According to the concept of “survival of the fittest," if a population of birds eats worms that they find deep under ground by using their beaks, which members of the bird population would be more fit?

The birds that have beaks better equipped for the task of eating worms under ground. Narrow, sharp and strong beaks would be better at digging through the dirt to find worms. So birds with these types of beaks would be fitter and thus, would survive.

The proton has a positive charge while the neutron has no charge they both make up the nucleus of the atom while the elections have a negative charge and surround the nucleus of the atom. the protons and electrons are used to calculate the atom's mass whereas the neutrons don't affect the mass