Biology as defined by humans.

This is the third paragraph of the article:

> “The classic concept says that [a species] is a group of organisms with similar physical and genetic characteristics that can reproduce with each other in nature and produce fertile offspring,” says Xim Cerdá, an ecologist at Doñana Biological Station in Spain who was not involved with the research, to Miguel Ángel Criado at El País. “But it turns out that’s not the case; two species are needed here. We’re going to have to rethink the concept.”

The article doesn't talk about something like "carve nature at its joints"