Friday, September 2, 2016
Birds sing to their unborn chicks to warn them about hot weather
This is incredible. Yet another reason not to eat birds!
When the weather is hot, zebra finches sing a special song to their eggs that preps them for the warmer climate.
The song appears to affect the unborn chicks’ development, helping them to cope with heat and produce more chicks themselves – a strategy that may help the birds deal with global warming.
Some species of birds call to their unborn offspring, says Mylene Mariette at Deakin University in Victoria, Australia. Birds that hatch at an early stage, such as zebra finches, were not thought to do this.
But they do – and they seem to take this to a whole new level. When Mariette and her colleague Katherine Buchanan put microphones in 125 zebra finch nests in an outdoor aviary, they noticed the parents sometimes sang a specific song when they were alone with the eggs. They only did this in warm weather when their chicks were close to hatching. “It really looked like they do it to communicate with the egg,” Mariette says.
“The chicks that heard the song and grew up in hot nests, went on to produce more chicks themselves“
To see if they were listening, the team incubated eggs in the lab, playing the song to half of them before returning the hatchlings to nests scattered around the aviary.
Of the chicks that had been played the song, those raised in nests in hotter parts of the aviary weighed less than those in cooler nests and those also in warmer nests but that hadn’t heard the song. Smaller birds may shed body heat more easily or perhaps growing is more stressful during hot weather, Mariette says.
Female finches that had heard the song also produced more fledglings in their first breeding season (Science, doi.org/bpkx). This could potentially help them deal with global warming, says Mariette.