As you pointed out, blinking is likely a multi-functional adaptation for humans. An interesting study on the protective nature of blinking found that pregnant women actually blink several times more per minute than non-pregnant women. On the other hand, a different study found that when several individuals watch the same tv show, they often blink in synchronicity and another study found that people tend to blink more when they are engaged in conversation. What those studies suggests is that blinking likely acts as a way to refresh an individuals attention. Great post. Very interesting.