Stephen Jay Gould is a voice that is missed in today’s world. Smart, compassionate and analytical but also with a deft capacity to write about complex ideas in an engaging way. In The Mismeasure of Man Gould stepped out of his main field of paleontology and looked at the history of attempts to measure intelligence and the racist assumptions that have run through those attempts. This is the 1981 edition which doesn’t have the chapters on The Bell Curve but still a worthy read.
Is it perfect? No but then a popular account of broad area of research necessarily simplifies and skips over some details. As gateway into understanding the issues there is no better book that I’m aware of.