I often use an evolutionary perspective to check how I live my life.
For instance, from an evolutionary perspective, it makes sense to eat mostly less processed food, locally and with the seasons, low on the food chain, and varied foods (mainly vegetables with some fish and meat, and not the same every day). In terms of exercise, it makes sense with variation (walking, running, lifting, swimming), and to vary moderate activity with briefer periods of more explosive and intense activity. It also makes sense to bring it into everyday activities as much as possible. And in terms of child rearing, it makes sense to seek out a community (extended family, if possible) and also to carry the baby on the body and to sleep in the same bed as the baby. All of these things are how humans have done it for millennia and how our evolutionary ancestors have done it for millions of years. If there is a discrepancy between what experts recommend, and what makes sense from an evolutionary perspective, I tend to choose the latter. (For instance, eating butter, eggs, and salt, all of which feel really good for my body in moderate amounts.)
I talked with a friend a couple of weeks ago about her new baby. She sleeps in the same bed as the baby (the baby usually on top of her), and it makes feeding natural and effortless for both of them. The baby stirs gently, she wakes and feeds the baby with just a few adjustments of her body, and they both fall back to sleep. It’s effortless, natural, and minimally disruptive to sleep.
In contrast, if we believe what someone came up with intellectually, we may choose to have the baby sleep separately which means the baby needs to make more sound to wake the mother (be more desperate), the mother needs to get up to feed the baby, the baby needs to be lifted, and it’s all far more disruptive and stressful. It can even be somewhat traumatizing to both of them, and especially to the baby. In an evolutionary perspective, sleeping alone and having to cry loudly to be fed is a signal it is not safe. And when that happens consistently, I imagine it has an impact on the child’s trust and sense of safety, and it’s something they may carry with them through childhood and into adulthood.
I know this is a bit simplistic. For instance, our ancestors’ lives varied over generations and was adapted to geography and climate. And I still find it a very helpful guideline.