My pet theory is that music is so universal because it hijacks two systems in the human brain that are necessary for survival.
First, humans are a social species and use language to communicate. Babies learn language by observing and emulating their parents. So it makes sense that humans evolved a rewards pathway that makes it pleasurable to listen to sounds.
Second, the brain is basically a pattern matching and prediction machine. Music is full of patterns, e.g., rhythm and harmonics.
That's why music is so popular -- because it allows the brain to do something which it is very good at and which it also finds pleasurable.
My pet theory (which complements yours) is that it was, before the invention of writing, part of the mnemonic techniques used to perpetuate vital information. Other worthy mentions are story-telling/acting, poetry (rhyme and meter) and painting.
Being innately predisposed to like these disciplines makes one more likely to practice them, become good at them, and help propagate useful info undamaged, thus rising the group's survival abilities.
They were vital for so long (compared to the few millennia since we invented writing) that we still have the taste baked in, even though writing, then the press then computers and photographs took over those roles.
Rhymes and meter are the CRC32 check of prehistory.
I was hoping to add an original thought to this thread, but you nailed 80% of my point. The remaining 20% is that music allows "chunking"[1] complex knowledge into a single song that's easy to remember.
It doesn't handicap them today. I think it would have handicapped them 4000 years ago.
There is actual evidence for my theory BTW. Aboriginal folks in Australia had a tradition of using songs to describe itineraries.
Antique poetry and the bits of oral traditions that survived until today were using heavily structured verses (like the dactylic hexameter). A notable exception is the old testament, whose first parts were transmitted orally before being written down, and which is structured in verses of unknown structure (or unstructured, except for the psalms).
Modern poetry has gradually lost that strong structure. The prevalence of musical anhedonia and amusia may very well have risen in recent times as a result of the loss of utility of music.
Possibly, but it'd be a fairly minor handicap. Remember that people who don't enjoy music have no problem learning music or instruments, and plenty do. There's no obvious way it would result in your death.
We tend to make the mistake of assuming any seeming oddities of the human must somehow be due to evolution. But when we see the same in the rest of the body we often make the opposite assumption and assume it's a vestigial trait, or a coincidence.
My point is that taste in music is vestigial since the invention of writing. Before that it was a selective advantage.
Even if amusia (of which musical anhedonia is a subtype) was prevalent at the time, culture transmission operates at the group level. The mere existance of amusia with such a low prevalence doesn't invalidate my point.
And thank goodness. I have musical anhedonia (https://en.wikipedia.org/wiki/Musical_anhedonia), which basically means that music does nothing for me. I function just fine in today's society, where music is merely entertainment. I probably would've been screwed if I had been born thousands of years ago.
Are people really pleasured by optical illusions, or are they interested by them? I think that most people understand that their brains are struggling to comprehend them, and that is why they are interesting.
Regardless, I don't think there's much evidence (if any) for the idea that the enjoyment of music is the result of a defect in our auditory system.
I would argue that magic eye books and optical illusions are different things. An optical illusion exploits our brains "shortcut" mechanisms, which could be considered taking advantage of a weakness, whilst a magic eye utilises our pattern matching ability, which could be considered as bolstering a strength.
Not sure I've explained myself as well as I could, but hopefully I have.
Every optical illusion is some good aspect of vision failing in a limited case. Evolution is presumably selecting for the good aspect, and not the occasional hallucination it produces.
Even after the invention of writing, music and art is still a vital medium through which to perpetuate vital information. Not all ideas can be distilled easily into words.
My pet theory is that a musical capacity provides a pleasure/reward for the imitation of intentional motor activity. I believe this enjoyment of rhythmic entrainment predated language by roughly a million years and launched cultural transmission of skill knowledge in prehumans.
Humans are (largely) the only animals with cultural transmission of skills. Making stone tools or cutting trees or scraping hides or making fire would have involved much rhythmic motor activity.
First, humans are a social species and use language to communicate. Babies learn language by observing and emulating their parents. So it makes sense that humans evolved a rewards pathway that makes it pleasurable to listen to sounds.
Second, the brain is basically a pattern matching and prediction machine. Music is full of patterns, e.g., rhythm and harmonics.
That's why music is so popular -- because it allows the brain to do something which it is very good at and which it also finds pleasurable.