[azakai]

> sexual selection is natural selection

It's a matter of definition, I think. Darwin made a distinction between natural selection and sexual selection,

> Sexual selection was first proposed by Charles Darwin in The Origin of Species (1859) and developed in The Descent of Man and Selection in Relation to Sex (1871), as he felt that natural selection alone was unable to account for certain types of non-survival adaptations. https://en.wikipedia.org/wiki/Sexual_selection

So the distinction the article here makes is a reasonable one with a long history. But more recently, the terms are often defined as non-distinct,

> Factors that affect reproductive success are also important, including sexual selection (now often included in natural selection) https://en.wikipedia.org/wiki/Natural_selection

[posterboy]

two sides of one coin, init? Edit: I mean, sexual selection is the pinhole of reproductive success, whereas other selective mechanisms are mediated by death, which is quite the opposite.