So a good friend of mine asked me a very interesting question the other day: what would the evolutionary advantage of morning sickness be?
I think that this is a great question because; as he points out, the woman loses food that she has eaten and what could be the possible advantage of losing food value and energy be to a pregnant woman?
My brain works in funny ways :-) and all of a sudden I started thinking about it again and I have two ideas. I have no idea whether either of these is remotely true, they are just hand-waving possibilities in my opinion.
The first is that it’s a genetic sympathy ploy by her genes. Not a conscious effort by her to get sympathy, but a recognition by her tribe’s evolution that she may now need to be a more sympathetic figure – and not be expected to work as hard, not expected to to defend the tribe as much, not expected to play as active a role in the tribes day-to-day activity, etc. – all because she is pregnant.
These are the genes talking, not her conscious desire for better treatment one way or another. It really wouldn’t be susceptible to Game Theory.
The other idea is that it is also a non-verbal signal and the tribe is ” notified” that the woman is pregnant before she is visibly pregnant. And this scenario is more for her value to the tribe. She is now worth more to the tribe because she is in essence (1+a fraction) of a member and thus deserves (1+fraction) more protection from the warriors, (1+fraction) share of the tribe resources, etc.
These situations could also be merged but they probably have separate brain chemistry involved and could be initiated as separate events. They could even be separated on the X and Y chromosomes for further regulation. The overall benefit could be fine-tuned by how strong her reactions are in this scenario (how pysically sick to be and how incapacitated). How strong the tribes reactions would be could also be subject to fine-tuning.
The actual physical presentation of this scenario is also an interesting point. I believe that evolution is not able to decide what the best way of doing something is it just is able to to take an existing biological system and use it for the ultimate goal. And in this case the ultimate goal is just to communicate with the tribe in a manner that is not easily corruptible.
Corruptible in that this scenario would not be dependent on language. It would not depend on particular tribe member(s) trying to verbally convince other tribe member(s) that these actions were nessesary or required. How verbal and intelligent a species is might play a role in some genes “deciding” to find a method that was unconscious. To any witness, someone actually throwing up would be “proof”. I don’t believe that there are many people who could purposefully throw up without any mechanical assistance
See how much time I’ve wasted thinking about morning sickness this morning :-)
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