Posts Tagged ‘Sexual Selection’


If multiple orgasms were strictly for pleasure, then every woman would have multiple orgasms. It has been greatly speculated that the female multiple orgasm phenomena have no basis in evolution by natural selection. It is claimed to bequeath no advantage to survival. Another problem is the lack of orgasms at all with many women. Neither of these are a serious problem for natural selection.

The easy problem first. If a woman does not have an orgasm, there is still a good chance that she will conceive. As long as the male has an orgasm and ejaculates into her. This should be a no brainer. It leaves a critical question though. Why would any woman ever need to have an orgasm, except for pleasure? So was sex selected for pleasure? I expect that answer to be partially yes, but not completely so. Depending on who you read, female Bonobo’s—smaller chimpanzees—have orgasms too. As an appeasement, often, two female Bonobo’s will stimulate each other into orgasm as a way to make peace. Depending on who you read, human females are the only species who actually have orgasms. I will not contend with why women have them, but it is a good thing!

The harder problem seems to be the question of why multiple orgasms arose in the first place. This has a clear and distinct answer. Males, as it is well known, are forced to stop copulation after having an orgasm, or ejaculating as it is called. Interestingly, I have read an article that implies that some men can also have multiple orgasms. As well, male orgasm and ejaculation, are supposedly, two different things. At any rate, these are rare! The vast majority of men must stop copulating and loose their erections.

What if a woman, after reaching orgasm, had to stop copulating as well? If the male did not ejaculate, then the chances of impregnating her would become very low, but not zero. Some sperm could still leak out. As with everything else in evolution? “May the odds be ever in your favor.” (The Hunger Games) Only men who could ejaculate would produce offspring. Only women who could continue until the male ejaculated would produce offspring. This would mean that selection for stamina in females would become much needed. What better way to produce stamina than to promote the ability to have multiple orgasms?

To balance this, any woman who reached an orgasm too soon and had to stop copulating would leave no descendants and not pass on her traits. She would be what is known as an evolutionary dead end. There might be some women alive today that do have to stop after they reach orgasm, but it is rarely reported in any articles. One thing is for certain, multiple orgasms are selectable for and do convey an advantage. The advantages are more than reproduction, they also include the release of hormones which aid in pair bonding and feeling good. Why would one not select for pleasure if at all possible?

©copyright 2011-2016 all rights reserved

http://shermanbastarache.ca/

Breast Size Selection

on May 16, 2016 in Uncategorized Comments Off

Ph.D. Cavemen? I was just reading a book on sexual selection and breast size was examined. The science is this. Only one third of the actual size of a breast is for milk production or the mammary glands giving the classification of mammals. This is an average sample of mammary size. The other two-thirds of breast size is made up of fat. These are facts.

One speculation was that the fat was selected for so that the fat energy could be converted into milk in times of famine. This theory was debunked by an ugly fact. The breast is the last body part to surrender its store of fat. A female would stop lactating long before the breast fat started to get used. She would also likely die herself first. Fair enough. This fat has no benefit for lactating.

Another theory was speculated on instead. What if larger breast were selected for because they held more milk. Debunked again: they don’t hold more milk. All milk is produced by the one-third portion. It is not stored in the fat. They went on to say that looking like the breast would hold more milk might make fatter breast become a selectable trait. This was refuted by science with the statement that males would not select size without content. They sited an experiment with container shapes and sizes verses volume.

Does this mean that cavemen were Ph.D.’s in physics? They would have looked at breast size, measured the volume of milk in different size breast, compared quantity within sizes, and concluded that larger size had the same production volume as smaller size breasts? I wonder which caveman got the Nobel Prize for this.

The next theory is that just because breast looked more attractive the larger they are, then beauty would win the day. This was refuted by todays standard breast sizes. Most women do not have overly voluptuous breast. The mammary size is just as large as in bigger breast; they just don’t contain as much fat. A long argument was made and nothing was settled in the definitive.

What about treating cavemen as cavemen. They had no way of knowing that larger—fattier— breast did not hold more milk. They were just cavemen after all. Perhaps selection for women with larger breast was a means to ensure that their offspring had more to drink. After all, having more and looking like you have more are two different things. If you thirst and had a choice to drink water from a large cup or a smaller cup, without the means of measuring for quantity, which one would you choose? If the two cups were not transparent and the small cup was full, but the second cup was only half full how could you know this without first drinking?

Selecting for a larger cup size would select for fat storage as an advantage for mating, whether it had any advantage or not. Just as long as it looked like an advantage, desire for that trait would occur.

Every theory must be testable and falsifiable. If actual milk production was a measure, then mammary size could and would have been selected for. Breast would be larger, but without the fat. This did not happen. Fat was selected for. Larger breast looking like they held more milk seems to be the answer that best fits the question.

©copyright 2011-2016 all rights reserved

http://shermanbastarache.ca/

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