The unselfish "selfish gene"

Casual observation of animals seems to suggest that they all hunt, kill, defend and live for themselves but humans seems to be compassionate about each other or at least compassionate to immediate family which is unseen among animals. How is this possible if humans are results of evolution like other species? Shouldn't Humans be selfish like other animals? Human are compassionate and care about other humans so they must be different from other species and hence they must be created by god!!???

Are we betraying our natural instincts when we act selflessly to save our family and friends? Will a person unexposed to religious dogmas ever be compassionate??? Is religion necessary to make human care about each others' welfare??

Richard Dawkins in his famous book the god delusion has given a very compelling explanation for the above questions by explaining how natural selection and human evolution might have made humans compassionate and why religions do not have almost nothing to do with instilling love and brotherhood in us.

Evolutionary explanation for compassion and brotherhood. Humans unlike tigers and lions hunted in packs right from the early days when our ancestors were Chimps. Hunting and gathering food in groups required each memeber of the group to help out the other members of the group so that they could survive bigger enemies and also other tribes of hunters. Those tribes which believed in a common brotherhood and actively helping each other during conflicts will be more capable of winning wars between groups of humans. Humans were dominating most of the other animals due to their ability to make weapons and climb trees so most powerful enemy they had was other humans themselves.

The compassionate tribes and hunting packs of humans would have been more successful in overcoming wars and famine and disease while the selfish tribes perished resulting in a natural selection and procreation of those genes which were compassionate slowly but steadily the compassionate genes were more successful in moving to the next generation.

This argument clearly shows how humans could be compassionate at a group level due to evolutionary reasons without religious teachings although at individual level every one of us still has the selfish gene which would prefer its own survival more than anything else in the world.