By Jonathan Webb Science reporter, BBC News
19 August 2016
When the weather is hot, zebra finches in Australia sing to their eggs - and these "incubation calls" change the chicks' development, a study has found.
The surprising discovery suggests that the birds are preparing their offspring for warm conditions after they hatch.
Scientists collected eggs and incubated them in controlled conditions, playing recordings of the incubation song.
Compared to a control group, hatchlings that received these calls grew more slowly and coped better in the heat.
Writing in the journal Science, the researchers say this is the sort of adaptation that could help animals acclimatise to rising global temperatures.
"It doesn't mean that they will still be able to breed at extreme temperatures - this was within the range they currently experience," said the paper's lead author Mylene Mariette, from Deakin University in Geelong.
"But what's encouraging is that it's a strategy that the birds use to adjust the growth of their offspring to temperature, that we didn't know about."
It is also the first time that singing to unborn chicks has been shown to yield such long-term results.