The activities of the individuals in The Mismeasure of Man match Swales Benchmarks for a Discourse community. The scientific group that the author is talking about had a common set of goals. This group wanted people to see that African Americans were inferior to Whites. They wanted to promote ranking people racially.
This discourse community spread their knowledge through making statements and publishing their experiments.
I think this discourse community set the foundation for the American Jim Crow Laws, because this group kept publishing experiments and statements that dehumanized African Americans. They wanted people to believe that African Americans were racially inferior, and this caused for the Jim Crow Laws to happen. The Jim Crow Laws racially segregated African Americans from Whites.