Being the only child is a unique position in a family. Without any siblings to compete with, the only child monopolizes his parents' attention and resources, not just for a short period of time like a firstborn, but forever.
Like gravity and plate tectonics, evolution is a scientific theory. In science, a theory is the most logical explanation for how a natural phenomenon works. It is well tested and supported by abundant evidence. It means quite the opposite from our informal use of the word theory, which implies an untested opinion or guess. As a scientific theory, evolution enables scientists to make predictions and drives investigations that lead to new kinds of observable evidence.
Scientific Theory Meaning. Now I just used the word theory. Theory in the scientific use of the word is different than the everyday language usage today. Most people today use theory as just a hunch, guess, belief, or proposal. Science uses the original meaning of theory: a logical, systematic set of principles or explanation that has been verifiedâhas stood up against attempts to prove it false.