Left eye? Right eye? American robins have preference when looking at decoy eggs

Just as humans are usually left- or right-handed, other species sometimes prefer one appendage, or eye, over the other. A new study reveals that American robins that preferentially use one eye significantly more than the other when looking at their own clutch of eggs are also more likely to detect, and reject, a foreign egg placed in their nest by another bird species—or by a devious scientist.

source https://www.lifetechnology.com/blogs/life-technology-news-blog/left-eye-right-eye-american-robins-have-preference-when-looking-at-decoy-eggs