Is it appropriate to assume that..........?

Interesting question. I've learned that the moment I assume something I'm in error. There are scientists who make a good case for intelligent design but deny believing in a personal God. Watch the video "Mystery of Life" and you'll see that those scientists shy away from any talk of God but recognize that the complexity of life at its smallest level is too intricate, too perfect, to be happenstance.

Although it isn't always a good idea to assume anything about anybody 100% of the atheists I've met outside of Y/A believe in evolution.

No, it is not. Although I suspect that the vast majority of them are, since atheists in general operate on evidence and there is plenty of evidence for evolution. Recognize that a very large percentage of "christians" are also evolutionists. It is primarily the hardcore "literalist" sects of christianity that are primarily creationist.

Not necessarily. Zen Buddhists are (technically) atheists, having no belief in an anthropomorphic "higher power". They do not all accept the theory of evolution via natural selection as correct.

In general, just ask someone before you assume a specific aspect of their beliefs unless the religion or philosophy they claim to adhere to specifically refers to your question already.

Its never appropriate to assume anything about an entire group of people.Its usually not even a good idea to make assumptions about an individual.

It is not a good idea to assume anything about anybody.

EDIT Atheists don't believe in God, beyond that its personal.

Like Theists we all have our personal belief about how the world began and some belief in Evolution.

I personally don't believe in Evolution, that's just me though.

I would guess that a high percentage of atheists accept evolution as fact because most atheists accept reality to be true.

It is never appropriate to assume anyone's position in life. It is far better to talk to them about it.

NO. evolutionism is science. an atheist easily not believe in evoltuion. also, christians can think garden of eden symbolic and be evolutionists.. furthermore... im an evoltuionist and i believe in god.. im a wiccan... i call it intelligent design.. that god set it up that way.. so evolutionism is totally different.

Yes,

Show me an athiest that doesn't beleive in evolution? There is no other 'creation' explanation other than evolution - that requires a belief in God.

Evolution occurs naturally, Creationism requires magic