I doubt this, as it was in reference to whether we should attempt to contact extraterrestrial species.
If they’re looting entire systems, why would it matter whether we contacted them or not?
If they’re specifically looting biosphere planets…why?
Jupiter has thousands of earth masses of hydrogen. Surely this would be a better planet to refuel at.
Watch the skies for the Yacatisma!
SETI hasn’t noticed anything so either we aren’t looking hard enough or we live ina quiet universe and life is much rarer than we think.
Ohh space vampires.
Agreed.
Illnesses have trouble going from human to horse, i don’t see how it goes from human to martian very easily.
We hardly seem worth the effort of enslavement.
If you can travel light years to gather resources I don’t see why you need to gather contested resources.
Self replicating robots. the universe is filled with self replicating robots from extinct civilizations.
I could be that life is very common, but intelligent life is rare. Consider: If we visit another life-bearing planet, we are seeing only a momentary snapshot of its biosphere’s evolutionary history. In Earth’s case, that history goes back at least 2 billion years; and there were no intelligent lifeforms here at all, as far as we know, until the first hominids emerged a geological eyeblink ago. It could be that a life-bearing planet orbiting Tau Ceti is all set to produce intelligent beings a geological eyeblink from now, which is still a longer period than the entire existence of Homo sapiens to date. It could also be that planet had intelligent beings a geological eyeblink ago, but they went extinct while our ancestors were still knuckle-walking; the potential lifespan of an intelligent species is something for which we have not a single data point. That is why the Drake equation is at present all but useless – too many imponderable variables.
SF generally ignores this, of course, because having your heroes explore a planet with life at something analogous to a Precambrian stage just is not as much fun. See the TVTropes page Sci Fi Writers Have No Sense of Scale – which is mainly about space but also applies to time.
In The War of the Worlds, Wells stated clearly that the Martians were not prepared for the possibility of infection by Earth’s microorganisms because there is no microbial life on Mars.
Not Wells’ finest moment. How could any biosphere include macroorganisms but no microorganisms?!
Again, the Yacatisma!
Sometimes I think sufficiently advanced aliens exist, and Ancient Astronauts gene-engineered Homo sapiens just to fight for their amusement.
That would explain a lot.
Some SF writers have come up with ideas far sillier.