1. The animals are there because central park has a massive zoo in it, I assume that they all escaped from there after becoming so hungry because their 'zoo-keepers' would've abandoned the city, died or became somewhat rabied.
2. He isn't insane, but because humans are sociable beings, we find it difficult to function correctly if we're alone for such a long amount of time (hence the reason why solitary confinement is incredibly unethical), so we will try and compensate for the fact that we're alone. Just like someone would talk to a teddy, and if it fell to the floor, go 'what did you do that for?' jokingly. But if you woke up one day and it was somewhere completely random where it couldn't possibly be, you'd probably question the fact, is it real? Because you can tell by the way he shoots him there is some desperation for him to spend time with people.
3. The 'creatures' are just people who are carrying the virus without death, acting as if they're rabied, they need food and are desperate for it, acting in inhumane ways to do it, the virus (I assume) kills off brain cells or something, so they will not be able to function and act like we to. But I'm sure it'll put them in a primitive state enough to set a trap, especially if they copy another persons behaviour.
By the way, when they were talking about basic human instincts, he was meaning survival skills, for example their natural instinct to not go out in the sun.
4. Because the shade under the bridge is shade during the day, whereas at that point in the film, it is sunset, so it isn't getting shady, it's actually going dark. (The monster person there is the 'leader' throughout the film btw).
I thought the film was absolutely amazing, the creators have made anyone who watches it feel so solitary, there isn't even a soundtrack to it, only some diegetic content (Bob Marley). It only had anything in it that was completely necessary, the reason he didn't want to get into the safe is because he missed his family and saw the butterfly and remembered it, especially after the woman was telling him 'God told me to come here', his mission was over. It was his ground zero, and he'd finished his job that he was hanging around to do, he actually had nothing left.
Everyone that he loved was gone, so what's the point in hanging on?
I hope there isn't too much conjecture in there, I was just trying to explain as best as I could what I thought the best answers to your question were, and I may have only read a couple of other peoples answers before answering myself, so sorry if i've repeated myself.
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Great film. I dont see why Will Smith stayed inside that glass room at the end. Why didnt he go through that tunnel with the others with the blood. Then he could of got all the credit for saving the world.
Who cares about credit when all of your loved ones have been lost to the virus?
I could tell my parents didn't really like the film when I left it, but I thought it was actually amazing.
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Originally posted by Volv
And what was stopping these animals from dying of starvation meanwhile?
The deer type things were probably eating shrubs and stuff which would've covered the entire city and central park (which we can see), and they grow, survive have babies etc, then the lions just eat those.
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