My first thought for "adapt" was mermaid. I wasn't sure what that had to do with the word "adapt" And then I thought of a woman in a mermaid cut dress wearing flippers, as an adaptation.
Egg... nail.... book... knuckles.... things you can crack!
I had a feeling the word cracked was going to be fun to illustrate.
I originally had a different idea but it never really took off, so I started over listing words that go along with cracked, and the first two words were egg and nail.