The [eyeshine][1] of certain vertebrates was an evolutionary side-effect, when these animals evolved in an environment where artificial lighting was not available at night. Therefore eyeshine cannot be compared to the glowing eyes of robots. (This side-effect must have saved countless humans who were fortunate enough to gather around a fire).

However, there's a perfectly valid reason to have glowing eyes for humanoid robots, or robots who interact vocally with humans and have a face. Humans would be far more comfortable talking to a "face" with eyes rather than [a globe of light][2].

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Which means, glowing eyes are better than no eyes at all. But if you have the luxury to have eyes with features, it would be way better than two glowing circles. [This paper][3] ([ACM link][4]) discusses in length about the perception of humans on humanoid robots with varying features. This is what they had to say about the importance of eyes (emphasis mine):

> Human eyes are complex and intricate objects. *To project humanness a robot
must have eyes, and the eyes should include some complexity in surface detail, shape of the eye, eyeball, iris, and pupil*.

They also have identified that *eyebrows* do a large part in making a robot humane.

  [1]: https://en.wikipedia.org/wiki/Tapetum_lucidum#Eyeshine
  [2]: https://www.youtube.com/watch?v=UgkyrW2NiwM
  [3]: http://www.cs.cmu.edu/afs/cs/Web/People/kiesler/publications/2002pdfs/2002DiSalvo.robots%20unequal.pdf
  [4]: http://dl.acm.org/citation.cfm?id=778756