Activation energy is the amount of energy required to initiate a chemical reaction. The activation energy can be determined from reaction rate constants at different temperatures by the equation. ln(k 2 /k 1) = E a /R x (1/T 1 - 1/T 2).
Robins also eat other small insects, berries, fallen fruits, and especially Rosaceae fruit in the fall and winter. Robins cannot digest hard fruits or grains, so they stick to soft fruits and organisms with softer skeletons (Howell, 1942). http://www.bio.davidson.edu/people/vecas...
For the most part sparrows are seed eaters. The seeds that the sparrow will normally prefer are millet, grass, thistle, weed, and sunflower seed. Even though the sparrow is primarily a seed eater they will eat small insects, and are often seen in parking lots and parks where scraps of food are left about.