In Ovum Learning by Superb Fairywrens

Male breeding plumage. Superb Fairywrens are usually gray brown. 

As reported in Discover, an article in Current Biology (behind a paywall) involves a study suggesting that Superb Fairywren chicks learn their familial feeding call while they are still in their eggs. Each family has a unique call passed from mother to chicks, and, given its uniqueness for each mother and chicks, appears to be learned. The mother sings it to her eggs, and the chicks emerge apparently knowing the song. The clear implication is that the chicks can learn before they hatch.

The article speculates that the learned song allows the mother to distinguish her chicks from impostor cuckoo chicks that are lain in her nest. Apparently it's not too effective, and only works about 40% of the time.  Cuckoo chicks, by the way, usually hatch before other chicks and grow faster, and when the other chicks emerge they kick them out of the nest. That behavior is not learned -- there's no cuckoo mother to teach it -- and so must be innate.


Why This is Interesting (Other than, you know, Being Interesting)

There are three broad and interrelated processes that control development (not two, as the old saw  "nature versus nuture" suggests). They are (1) genetics, which determines how structures form, (2) epigenetics, which turns some genes on or off due to physical cues, and (3) learning and growth (or, sometimes, "pruning") in response to environmental material and sensations. It is clear that all of these except maybe learning can take place in the womb. This study lends support to the fact that learning can take place in the womb, at least later in development. So, to me, that's interesting. Well, enough about that.