Simplify the following text for a Grade 7 native English-speaking person.
Original: Key biologists who contributed work to the synthesis included : Julian Huxley , Theodosius Dobzhansky , Ernst Mayr , Ronald Fisher , J.B.S. Haldane , Sewall Wright , G.G. Simpson , E.B. Ford , Bernhard Rensch and G. Ledyard Stebbins .
Simplified: Julian Huxley invented the term , when he produced his book , Evolution : The Modern Synthesis ( 1942 ) . Other major figures in the modern synthesis include R. A. Fisher , Theodosius Dobzhansky , J. B. S. Haldane , Sewall Wright , E. B. Ford , Ernst Mayr , Bernhard Rensch , Sergei Chetverikov , George Gaylord Simpson , and G. Ledyard Stebbins .