eli5: Why are babies (including animals)so curious and playful, but lose it over time?


We see it all the time. Curious babies, friendly babies. Puppies, baby primates, elephants. They’re just so curious and interested and carefree.

This can lead to some trouble, which leads me to the question,
Why is it so widespread across mammals?
What has kept young animals to behave this way, but lose it as they grow up? Not to say adults never play or are no fun, but it’s extremely prominent along young ones.

In: Biology

Babies haven’t tried things yet, so they are curious. Adults have been there, done that, don’t need to jump off the wall again because they already know what happens.

It’s a mixture of two main things:

1. The newer you are to life, the more things are unknown to you. Every day brings exciting discoveries, unlike when you’re older and most things you see on the daily, you saw and understood yesterday too.

2. The older you get, the more disappointing things you’ve seen, the more upsetting things you’ve seen, and also you’ve become quite jaded about life. Your sense of self has developed to a degree that you’re self critical. You see things through a judgmental lens instead of a curious one.

For one, them being so lively and running around all the time is vital to develop a child’s musculature.

For another, playing with other individuals of their family/pack/whatever introduces them to social rules.

Last but not least, their curiosity and willingness to learn is critical to the development of their brain. When it comes to language, for instance, children must acquire certain key elements by imitating and learning from their peers before a certain developmental threshold is reached. If this does not happen, this region will remain permanently underdeveloped.

Babies are in constant Theta brain wave states until about 3-4 years old, and every single thing they see hear smell touch experience etc is brand new to them up to a certain age. Also they’ve yet to be damaged by life’s realities yet