Maybe older women had such a high probability of giving birth to babies that had a low probability of surviving that evolution selected for women whose ability to get pregnant cutoff at a certain time.
And older women had a low probability of living long enough to raise their children to an age at which they could fend for themselves.
Or maybe Darwinism isn't tracking true. Today's scientist says, "If reality isn't tracking the model, go with the model that funds you."
He conflates natural selection with evolution. He can't be that smart to start with.