Computers teaching themselves to do something

And so we have come to this.

First, DeepMind managed to get a computer to learn how to walk.
Producing flexible behaviours in simulated environments

Now, it has gotten a computer to learn to play Go from scratch, and gotten so good at it, it beats everyone and everything else in the world.
AlphaGo Zero: Learning from scratch

It begs the question: What is intelligence?
Is intelligence the ability to learn something on one's own? If so, monkeys learning to use a stick as a tool for digging out ants from an anthill would qualify as intelligence, right? A shark learning to hunt for fish is intelligence too, right? But if intelligence is something that equates to being human, then we need to better define intelligence. And then see how it applies to AI.

And the other question: What is life?
Is life defined by the ability to replicate itself? If so, computer viruses, so good at replicating themselves, are alive.

At the end of the day, what does it mean to be human? Will there be a day when computers ponder about the meaning of their existence?