Momma keeps the eggs warm from her own body temperature. A robins's body temperature is 104F. Feathers insulate her body and keep the heat in, so to keep the eggs warm, the feathers on her belly fall out creating a "brood patch" of bare skin.
Picture credit Bill Hinton, Jr. http://www.learner.org/jnorth/tm/BroodPatch.html
You would notice if you watched Ms. Robin return to the nest that she might turn the eggs with her beak and then when she sits she wiggles around a bit to get the brood patch exposed and making contact with the eggs in just the right way.
Receptors in the brood patch allow the bird to monitor the egg temperature and she will adjust her incubation accordingly. Pretty neat, huh?
Columbine is Science. If you have followed my other blog in the past years you know that Columbine is one of my favorite flowers. The wild variety, Aquilegia canadensis, is common in our yard, and possibly in the woods nearby, but more likely north of here and into Canada.
The European Columbine, A. vulgaris, is nice also, and is common in our yard. I suspect the former owner of the house, who was very cosmopolitan, they say, introduced these. They come in several colors and the pink ones are what we have.
They are tall and just dance in the wind. They might be doing the jitterbug this afternoon, from the looks of the weather report.