The show's composer focused on the idea that melody, rhythm and harmony would attract babies' newly developed sense of hearing
Scottish Opera said it has had an "amazing" response to a new show aimed at its youngest ever audience.
Baby O - which is for babies as young as six months old - includes arias about bees, ducks and wellington boots.
The show, which will tour Scotland, is the brainchild of Scottish Opera's education director Jane Davidson.
She compared the melodies featured in the event to the musical patterns of nursery rhymes and said the babies were "completely fascinated by it".
Ms Davidson told BBC Radio Scotland her idea of staging work for six to 18-month-old babies was initially dismissed as madness, and that she was "slightly worried" about their response.
"I thought they'd just lie there screaming," she said.
"But you've never seen such gigantic sets of eyes, they're just completely fascinated by it.
"The show does start off quite softly and it seems to be that once they get used to it you can really zoom up into fifth gear."
She said the show's composer focused on the idea that melody, rhythm and harmony would attract their newly developed sense of hearing and looked at how nursery rhymes have repeated ascending and descending patterns.
"That's actually one of the links with opera, because there are a lot of musical patterns that are repeated," she said.
As well as entertaining and boosting the babies' IQ, Ms Davidson also hopes the 30-minute production will inspire a whole new audience for full-scale opera in the future.
She said: "The younger we turn children on to really interesting, exciting, high-quality art, the more they'll be aware of what the possibilities are.
"We are looking to develop discerning audiences of the future, even if it's 25 years down the line."