There is a theory that if alien life exists, those organisms will be roughly our size. The reasoning is that you can’t achieve advanced civilisation without fire, and you can’t tend a fire if you’re much smaller or larger than a human.
Not my theory, but an interesting thing to consider
I find that theory fascinating, as well as the one where it would have to be carbon based like us because chemistry. (Silicon a distant second on supporting chemistry that a life form might need)
Then intelligent life would need to be land based because you can’t easily do things requiring heat without an oxygen atmosphere and something to burn (an octopus or porpoise might be intelligent but that’s a dead end without fire)
To be space faring, your planet couldn’t have much more gravity than earth, else chemical rockets wouldn’t work
At what point is it usefully generalizing on what any life form would need vs where are preconceptions limiting your thinking?
There is a theory that if alien life exists, those organisms will be roughly our size. The reasoning is that you can’t achieve advanced civilisation without fire, and you can’t tend a fire if you’re much smaller or larger than a human.
Not my theory, but an interesting thing to consider
I find that theory fascinating, as well as the one where it would have to be carbon based like us because chemistry. (Silicon a distant second on supporting chemistry that a life form might need)
Then intelligent life would need to be land based because you can’t easily do things requiring heat without an oxygen atmosphere and something to burn (an octopus or porpoise might be intelligent but that’s a dead end without fire)
To be space faring, your planet couldn’t have much more gravity than earth, else chemical rockets wouldn’t work
At what point is it usefully generalizing on what any life form would need vs where are preconceptions limiting your thinking?