesful species have their innards on the inside.

  9. chrislawson says

    Well this is pretty embarrassing as a paper, especially when you compare it to Richard Alexander’s 12 predictions for a eusocial vertebrate based on evolutionary principles…which turned out to be a spot-on description of naked mole rats on every one of his twelve points.

    I’m also astonished that the authors think there is such a thing as a perfectly self-replicating molecule, or that they would use as blatantly teleological an argument as “complexity requires multiple parts of an organism striving to the same purpose.”

    I mean, sure, I think we can make predictions about what evolution would create in alien organisms by looking at the evolutionary events that have occurred multiple times independently on Earth. So I would expect any alien ecosystem to include some multicellular organisms. I would expect organisms that move through fluid to evolve hydrodynamic efficiencies. I would expect any light-filled environment to promote the evolution of some equivalent of an eye. And so on. Even so, these predictions rely on an Earth-like environment. If we find life in an exotic (for us!) environment, I think there’s very little we can predict beyond whatever meets our basic definition of life.

  10. =8)-DX says

    Ooo, oo, let me try!
    *coughs*
    Ahem, here we go, I predict:
     • Aliens will have thingies.
     • Some of the thingies will have other thingies on them.
     • Some thingies will have whatsits on them!
     • Some aliens will have so complicated thingies, made up of whatsits and other thingies, that the resulting toodlesplat will be a whatmadinkle!

    Did I do good?
    =8)-DX

  11. chrislawson says

    I should add — those predictions above are predicated on their being sufficient time. If we found a planet that had just arrived at primitive self-replicators a few thousand years ago, then obviously I would expect none of those predictions to hold.

  12. chrislawson says

    birgerjohansson: the god-as-asshole trope is not just old. Going by the Book of Job, it’s original canon.

  13. says

    I should clarify that… every species on an alien planet will look like humans, but with bumpy foreheads. The dominant intelligent species. Their pets. Their food. Predators and prey. The plants. Everything.

  14. Moggie says

    Simon Proctor:

    So… that looks a LOT like an alien in Brightness Reef by David Brin. A set of rings that looslely communicate with each other. They were uplifted by another group of aliens with the addition of a “Master Ring” that brought all the others into line.

    One ring to rule all the other rings, you mean? I wonder where he got that idea?

  15. killyosaur says

    I was thinking that it looks an awful lot like an attempt to create a biological version of the Daleks. Considering these biologists are from Oxford, that might just be the case :P

  16. says

    killosaur:
    I was thinking that it looks an awful lot like an attempt to create a biological version of the Daleks

    Nah, it’s shoggoths.
    Tardigrade shoggoths.

  17. anchor says

    “Maybe that’s the point of highlighting the authors’ university — it’s supposed to make us overlook the bullshit. ”

    Didn’t work.

  18. richardemmanuel says

    I predict dumb aliens won’t get to us. And intelligent aliens won’t get to us. And mediocre aliens will get halfway. ‘Take me to your leader’. Doesn’t sound so plausible these days.

  19. says

    Audible just offered The Mountains of Madness as a daily deal last week, so I was listening to it today, and that thing looks an awful lot like the barrel-shaped starfish creatures.

  20. busterggi says

    “aliens will consist of a literal hierarchy of complexity, with literal morphological layers. I ask you, is there anything on Earth that looks like this? ”

    The hive mind creatures known as churches and/or corporatins?

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