Seducing a female canary isn’t easy. They are picky, frankly, looking for males particularly adept at singing “sexy syllables” that may indicate their overall genetic robustness. Researchers have previously determined that unlike most vocal notes produced by a male canary, the sexy trills require “extraordinarily fast and coordinated alternation between the left and right sides of the syrinx (the avian vocal organ) more than 16 times a second.
For the male canary capable of executing this performance — even on tape — caged female canaries assume postures inviting copulation.
Now researchers at John Hopkins University have bathed the entire brain of male canaries with testosterone to see if male canaries sing better songs capable of seducing females. It’s known that the medial preoptic nucleus part of a canary brain — or POM — controls sexual motivation. POM operates in humans as well.
In this recent study, researchers created three groups of male canaries: 1) POM only testosterone application; 2) entire brain testosterone application; and 3) no testosterone given. The results confirmed that while male canaries receiving the POM only applications of testosterone sang more frequently than the control, they couldn’t hit the seductive trills required to inspire the female canary to copulate. Only males receiving the entire brain bath of testosterone could pull off the five-star performance.
“The quality of the song that is required to successfully attract a mate and then the process of attending to the female, or singing to her, when she is there … requires the coordination of multiple brain regions,” says graduate student Beau Alward, the lead investigator.
Promising insights may also come for seduction among humans, given the reality that like humans, the canary brain is able to change its neural pathways and synapses in response to changes in behavior, the seasonal environment, and injury. “The hormones in these birds are identical to those in humans and they can regulate brain changes in a similar manner,” said Gregory F. Ball, vice dean for science and research infrastructure and professor in the Department of Psychological and Brain Sciences in the Zanvyl Krieger School of Arts and Sciences. via