Thread by @cedricboeckx

Does #domestication (reduced reactive aggression) potentiate vocal learning? If so, how exactly does this happen?
@Thomas_ORourke @ptsgmartins @asano_rie @ro_tachi @okanoyalab & I look into this question in this new @TrendsCognSci paper 🧵
authors.elsevier.com/a/1cpx74sIRvHk…

Kaz Okanoya has done extensive work documenting differences between the songs of the domesticated Bengalese finch and the songs of its wild relative, the white-dumped munia.
Various measures point to increased variability and 'complexity' in the song of the Bengalese finch.

We built on work @Thomas_ORourke and I did showing that the glutamate neurotransmitter system is disproportionately targeted in the evolution of domesticates: sciencedirect.com/science/articl…

And we zoomed in on the role of glutamate in the regulation of stress responses and aggressive behaviors that are attenuated under domestication; we focused on the way glutamate controls dopamine activity in neural circuits crucial for vocal learning (key: striatum)

Attenuated glutamatergic signaling impacts the dorsal and ventral striatum differently (reducing dopaminergic signaling in the former, but boosting it in the latter), and we show how this could lead to increased innovation and variability in vocal production abilities.

What I like most about the account is the generic nature of these effects (nothing really specific to vocal learning), and also the implications it has to understand certain disorders like Tourette syndrome.

There is no single ‘magic’ bullet in evolution, and this proposal is to be understood in a broader context (see Box 4 of our paper). E.g, this work complements work I did with @Constantinatheo & @erichjarvis on oxytocin and its role in vocal learning: royalsocietypublishing.org/doi/10.1098/rs…

The paper adds a neural circuit perspective to the very insightful discussion by J. Thomas & @SimonKirby about how (self)domestication could have impacted the evolution of our language capacity, with important roles for reward & motivation (thx Simon!)
link.springer.com/article/10.100…

Our proposal also opens up new avenues of research (for me, at least), mentioned in the conclusion: e.g. how social learning & social organisation shape grammar, touching on important themes @Limor_Raviv has shed new light on in her PhD thesis: repository.ubn.ru.nl/handle/2066/21…

In closing I want to thank the three thoughtful reviewers, and TiCS editor @LindseyDrayton for the care with which she went over our text, making sure it is written in a way hopefully many readers will find accessible. Thanks above all to all my co-authors.