make fitness a hybrid_property with a setter
make fitness a hybrid_property with a setter

jcpeterson/Dallinger,jcpeterson/Dallinger,Dallinger/Dallinger,berkeley-cocosci/Wallace,jcpeterson/Dallinger,berkeley-cocosci/Wallace,Dallinger/Dallinger,Dallinger/Dallinger,suchow/Wallace,berkeley-cocosci/Wallace,suchow/Wallace,jcpeterson/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,suchow/Wallace,jcpeterson/Dallinger