Original Baby Trap

Here is a modest mystery for you-all. We all know that human babies scream a lot. Meanwhile, the equivalently-young of all other species are super-quiet. Making noise attracts predators! So, if human babies scream, while being MORE physically helpless than any other infant animal on Earth, where is the evolutionary advantage to that?

Well, consider the "play pen". How long have such cages existed? What if....

Just to make this a proper Halfbakery Idea, let's start with a tesseract (see link). That 4-dimensional object can be viewed from various 3D perspectives, one of which features an inner cube and an outer cube. Let us consider both cubes to be "cage-like" in their construction.

The human adults that built the cage now put the world's first (surviving) screaming baby into the inner cage, and hide.

A predator arrives, attracted by the noise. It cannot reach the baby because of the distance between the two cages. But now the adults can surprise-attack and kill the predator, with overwhelming force/numbers. The baby was bait for a trap! For each predator that tries to take the bait and gets killed, that makes the countryside a little bit safer for human hunters. Humans prosper, and the world's first surviving screaming baby gets to grow up and pass on the genes responsible for screaming babies. A million years later, practically all human babies scream.