Thanks for sharing this. It is an interesting read though in many ways not massively surprising if you spend time with your chickens.Another article I link to when an opportunity arises. There are quite a few others now. People will read this article and forget the information it contains because people don't want their chickens/pets/livestock/food to have any of the qualities such studies suggest chickens have.
https://link.springer.com/article/10.1007/s10071-016-1064-4
I do remember though that the thing that surprised me most when I first encountered chickens was that they have personality. Which of course is now obvious but still a joy.