Being an observer of "Raising a House Finch Family" on camera has been quite the experience.  Obviously, the whole Cowbird nightmare was a piece of it.  What has been equally-educational to me is how different a Finch family is from the other songbirds who have nested on camera.

Finch Nesting Differences

• Fresh, green plant material is used in nest construction.  The other nests I have observed contain only non-green material.
• The nest cup is shallower and much more-loosely "thrown" together.  (The bottom to the current nest on my property is completely pushed away.  The nestlings are resting on the bare wood of the platform.  Makes me wonder what would happen if this nest were on a branch!)
• The female parent spends considerably more time sitting on the nest -- almost constantly during incubation and well-into the first week of the nestlings' lives.
• It appears the female parent's primary nourishment comes from her mate feeding her -- compared to the male providing an occasional meal to the female.
• The male parent also appears to take primary responsibility for feeding the nestlings -- a duty shared by my other on-camera songbird parents.
• Nestlings are fed almost exclusively a vegetarian diet -- quite the contrast to the mealworm-feasting families inhabiting my other nest sites.
• The parent eats the plant/seed material and then regurgitates it when feeding the nestlings -- hmmm -- some similarity to cows here.  I wonder if that's what attracts the Cowbirds?!  (Okay, I don't really wonder that.)  Regurgitation behavior has not been observed among the other nesting species.
• The shape of the nestlings' beaks is also quite different -- much narrower; almost heart-shaped -- not broad and triangular like the others.