Stephen Jay Gould. The Lying Stones of Marrakech (2000)

     Stephen Jay Gould. The Lying Stones of Marrakech (2000) These essays are grouped, the first bunch telling the early history of palaeontology and evolutionary theory. The latter group are a mixed bag. In this collection Gould exhibits a vice that must grow with the awareness that one has made it as an author: he overwrites, rambling on with numerous digressions (and many that aren’t, like the one in this parenthesis), he repeats himself, he builds tangled sentences. In other words, his style gets in the way, which for him is some achievement. Nonetheless, the information is as sound as recourse to original sources can make it, and he does his usual job of debunking common misconceptions and clarifying and deepening common vaguenesses. A book worth reading, despite its flaws.
     He’s especially useful in reminding us that, given a stable environment, organisms will not change - that natural selection can work to stabilise as well as change an organism’s form. *** (2002)
     Update 2020 03 16: Natural slection will also not select against neutral mutations. Hence genetic drift can create subspecies. Also, organisms with insufficient genetic variability are likely to die out if and when habitat changes. That's why rapid habait change will cause extinctions. And because we humans cause rapid habitat change, we also cause extinctions.