the "heart" answers are generated in the brain as much as any of the other ones.

There are plenty of neurons outside the brain, so I don't know whether that's true. Regardles, the motor cortex has somewhere a representation of the hard that"s "in the brain". Given that panthom limbs can hurt it's probably somewhere in the motor cortex with feedback channels to the actually body location.

Why should they have any such perception?

That's a complicated question.

I would preface it by saying that language is evolutionary a recent invention. We are not evolved for that purpose. It's a byproduct. An accident more than a planned thing. A dog doesn't need to have a verbalized understanding of a situation to decide whether to do A or B.

It devels into the nature of what emotions are. In academia you have plenty of people who are in a practical sense blind when it comes to perceiving what happens in their body. People who declared blindness as virtue.

If a man get's an erection and his attention goes to that part of his body, it's evolutionary useful for the men to do things lead to having sex.

If the same man has an empty stomach and the attention goes to perceiving the feeling of an empty stomach, that in turn leads to different actions.

Somewhere along those lines it made "sense" for evolution to develop a system of emotions where emotions are "located" somewhere in the body. Reuse of already existing neural patterns might also play a huge role. Evolution frequently works by reusing parts that already exist and were build for other purposes.

Years ago in an effort to understand the brain I brought a book called Introducing the Mind and Brain by Angus Gallatly who's a professsor of Cogntive Psychology.

At the beginning when he recaps the history of the mind he writes:

Homer's vocabulary does not include mental terms such as "think", "decide", "believe", "doubt" or "desire". The characters in the stories do not decide to do anything. They have no free will.

Where we would refer to thinking or pondering, Homer"s people refer to speaking to or hearing from their own organs: "I told my heart", or "my heart told me". Feelings and emotions are also described in this half-strange, half-familiar manner. Feelings are always located in some part of the body, often the midriff. A sharp intake of breath, the palpitating of the heart, or the uttering of cries is a feeling. A feeling is not some inner thing separate from its bodily manifestation.

At the time I first read those words, I also agreed with the strangeness of the idea. Now years later I'm touch with my body well enough to completely understand why it makes sense to speak that way. I'm not anymore blind. Even on a bad day I can tell apart midriff/stomach, heart and head. I also know people with better kinesthetic perception than myself.

When it comes to return hard questions, why do you think that human have beliefs? The concept doesn't seem straightforward enough that it was around in Homers days. Do you think dogs have them? Doves? Ants? Caenorhabditis elegans?

Bonus question, when do you think that humans started "believing" in beliefs?