Mommy and Daddy fairy-wrens sing "food passwords" to teach their eggs to sing

"Superb fairy-wren (Malurus cyaneus) mothers sing to their unhatched eggs to teach the embryo inside a 'password' — a single unique note — which the nestlings must later incorporate into their begging calls if they want to get fed." Zoë Corbyn in Scientific American, on a very unusual example of avian communication.



  1. Very clever, wrens, very clever. 

    Tomorrow we learn that avian brood parasites of the wren have mastered MiTM and password replay attacks.

    The day after that, it turns out that wrens are capable of cryptographic challenge/response authentication…

  2. I assume these birds must have quite a brutal history of brood parasitism by some other species. One wonders whether the culprit species is still around, or whether the fairy wrens’ fantastic evolutionary gambit wrote their epitaph.

    1. “The trick allows fairy-wren parents to distinguish between their own offspring and those of the two cuckoo species that frequently invade their nests.”

      1. Makes sense. I’m guessing that the cuckoos must have other options as well, otherwise it seems like this would really make things difficult for them.

    2. Why parisitism per se? No point in feeding a half-deaf chick. Especially if the current research about birds navigating by ulta-low frequency environmental sound is accurate.

      1. The initial cost of implementing this defense must have been substantial, that’s why. Chicks that didn’t have the ability to pass the challenge-response test wouldn’t necessarily have been defective in other ways. A lot must have starved that would otherwise have made it to adulthood.

  3. Even cooler- while this isn’t the first evidence of an unhatched chick being able to hear while it’s still in the shell, it may be the first evidence of any animal having memories from when it was an embryo.

    It reminds me of the dragons in Naomi Novik’s Temeraire series, which hatch able to speak the languages they heard from inside the egg. It would be pretty great if something a fantasy writer made up turned out to actually exist…

  4. I’ve always found the insult “bird-brain” to be incredibly presumptuous. This illustrates that point nicely.

  5. Didn’t I once read that human babies were born preferring the ‘accent’ of their parents?   If that is true is would imply some kind of in utero learning.

Comments are closed.