Posted: Oct 20, 2014 4:29 pm
Zadocfish2 wrote:Also, you are not going to find a civilization of tiny, inch high technologically advanced aliens. Brain size is gong to be a limiter on how small vs how intelligent a species can get regardless of environment. Physics is still the same everywhere.
Physics do form a limit to the intellectual capacity of our animals, but again you assume that life elsewhere would follow the same rules of biology.
If they don't, can you explain how that would work when they're assuredly following the same laws of chemistry.
Zadocfish2 wrote:Perhaps they would have developed a more efficient method to transfer information between what would for them constitute cells, for example.
Even cells have hard limitations on the size they can be due to the component parts, requisite surface area to perform functions etc.
Zadocfish2 wrote:More directly, the very idea that they would have a recognizable form of "brain" is remote; while our animals certainly do, our animals might not set the standard of the entire universe.
You have to understand that the term 'brain' can be used to encompass any substrate where the nerve endings are gathered - the core nervous system. It's entirely possible, as with the octopus, to have distributed brain cells but we don't consider their appendages to be brains because they don't all conglomerate there.
Zadocfish2 wrote:That's how life was best set to develop under our circumstances, but the circumstances on other planets are radically different, and would result in radically different body forms and survival adaptations.
Of course the circumstances are different, but the laws of physics aren't. There are hard limitations on morphology due to universal physical properties. The band of possibility still offers unimaginable diversity, but not simply 'anything'.
Zadocfish2 wrote:Let's not forget, it's not just selective pressures that would change, but the base that those pressures would have built on; not just the results, but every step since the formation of what could be called "life" would have been completely different.
Well, I'd say that the base would be reasonably similar, even if entirely different chemistry was at work. The only way i could imagine truly different fundamental properties being possible is if another building block than carbon was used - perhaps silicon.
Zadocfish2 wrote:It isn't physics that caused the multicellular groups that eventually resulted in complex life to develop ganglia and then brains; that was what was useful for ferrying information. What would or would not be useful to a Martian surviving would be different. Different paths would be taken.
Actually, physics was almost certainly a part of it. How do you judge which way you're going without sensing the physical properties of the world around you? What do 'senses' even mean if not to process external information internally? The senses, nerve endings, ganglia and ultimately brains are all dependent on the physical properties they inhabit, and a significant part of their function is based on being able to perceive and navigate those properties.
Zadocfish2 wrote:As for whether or not we would call them intelligent, that remains to be seen. Even if there is life on Mars capable of forming "ruins", it could well just be the result of some sort of mindless animal from our perspective. It's all speculation, though, and as of now there is no reason to think that there might be life on Mars... but hey, here's hoping.
There's no evidence for ruins on Mars, nor much of life on Mars, not of animals, and certainly not of the kind of complex societies which would produce material culture. The kind of life we're hoping to encounter on Mars would be bacterial - actually, the most prolific building life form we know of considering they're effectively chemical processing factories - but ruins? No.