People love saying things are “natural” when they want to win an argument.
Meat-eating is natural. Monogamy isn’t natural. Competition is natural. Cooperation is natural. Whatever position you want to defend, somewhere in the animal kingdom you can find an example that supports it.
This should be your first clue that the argument doesn’t work.
But here’s the real problem: natural things aren’t automatically good. Cancer is natural. Dying in childbirth is natural. Most of human civilization is about escaping what’s natural.
We heat our homes when it’s cold. We use antibiotics when we’re sick. We live in groups larger than 150 people and somehow manage not to kill each other most of the time. None of this is natural.
The reverse is also true. Unnatural things aren’t automatically bad. Reading these words on a screen isn’t natural. Neither is surgery or democracy or not dying from a broken leg.
I think people reach for “it’s natural” because it feels like bedrock. Like pointing to something outside human opinion. But what we call natural is still a human choice about which parts of nature to pay attention to.
Bonobos share food and have lots of sex. Chimpanzees fight wars and sometimes eat their neighbors. Both are equally natural. Neither tells us how to live.
The question isn’t whether something is natural. The question is whether it reduces suffering or increases flourishing. Start there instead.