I lean towards F & B myself. However having had some para-normal experiences I don't discount it either.
Having spent most of my youth in bushland in Africa and Australia, I know the feeling of being watched. Watched by what? Everything that you pass by... Birds, snakes, lizards, insects.
I remember a feeling of dread once when I was roaming the bush behind my house in Zambia. I had that feeling of bieng watched... I turned around and there was a chameleon quite close to my head. If there was a feeling of dread I wondered if it was on it's part - 'Bloody hell... would you look at that thing. I better be still... change colour' LoL
I believe that where ever you go, you are being observed. Just as you take in your environment you are equally a part of someone else's environment or something's environment.
It takes two to have an encounter, whether both parties are aware of it or not.
In reference to the aura idea... It make sense. Whatever dread or feal we feel might be the very reason why the bush falls quiet. If we feel it I'm sure other creatures can experience it also.
As for IR sensitivity, there are many animals that have IR capability.
Here's a link you can check out it's about the eye and IR capabilties in certain animals. To us we would experience this capability as para-normal but it's everyday ho hum for the pit viper.
Another note about IR vision. Deep in the oceam there is a species of copepod (microscopic organism) that scans the dark with IR. Most of it's hapless prey have no idea as they haven't developed vision because of their virtually nil light environment.
The curious thing is, one organism has evolved to detect when it's being scanned in the dark and takes subsequent action. These are tiny creatures with very sophisticated vision systems. Astounding.
There are also many types of fish, shark and ray that have electric fields that they use to appreciate their environment. The platypus can detect currents as weak as a millionth of a volt when searching for food. If this is not an 'aura' of some description I don't know what is.
My point is that there are billions of living things that interact with the world in many and varied ways. Nothing should be surprising, only enlightening.
This was a great poll to read.