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Message: <blockquote data-quote="elkcub" data-source="post: 3425546" data-attributes="member: 14473">I'm a bit sorry that I attached that article, since examining it in detail raises several questions.  I tend to conclude that anatomical and optical factors got mushed together in a confusing way.  Frankly, I've got questions/clarifications about every point.  For example, in #1 what does "sideways eyes" mean in the context of a 'wider field of vision?'  I think they're talking about eye placement on the head not pupil shape.  Similarly, although not stated, the 50 deg. eye rotation in #5 is, no doubt, vertical rotation, which would indeed significantly exceed human capability. Why is that facilitated by rectangular pupils; wouldn't semi-circular pupils be better?   The authors refer to "depth perception" (which should not be in interpreted as depth of focus).  Again, in this context it's primarily determined by eye position on the head, which has little to do with pupil shape, per se.  Moreover, wider eye placement on the head reduces retinal overlap and minimizes a visual horopter.  Hence, there should he less stereopsis rather than more, and diminished depth perception.  Alzo, ... #8 has me stumped.  Within the limits of my curiosity I'll try to locate the original publication and see if it makes any more sense.  But, for now, I apologize for posted this with so little vetting.    :-C Ed</blockquote>