We humans are very unique though on how much care and dependency babes need. From an evolutionary perspective natur might have just stoped after we gave birth

We humans are very unique though on how much care and dependency babes need. From an evolutionary perspective natur might have just stoped after we gave birth but for humans you need to be still very healthy for much longer. We have a second evolution which we as a species gained due to our more generic and bigger brain and therefore being able to retain and learn more even through generations. Whenever nature stoped we continued (glasses, cancer treatment etc.) I personally would not subscribe to your idea that cancer is our basis and we just let loose. Cancer is just one sickness of a highly complex system. And after all why would longevity even be a goal for evolution? It's a wishful human idea of lifing forever. I myself I'm looking forward to NOT life forever and still today the thought of not being able to end my life for good is my worst nightmare next to loosing my mind.