eyes appear bigger, hence more infant-like
The appealing visuals of the eyebrow movement in dogs now look like something that we humans have come to understand as a human attribute. Kaminski, Juliane, et al. “Evolution of Facial Muscle Anatomy in Dogs.” Proceedings of the National Academy of Sciences, vol. 116, no. 29, 17 June 2019, pp. 14677–14681, www.pnas.org/content/116/29/14677, 10.1073/pnas.1820653116.
The heightened eyebrow movements may have been perceived by humans as markers similar to those established during human−human communicative interactions.
What is it the raised eyebrow indicating to humans then?
Wolves, in comparison with other canids, are described as having an intense gaze-signaling face (27).
The Wolves seem like they have an intense gaze because of there predatory nature. I think before we domesticated wolves, there were probably a lot of wolves that had attacked human settlements for food 33,000 years ago.