We just are evolutionary animals. Evolution seems to be the way God decided to create us. But many evolutionary biologists now think that altruism maybe an evolved trait. There is a social strength to be had in mutual cooperation, that outweighs any individual strength. And there is no reason why the genes that promote this social strength should not be adaptively advantageous..
That is beyond insane. It sounds almost communist/collectivist but on a GLOBAL scale. Even if you apply collectivist mentality, that only extends as far as the tribe/clan/country. I.E. America should conquer all weaker nations, enslave their people, take their oil and resources.
It is also anti-Christian thinking to claim that your flesh makes you naturally good (naturally altruistic, which is insane self-harm for the sake of the hive, without a God, that is just suicidal STUPIDITY). You are claiming the flesh is giving us holy indicators, when the Bible clearly tells us the EXACT opposite, that the flesh TEMPTS you to WRONG actions, to DISOBEDIENCE from God.
And even so, if it is evolution it would NEVER extend beyond the local tribe/clan/country. i.e. it's beneficial for your clan to work together unified, in order to conquer, rape, plunder, and pillage. If you want to claim evolution/flesh as indicators of morality, you need to be in favor of polygamy (reproduction is the #1 priority of evolution), enslaving enemy countries (including taking several wives from your enemies, as humans have done for thousands of years), taking resources of lesser nations to ensure our own prosperity/survival, etc.
Evolutionarily speaking, altruism would never extend to a global scale in a world with limited resources. Both because the species has never even had more than a few years of global knowledge, and because it clearly harms yourself, your tribe, and your country, to embrace a sort of global altruism, instead of the superpower clearly taking the limited resources it needs, enslaving other weaker nations, etc.
If you want an example of tribes that acted in the most clearly evolutionarily beneficial manner, then look to the Vikings, the Mongols under Genghis Khan, etc. Mercilessly kill your enemies, take their women and their resources. That is the best way to ensure reproductive ability (secure several women for every male), increase prosperity, increase the strength of your clan, etc.
It's no coincidence it took Christianity to pacify the Vikings from what their FLESH, their evolution, had turned them into. And now the Scandinavian peoples are among the most peaceful on Earth. Again, because of Christianity.