Comments on: Natural Gender Selection: Starving Women Seem to Give Birth to More Daughters

By: Heather

Heather — Mon, 16 Apr 2012 01:28:47 +0000

Perhaps a fetus which is of a different sex than the mother’s would not survive as easily because the hormones are not accurately proportioned to correctly strengthen the boy. Perhaps it just makes sense that a female would be able to nourish another female with her own body? Or perhaps the female carrying the male baby can’t keep both alive and thus self preservation kicks in?

By: James

James — Fri, 06 Apr 2012 03:28:46 +0000

Women are smaller, have less muscle, and require less calories.

By: Sunny D

Sunny D — Tue, 03 Apr 2012 15:24:37 +0000

Y’all need to keep in mind the scale of the percent proportion of males. It’s relatively small, and the best we can actually say is that famine can increase the number of daughters, but only by an insignificant amount.

By: Iain

Iain — Sun, 01 Apr 2012 23:54:40 +0000

Well I suspect that in tough times more females are born because they are tougher and they have the babies.
Proposition
We know what the m/f ratio is in a rat breeding.
Put some males and some females on 3/4, 2/3, 1/2, 1/3 and 1/4 necessary food value diet.
Breed the 5 groups with normal diet rats. Also cross combine the fractional food value breeding groups and analyze.
I figure (not calculate) that there would be a few decades of study here. Then when the well is almost dry, breed the second generations together to see if there is a lasting effect.
Hell, with a little good prose this experiment could occupy a full career and have handsome rewards.

By: S. Lenox

S. Lenox — Sun, 01 Apr 2012 22:46:14 +0000

Boys still outnumber girls even in the times of famine, only less so. Is the normal ratio for China markedly different from the normal ratio for the world as a whole? There are all sorts of innuendos unspoken here. It could just be that the normal hanky-panky breaks down somewhat in times of famine. There are questions that have to be asked, that can’t be skirted around, if appropriate sense is to be made of this data.

By: TheCritic

TheCritic — Sun, 01 Apr 2012 17:49:35 +0000

@Miss Celania

That hypothesis does follow a logical path. However, as goes commonly with evolution, it is not the “toughest” that survive. It is the most fit. In times of famine, energy in the form of food is obviously scarce. As science knows, being male requires a higher energy expenditure in terms of development and daily needs by a significant margin. The mechanism that is more likely is that females are more fit to survive in times of famine by virtue of not needing as much energy to survive. If there is a famine and food is split equally. A 210 lbs, 75” male would never survive off 1000 calories a day whereas a 5′ tall, 100 lb female could do so fairly well. I think if it were possible to test the hypothesis, a continued famine that would last long enough to exert evolutionary pressure on the human race as a whole would eventually select for those humans that were smaller in size and weight because they needed less to survive. This would give them better fitness. Whereas toughness is an attribute only selected for when competition winners produce better fitness.

By: Kevin N

Kevin N — Sat, 31 Mar 2012 19:20:59 +0000

I’m with Lyndell. To often, biologists assume a phenomenon must be a result of evolutionary pressures. Much of the time, these phenomena are simply the result of poor design or conditions that were not factors during the evolutionary process. My laptop may behave differently at very high altitudes. But that’s not because the designers planned it that way. They didn’t even consider it.

By: Debra

Debra — Sat, 31 Mar 2012 13:21:55 +0000

In my opinion there is a lot about the female body, menstruation and reproduction that isn’t fully understood. For one I believe that there is a direct link between blood sugar levels and estrogen.

By: Iain

Iain — Fri, 30 Mar 2012 20:59:50 +0000

Perhaps this is a trait shared by all mammals. Seems like it would be a natural selection thing to me because famine is anything but new. It only takes 1 male to fertilize many, many females and should you have many, many males and only one female you are limited to about 1 baby/yr.

By: floodmouse

floodmouse — Fri, 30 Mar 2012 19:16:42 +0000

Quote: “Lab experiments where the male blastocytes of cows survive better in glucose-rich environments identified a possible mechanism.” Translation to vernacular: “Gimme some sugar, baby.” (Mmmm, glucose. Yum.)