Well, they've been proved to help if you're a songbird, anyway.
The nub of the matter is, what do birds like in a song?
For a long time the answer was thought to be a matter of variety. I suppose this was analogous with humans, where a man who can talk about music, current affairs and fashion is generally regarded as more fascinating than one who talks about steam trains the whole time.
As it turns out, though, this is not the case with song birds. Female birds prefer one song sung really very well indeed to lots of songs sung indifferently.
Which, if you think about it, is also analogous with humans.
So, what counts as singing well?
It may be a matter of the speed of the trills, or the complexity of the song, or the singing in the local accent (yes, songbirds do have accents), or just the sheer loudness.
Or, if you're a canary, sexy syllables.
A sexy syllable is one where a bird uses its syrinx (that's the avian equivalent to our larynx) to sing two notes at once.
This isn't easy for a human, but something similar can be achieved (and often is) with the help of other singers (I note that groups of singers have been known to prove attractive to young females).
photo of One Direction by Brett Robson – Global Photographics
If this is hard to arrange then a guitar might help. Or even a recording of some kind.
In fact, the idea of sexy syllables might explain rather a lot, mightn't it?
Word To Use Today: syllable. This word comes from the Greek sullabē, from sullambanein, to collect together.