It is actually really engaging and well balanced, I spent a lot of time playing it. However, I'm not sure what is a connection to the theme ;)

I love the idea of evolving enemies. I think it has a lot of potentials. Some general suggestions from my side:

• Sometimes it was difficult to see what tiles the towers could actually reach. Maybe highlighting the actual tile or projecting the radius on them could help.
• It would have been nice to be able to trigger the waves manually to avoid waiting.

It's a good tower defense, the genetic twist is quite nice, even if the theme is not really visible to me.