When more than two are in a photograph there's a much more complex dynamic. The field is generally centered on the group, but often the surrounding scene is an essential part of the composition: the group is located in a context, and the context may in fact be the reason the picture was taken.

This one has many thousands of relatives, depicting R&R of victorious armies:
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On the back it says 'Venice, May 1945'

And this one also represents a genre in family photography: The Four Generation Photograph:
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Team photographs are pretty common. I was told that the gentleman in the bowler was Middleton's undertaker:
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Three sisters. Don't you dare...
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Mens Bible Class, M.E. Church
Westbrook Me. Feb 18 1917:
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A few of the denizens:

Is this evidence for Bluenose polyandry?
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The conductor's hat says "W&A Ry", which I decode as Western and Atlantic, based in Atlanta GA:
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How did this one find its way to Nova Scotia?

The symmetry of this one is pretty remarkable, but it's the hands that stand out:
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Annie Salter, Sadie O'Dell Young, Will Salter:
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Something distinctly Diane Arbus-like here:
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Even at the best of times, class reunions are fraught with discomfort. This one is Class of 1901, taken in 1911:
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...and this poor man is caught right in the middle, a deer in the headlights:
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This one is probably grandparents:
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I can't overcome the conviction that at least one of these is in drag:
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on the back: you know these without me telling the names
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