Horses show emotion while observing social interactions between other horses and humans in videos.

Research Reference:

Trösch, M., Pellon, S., Cuzol, F. et al. (2020). Horses feel emotions when they watch positive and negative horse–human interactions in a video and transpose what they saw to real life. Anim Cogn 23, pp. 643–653

Link:

https://link.springer.com/article/10.1007/s10071-020-01369-0?fbclid=IwAR278hOdLV51HytST89t4NF1C2mFiSQWWw75hq3H_IoLNnkWIiinCj1cqsM#citeas