Superb Fairy-wren embryos distinguish between adult wren calls before hatching.

On the previous page, we saw that, in 2012, a study found that the Superb Fairy-wren teaches a password to its young before hatching. If a hatchling knows the password, it is fed. If the nest holds a cuckoo bird hatchling, who does not know the password, the nest will be abandoned, or the cuckoo bird will not be fed if other hatchlings remain in the nest.

That 2012 study anticipated a follow-up study which would identify the mechanism of the embryonic learning in more detail.

Listening response of bird embryos was evaluated with noninvasive heart rate monitors.

While an observational study, such as the 2012 Superb Fairy-wren behavioral study, yields useful results, the results of a physical reaction study, such as a heart rate monitor study, yields information which is well-controlled. Such a controlled study may tend to validate and expand upon the observational study.

The 2012 research paper had stated:

Model systems that use noninvasive approaches (such as MRI) to study embryonic neural and cognitive development are likely to stimulate new fields of inquiry over the coming decades.

In October, 2014, results of a new study were published. The second study was based on a different study method, of hooking up eggs to a non-invasive heart monitor. One goal of the study was to identify the exact mechanism by which the embryonic learning was accomplished.

We’re not the only species that can recognize voices in the womb: Inside the egg, tiny songbirds called superb fairy wrens can discriminate sounds from different birds of their own species, a new study reveals.

The embryos pay attention to surrounding noises and can tell if they are listening to calls from a fairy wren they haven’t heard before, according to the study published October 28 [2014] in the journal Proceedings of the Royal Society B. [Biological Sciences]. The findings represent the first time a species other than humans has been shown to distinguish between individuals in utero.

This remarkable ability allows growing embryos to learn a “password” from their mother, which they then use to beg for food upon hatching.

“We have tended to use birth or hatching as the starting point for the development of behavior,” said Robert Lickliter, a developmental psychologist at Florida International University in Miami, who was not involved in the study. (See [the source article for] pictures of extreme animal embryos.)

“This work shows that it’s worth going back further in development to see where the roots of behavior come from.”

Bird Brains Tune In Early

For the experiment, scientists plucked 60 fairy wren eggs out of wild nests in southern Australia.

The team then hooked the eggs up to a noninvasive heart rate monitor. [Here, the article refers to a video, “Do Parrots Name Their Babies?” which may demonstrate the heart monitor research technique.]

Why a heart rate monitor, you might wonder? Because research on humans has shown that fetuses are most attuned to their surroundings when their heart rates are low.

They aren’t “moving as much, trying to stay quiet, trying to be attentive,” said study leader Diane Colombelli-Négrel, a postdoctoral researcher at Flinders University in Adelaide, Australia.

You can read the rest of this article and listen to a superb fairy wren’s call at this website.

Also see the 2014 source research paper and study method here.

Click next page to read a study about how a similar ability allows a human baby to learn features of its future sound environment while still in the womb.