Is This the Missing Link to Michael's Gesture?

I was perusing io9 one of the foremost sci-fi and pop culture sites on the internet when I came across a nice little article by Robert T. Gonzalez.  In it, Gonzalez covers the release of Charles Darwin's unpublished letters and the impact they will have on modern day scholars and their perception of Darwin.

What struck me immediately was not the content of the article but the leading photo of Darwin with his finger to his lips.

Where have we seen that before?

As Fringe fans know this was the enigmatic gesture proffered by Michael as the series wound down to a dramatic close.  The picture above shows Michael repeating this mysterious gesture to Olivia right after she made quick work of Captain Windmark.

There has many theories as to what this gestures means, some outlandish and some quite legitimate.  But I have yet to see a theory as to where this gesture may have came from or what inspired Michael to use it.

Let me offer you this, Darwin is known to be the world's foremost Naturalist.  A great mind that brought us "The Origin of Species" and "The Descent of Man".  So if we consider what the Observers had told us, that they were the pinnacle of  humanity's development.  The apex of mankind and the legitamate inheritors of the world, what are we to think?

Were they a product of natural selection?  Did they gain their stature atop the food chain through the precepts of survival of the fittest?  The answer would have to be unequivocally no.  If anything, they sidestepped nature and brazenly manipulated it.  There was nothing natural to them at all!

So how does Michael fit in?  Well, he could have meant anything with his gesture but I'd like to think it was a direct homage to Darwin and his thinking.  By putting his finger to his lips, Michael was marking the time that meant the end of the Observers and their perverse take on nature and a return of the natural order once he and Walter crossed into the future and made things right again.

 
Michael's gesture pointed to the time where the "human kind" took its rightful place in history proving Darwin right and making him proud.  And if you listened closely through the sudden silence you could hear the sounds of a child playing gleefully in a park while her parents looked lovingly on.