Hacker News new | past | comments | ask | show | jobs | submit login

Unless there was a common source like some sort of panspermia event, there is no reason to assume aliens would also use DNA/RNA to encode information.



Why not? The only thing you need to prove is that this is the most energy advantageous process for the common components of life that produces a reliable and durable self replication. The amino acids might be different but even there it’s only physics there are only so many likely permutations.

And as far as intelligent (technological intelligence) biological life it’s more likely than not to be far more similar to us than completely alien.

It would have to develop on land or at least be able to transition to land at some point. Can’t have complex chemistry under water, can’t have fire can’t have metallurgy.

Vision in a spectrum similar to us or higher is pretty much a must, both as a requirement for higher brain development as well as to actually be exposed to all that information. A star fairing civilization that can’t see stars isn’t likely to develop and as far as odd spectrums go RF and Xray might be able to see stars but not predators so it unlikely to develop in the first place.

Appendages that allow fine tool development is pretty much a must for incremental technological development also.

Gravity at least at the upper bounds would need at minimum to obey the rocket equation any world with heavier gravity than that would allow that wouldn’t likely to produce a space fairing civilization.

Lower limits might be imposed on powered flight and missile weapons that may be a required developmental phase also.

And as far as planetary makeup goes then again should be rather similar including likely evolutionary phases that would produce large fossil fuel deposits.

Atmospheric oxygen is also a must no oxygen no fire.

As for as other elements enough metals to support a technological civilization as well as possibly enough fissile material for at least a partial nuclear phase tho lack of fissile material might put developmental pressure on the fusion part of the tech tree so there is some wiggle room.


Your argument makes interesting observations, but relies on Earth-centric assumptions. For instance, the requirement for land-based development of complex chemistry and metallurgy assumes there couldn't be alternative pathways in different environments. We already see complex chemistry happening in deep-sea hydrothermal vents that challenges our assumptions about where complex processes can occur.

Similarly, the needs for human-like vision or specific tool manipulation may be limiting our analysis. Consider how bats and dolphins build sophisticated mental models of their world through echolocation, or how octopodes demonstrate problem-solving abilities with fundamentally different appendages than ours.

Given we only have one example of technological civilization, we should be cautious about declaring which features are truly universal requirements versus those that just happened to work for us. There might be paths to advanced technology that we haven't yet conceived.


Octopuses or octopodes.


thank you!




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: