Posts Tagged ‘evolution of separate sexes’

The Pleistocene Penis

December 17, 2014

Organisms with separate male and female sexes evolved from hermaphroditic ancestors.  Hermaphroditic species are still common.  Many species of plants and some species of animals are able to self-fertilize because they are both male and female.  One would think the evolution of an hermaphroditic organism to a species with separate male and female sexes happened so long ago that it would be impossible for biologists to study.  But, surprisingly, this is not true.  There are over 100 species of plants in the evolutionary process of transitioning between hermaphroditism to a state of separate sexes.  The most familiar species in this transitional state is the wild strawberry, Fragaria virginiana.

Biologists believe the evolution of separate sexes was the result of a beneficial mutation.  Organisms that have separate sexes have increased genetic variation, thus improving the chances the species will survive.  Hermaphrodites suffer higher rates of inbred defects and eventually are eliminated from transitioning populations by the hybrid vigor of male x female combinations.  In stressful environments organisms with separate male and female sexes can allocate resources to seed or pollen, not both–another advantage over the hermaphrodite.

Plants rely on wind and insect pollination.  Males and females of many primitive aquatic animals release sperm and egg in each other’s vicinity, relying on water flow to aid fertilization.  But the evolution of a structure to directly deliver a male’s sperm inside a female’s body was a great advance.  This structure is known as a penis.  The oldest known penis in the fossil record belonged to an extinct species of shrimp (Colymbosathon ecplecticas) that lived 425 million years ago. 

Mammoths and mastodons had the largest penises of any land mammal during the Pleistocene and theirs was comparable in size to those of modern day elephants.

i-2325d7f6567e1a7459f965b85b2d82cd-Elephant-penis.jpg

This bull elephant is in the mood to mate.  Note the large penis.  Mammoths and mastodons had the largest penises of any Pleistocene land mammal.

Homo sapiens has the largest penis of any primate.  There’s no evidence Pleistocene humans ever practiced the bizarre and barbaric practice of genital mutilation known as circumcision.  Circumcisions originated in Egypt about 4400 years ago. Religious fanatics in the ancient Egyptian culture rejected the concept of sexual pleasure.  Circumcision spread throughout the Middle East and Africa and was always popular among religious nuts who thought sexual pleasure was bad.  According to the bible (an unreliable source), the early Jews practiced circumcision, but Moses outlawed the practice.  Joshua brought circumcision back because he wanted his men to focus on smiting gentiles rather than sexual pleasure.  Jews have continued this idiotic tradition ever since.  Circumcision became popular in the United States after the Civil War when once again religious nuts were trying to stop boys from masturbating.   It didn’t work–98% of circumcized males admit to masturbating.  Greedy physicians made up falsehoods, supporting the pro-circumcision crusade, so they could make money on a common but unnecessary procedure.  Even today, most American males suffer genital mutilation shortly after birth, though, thankfully, rates are declining.

About a decade ago, the American Academy of Pediatricians admitted there was no medical reason for male circumcisions.  However, in 2012 religious nuts pressured the AAP to restate their position.  The AAP now states, “the health benefits of circumcision outweigh the risks but the existing scientific evidence is not sufficient to warrant universal circumcision…the final decision should be left to parents to make in context of their religious, ethical, or cultural beliefs.”  So in other words, the AAP is saying it’s ok to torture a baby, if their parent’s religion tells them they are supposed to.  The words cowardly and callous come to mind.

The CDC recently released a report supporting the practice of circumcision because in Africa circumcized men are less likely to spread HIV than uncircumcized men.  Well, first of all, the CDC represents America not Africa.  Second, this reasoning is incredibly illogical.  The spread of HIV could be be completely eliminated if every man had their entire penis cut off, just like broken legs could be prevented with universal leg amputations.  Or less dramatic measures could be taken.  Men could use condoms or engage in sex with less dodgy partners.

There is no medical reason for male circumcision.  There is no significant statistical difference in rates of penile cancer or urinary tract infections between circumcized and uncircumcized men as some have falsely claimed.  There is no moral justication for torturing babies, and I think it is sickening how so many parents are willing to approve of such a stupid, barbaric, religious tradition.  The practice of circumcision, both male and female, should be outlawed.

uncircumcised vs circumcised adult penis

Comparison between a normal penis and the more common (in the U.S.) mutilated penis.

I’m glad I can’t remember my circumcision.  Most American males are strapped down when they are babies and have 12 inches of skin cut off from the most sensitive area of their body…all in the name of religion and tradition.  WHAT AN OUTRAGE!  Are people this insensistive, gullible, and stupid that they would subject their children to torture, just because some stupid rabbi or greedy doctor says they should?

The removal of the foreskin slices off the 5 most sensitive areas of the penis.  Circumcized men are 4.5 times more likely to use erectile dysfunction drugs than uncircumcized men.  These men probably wouldn’t need such medication, if their penises had not been mutilated with the approval of their brainwashed parents.

Reference:

Ashman, T.

“The Evolution of Separate Sexes: A Focus on the Ecological Context”

In chapter 11 of The Ecology and Evolution of Flowers edited by Lawrence Hader and Spencer Barrett

Oxford University Press 2007