The difference is certain religions explicitly teach that you should do harm to certain other people. Darwin never taught that, it's not implied in any of his work, and in fact the Nazis practiced pseudoscience and removed all the Jewish scientists from their positions who would have known about evolution. You know who did teach that? Martin Luther. And the lesson to hate Jews was repeated every Christmas with passion plays, insinuating that Jews killed Jesus. The Quran is also full of violence endorsed for Jews and all who oppose Islam. Christianity was also used as justification for slavery and subjugation of women and gays. These ideologies are certainly harmful and directly responsible for irrational hatreds. To the extent that socialism was practiced as a religion, it did the same thing, preying on religious people as a replacement for what it outlawed. These aren't free people using religion as an excuse, they are subjugated people who require liberation from ideas beyond their control.
It is human biological nature that is directly responsible for all irrational hatreds. Religion is just one very common excuse for them. But anything goes, when the subconscious needs to find those excuses, and again, they don't have to make sense. For close to two decades, Ted Kaczynski sent bombs to random people, he blamed for his personal problems (not getting laid, primarily), and his quasi-religious excuse was ... environmentalism (!).
That is one of the great secrets of human existence: Religion has nothing to do with what people do. Religion only becomes people's excuses for doing, what they would've done anyway. In their respective circumstances. It's the desire that governs the comma sentence, not vice versa. And exactly the same goes for political ideologies and other philosophical stances.
The Muslim world has fallen behind compared to past times, probably since the death of Suleiman the Magnificent in 1566. This current blood is about tensions from recent migrations from Islamic Asia into Christian Europe, muddled together with a certain childish territorial conflict in the Canaan. Christians and Muslims already has this pissing contest going on down through the centuries; when one is doing good, the other goes spitting mad, which is what the crucades were about. Some has pointed to the fact, that it's today 14 centuries since Muhammed instigated people in Arabia (for what ever Moses-type reason), and that one could compare that to the stance of Christian Europe circa 1400 AD; wrapped in religious psychopathy and collective hysteria, witch burnings, persecutions of free thinkers, etc. That could very likely be, what is going on in the Middle East right now, their very own dark ages. One would think, that human hysteria follows a formula. But that observation would also suggest, that Islam has nothing to do with it, just like Christianity had nothing to do with burning women alive for centuries in the name of Jesus the Let-thee-free-of-sin-throw-the-first-rock-at-this-chick Altruist. This'd further support the null hypothesis, that religion has nothing to do with what people do.