Primitive tribes in Indonesia severed their fingers to mourn their dead relatives (what is this IQ?

The primitive tribe was called Sukudani, and everyone expressed their condolences in different ways. Sukudani not only wept bitterly, but even cut off a phalanx of his finger to express his grief for his dead relatives. They think that the pain of cutting off fingers can describe the pain of losing loved ones. Cutting off fingers is also an effort by Sukudani to express his hope to prevent catastrophe from happening again.

Why did you cut off your finger? Sukudani believes that fingers are not only in a person or a family, but also have the meaning of harmony, unity and strength. Although in Indonesian, only the thumb has a female finger (ibu jari), they think that five fingers and phalanges are like a family, and they all have different sizes and functions. A harmonious group together can give off real power. As long as one link is lost, it will lose its balance and weaken its strength. The group is very important to them who live in the mountains, so they think that the grief of losing their loved ones can disappear with the pain of cutting off their fingers.

When it comes to IQ, I think they think, feel and understand from different angles, which will definitely be different from what modern people think. After all, the environment is different. But I just want to say that some modern people don't know how to cherish their families. What is their IQ?