This is one that doesn't come up as part of life in Japan, and probably looks pretty strange to a child growing up outside the English-speaking world. But for some reason, proponents of creationism and the theory of evolution refuse to let the subject rest.
The theory of evolution states this:
- Within every generation of a given species, there are minor mutations (many of them).
- In any individual or subpopulation, the sum of the mutations may confer an advantage in life, such as avoiding predation, finding food, finding an optimal mate, etc.
- As the above process repeats, traits that strengthen the ability of a species to flourish in its environment will be favoured within the population as a whole. That is, those individuals and subpopulations with strong traits will flourish and pass those good traits onto their offspring who are both well-provided-for and carry the strong traits themselves.
- In this way, the evolution of a species over time is accomplished, and the creation of new species occurs when different populations within one species evolve to suit different local environments.
Creationism follows from Christian mythology, and states that the omnipotentent diety that created the Universe created all current extant species just as they are. I'm not sure how creationism accounts for extinct species, the close ties that exist between many species, or the way that unrelated species fill the same niche over different parts of the world and at different times. Mythology being what it is, perhaps accounting for things is beside the point.
The point truly is: this is a moot debate given the timelines involved. We're not able to speak with the omnipotent diety to clarify the theological stuff, and we're not able to demonstrate the theory of evolution "in action" to a sufficient degree to dissuade the nay-sayers of that theory. It's a draw, and it likely always will be.
And as such, it's not an area to getting upset about. In fact, in the pursuit of a happy existence, one should probably avoid all such "debate" as simple argument for its own sake. Enough, I say!