Sheep like smiles say researchers

Researchers at Cambridge University have discovered sheep prefer smiling or relaxed human faces, over angry or stressed ones. — Sheep like smiles say researchers (BBC)

What about sheepish grins? Okay, that was a ba-a-ad joke.

The news story says this research took place three years ago. What is the “news hook”? Is this article discussing recent research? If so, where was this recent research published? A web link or journal name would be immensely helpful. National Geographic reported on Kendrick’s sheep memory research in 2001.

(Thanks for the suggestion, Rosemary.)