Wesley J. Smith correctly observes that apes don’t have rights, humans have duties.
Joe Carter lists nine things you should know about the scopes monkey trial. Among them,
“The biology book that was used by Scopes was George William Hunter’s Civic Biology. Although a standard biology text, it included the author’s championing of eugenics and white supremacy, his contempt for people with disabilities, and his dislike of charity for the ‘inferior.'” — linked above
In 1925 eugenics was main-stream science, widely promoted by the best minds. Twenty years later it was malicious right-wing nonsense, and nobody had ever believed it.