May career path took me from the very hard sciences to the biological ones. Though bio is experimentally trivial compared to the complexity of astrophysics, bio theory is millennia harder.

One of my favorite quotes about biology goes something like:

"An alien spaceship lands in your yard. You are kindly invited in to study and tour the ship. The technology is clearly billions of years more advanced than our own. Not decades more, not millennia more, not megayears more, but clearly gigayears more.

This is biology"

Sorry, can't find the exact quote and citation right now!