22 August 2016
How are birds coping with heat?
Many birds talk to their eggs and there’s evidence that the eggs hear and respond. For instance, superb fairywrens sing to their eggs and before they hatch the babies sing back!
Now scientists at Deakin University in Australia have discovered that in zebra finches what the eggs hear and how they respond is even more amazing than we knew.
In the last days of incubation, zebra finches (Taeniopygia guttata) sing a special song to their eggs but only when it’s hot outside — greater than 26 degrees C (78.8 degrees F).
The eggs hear the song and it changes their lives.
After they hatch, babies who heard the “hot call” grow more slowly than those who did not. Not only are the “hot call” babies smaller as adults but they’re more successful breeders in a hot climate. Surprisingly, this effect extends into later generations.
Small bodies cope better with heat than large ones, so signalling for a smaller size is a great adaptation for a warming climate.
But how does the zebra finch song bring about this result?
Read more in Science Magazine: Zebra finch call prepares their eggs for climate change.
Wow, very interesting! Usually the goal is to fledge larger chicks because they in turn produce more offspring, but this example shows the opposite! I can’t wait to see if they can replicate this in the wild!