[RV86]

I read this article on Aeon the other day -- for an ostensibly scientific approach, the author spends a lot of energy anthropomorphizing the biological processes. Plenty of what's said is rigorous and fascinating, but I think that style obscures some of it.

What's really interesting to me is that in many ways this "adversarial" relationship must actually be looked at as a fairly optimal one as far as evolution is concerned -- after all, our species (and plenty of other mammals) have reproduced and thrived across the world.

I'd be very curious to read an analysis of postpartum depression through this lens.

[biomcgary]

Interestingly, the genetic conflict described in the article approaches zero in species with lifetime monogamy because maternal and paternal fitness becomes the same. The genetic conflict increases by the degree of polygamy. edit: I'm an evolutionary biologist, but not a theoretical one, so I might not be aware of edge cases.

[lambdaphage]

Monogamy should decrease sibling-sibling genetic conflict, relative to polygamy, since you can expect to be more closely related to your siblings on average. Even in ideally monogamous species, though, there is still genetic conflict between siblings, and between parents and children. Even though kin selection can drive these relationships toward cooperation, there still exists an opportunity for conflict whenever a behavior would benefit you more than twice what it would cost your sibling. The tension is heightened for parent-offspring relationships, since the expected reproductive potential of the parent is even lower from the offspring's genes' point of view. In the cases where this doesn't hold, such as in _Hymenoptera_ where females share 3/4 of their variation with their sisters through a quirk of genetics, eusociality tends to evolve and you get as conflict-free a family as you could imagine. A hive. That's what the absence of parent-offspring conflict looks like.

Even during fetal development, in which both parties have a strong interest in the survival of the other, there is a range of conditions that would be acceptable (i.e. better than nothing) to both parties. You should still expect replicating gene machines in such a scenario to claw over the surplus: the mother seeking to distribute her resources among all her offspring in a way that maximizes her fitness, and the fetus to maximize its own.

[lambdaphage]

Monogamy should decrease sibling-sibling genetic conflict, relative to polygamy, since you can expect to be more closely realted to your siblings on average. Even in ideally monogamous species, though, there is still genetic conflict between siblings, and between parents and children. Even though kin selection can drive these relationships toward cooperation, there still exists an opportunity for conflict whenever a behavior would benefit you more than twice what it would cost your sibling. The tensioned is heightened for parent-offspring relationships, since the expected reproductive potential of the parent is even lower from the offspring's genes' point of view. In the cases where this doesn't hold, such as in _Hymenoptera_ where workers share 3/4 of their variation with their sisters through a quirk of genetics, eusociality tends to evolve and you get as conflict-free a family as you could imagine. A hive. That's what the absence of parent-offspring conflict looks like.

Even during fetal development, in which both parties have a strong interest in the survival of the other, there is a range of conditions that would be acceptable (i.e. better than nothing) to both parties. You should still expect replicating gene machines in such a scenario to claw over the surplus: the mother seeking to distribute her resources among all her offspring in a way that maximizes her fitness, and the fetus to maximize its own.

[Retric]

The 'Optimal' solution would use less energy. The adversarial relationship seeks a different Nash equilibrium.

[andreasvc]

I think that depends very much on the set of goals that are considered as 'optimal'. which is a matter of definition. I would say that for constraints such as robustness and adaptability to the environment the current situation is likely close to 'optimal'.

[Retric]

"By eight months, the foetus spends an estimated 25 per cent of its daily protein intake on manufacturing these hormonal messages to its mother" That's a lot of energy. Further, human mothers have a high chance of death from natural childbirth compared to most mammals.

Further the energy costs, pain, and suffering from monthy periods has a lot to do with the conflict, wolves for example don't suffer nearly as much.

Realistically it's at best a local optima, but robustness and adaptability are hindered but such inefficiency.

[markburns]

Inefficient on an individual level, but the adaptability and robustness is more on a species level. It's probably pretty efficient in that regard.

A high risk, high reward strategy that works out well for humans that survive and end up with large brains, but terrible for certain individuals for the reasons previously outlined.

[31reasons]

I agree with your point about anthropomorphizing. When you draw stark boundaries between mother and fetus at a biological level the fetus could be termed as adversarial but from holistic point of view the fetus becomes man or a woman and carries human race forward (in time) and also becomes part of immediate family where they create wonderful memories with their parents.

[XorNot]

And all the pretty language in the world doesn't remove the very real dangers to the mother's life during pregnancy which we have only very recently had a decent handle on.

[eevilspock]

Agreed. Lots of stable complex systems are characterized by a "healthy" tension between opposing forces, an equilibrium maintained by negative feedback loops.