To compensate for what?? Why in the world would we lose a good self-survival trait (several, in fact, supposedly) if we are evolving?
We started to work together more closely and build tools to facilitate something like hunting for example.
Suppose we had big teeth and claws that were used for hunting previously.
When starting to use tools and cooperation... the better we get at that, the lesser we would need that brute strength (and rather dangerous approach of 1-on-1 combat).
When a trait is no longer needed, there's good chance that it goes away over time.
More then that, LOSING those "brute force" traits actually made us BETTER at making tools etc. Big clunky claws don't allow for precision tool making as well as the finer motoric skills our current hands provide.
Let's take teeth... Take a look at chimp teeth. Those are some sharp weapons, right? Now take a look at the size of their mouths. Now compare that to ours.
Our mouth is a lot smaller. Reason? Our brains have gotten much bigger. As a tradeoff, our mouths had to get smaller. Now, we are at the point where our mouth is even to small for all our teeth!!! Which is why most people need to have their "wisdom teeth" pulled. Mouths like ours also are to small to fit such enormous teeth as those of chimps.
To illustrate with a clearer example of "losing traits as a benefit", take a look at moles. They spend their time living underground in dirty tunnels. It's dark there, so they have no need for eyes. In fact, having eyes down there is a BAD thing. Because they will eventually get infected from all the dirt.
Now, look at moles. They HAVE eyes. But they don't work. They are hidden behind a layer of skin. "eyelids", if you will, that can't be opened anymore.
Evolution is not just the accumulation of abilities and traits. Evolution is also the losing of traits. It's whatever works best for the circumstances at a particular time. Polar bears wouldn't have white fur if they lived in the jungle.
If I had nothing to do with it, why should I be proud of myself?
To put it poetically, I'm "proud" of my bloodline upon realising the following (courtesy Prof Dawkins):
For the past 3.6 billion years, not a single one of my ancestors died before succesfully reproducing.
I find that to be one of the most poetic facts in nature. I think it's very humbling.