Essentially we get the general idea of what other unknown ecosystems might be.
Yes that's exactly what I was saying.
But then again it could be so odd it could spontaneously combust our minds.
Don't think I would go that far. Though when it comes to space exploration true often ends up being stranger than fiction.
Anyway back on topic Aliens could be similar to animals here. We have no idea how other creatures on other planets could have developed.
Yes and no. We do have a grasp on the chemicals that make up life here and we can observe how these chemicals behave under certain conditions. We can also observe how other chemicals behave. As result we can make predictions based on this of what the basic starting point for life might be like on another planet and what those basic starting condition might be like as well. From there we can start predicting the different scenarios of how that life and the planet could evolve over time.
For instance we find a planet around a G-type star (like our own) an it's about the same distance from it's star as ours. From this we can determine that it's possible to have liquid water on this planet and that carbon based life would be the likely form of life on this planet. We can also figure how life might be depending on the size of the planet. This would have an impact on the weather and the gravity, both of which would affect the evolution of life there. There are of course many unknown factors. For instance this planet has n abundance of oxygen due to the development of planets. Perhaps life on this Earth like planet uses different gases. Or maybe they developed added features to better withstand living in an environment with much higher oxygen than our own.
But look at us. We don't have predatory instincts. (Of course there are cannibals...) Then Again we may just have a more advanced form of predatory behavior. We kill cows and pigs to eat them, Of course we eat fruits and vegetables as well but still.
Ever go hunting? We evolved from a species of hunter gathers. Just because we are omnivorous doesn't mean we weren't a form of predator. Early on the development of our brains was likely largely impart to to us developing the ability to eat meat.
Just for a few examples many species of bear are also omnivorous, piranha are omnivorous, coyotes and dingoes are omnivorous as well though they do prefer meat. Would you say those species are not predators?
